Asymptotic behavior of the solution to an equation

Question: Let $c\in(0,1)$  be a constant and let $k$ be a positive odd integer, and let $a(k)$ denote the value of $a$ that satisfies the equation $$(1-a)^kk\sqrt{a}=c$$.  As $k\rightarrow\infty$, what can we say about the asymptotic behavior of $a(k)$?  Obviously, $a(k)$ must approach zero, but at what rate?
Comment: If $k$ is even then there are three positive solutions $a(k)$, and if $k$ is odd there are two.  Are you only interested in the smallest one?
Comment: Good point! I hadn't realized that -- let's assume $k$ is odd and look for the largest solution, in that case.  Question edited accordingly.
Answer: If we divide through by $k$ the equation becomes
$$
(1-a)^k \sqrt{a} = c/k.
$$
If we suppose that $a = o(1/k)$ then $(1-a)^k \sim 1$, so we get $\sqrt{a} \sim c/k$ and thus $a \sim c^2/k^2$.  This is the smaller of the two positive solutions for odd $k$.
To find the larger solution, take logs of both sides of the equation to get
$$
k \log(1-a) + \tfrac{1}{2}\log a = \log c - \log k. \tag{$*$}
$$
Since $a \to 0$ we have $\log(1-a) \approx -a$, so this equation is analogous to something like
$$
-ka + \tfrac{1}{2}\log a \asymp -\log k.
$$
We can find two solutions to this equation by letting one or the other of the terms on the left-hand side balance with the right-hand side; either

$\log a \asymp -2\log k$, which is the solution $a \sim c^2/k^2$ we found earlier, or
$ka \asymp \log k$, which is the larger solution.

Note that in the second case we also have a balance between the two terms on the left, $-ka \asymp \log a$, so we won't get the correct leading order term by just supposing that $ka \sim \log k$.  We need to also consider the contribution from the $\log a$ term.
Let's formalize this to explicitly calculate some terms of the asymptotic for $a$.
If we suppose $a \sim b \log k/k$, where $b$ is some constant to be determined, then
$$
\log(1-a) = -a + O(a^2) = -a + o(1/k)
$$
and
$$
\log a = -\log k + \log\log k + \log b + o(1),
$$
so upon substituting these into $(*)$ we obtain
$$
-ka - \tfrac{1}{2} \log k + \tfrac{1}{2}\log\log k + \tfrac{1}{2}\log b + o(1) = -\log k + \log c
$$
or, rearranging,
$$
a = \frac{\log k}{2k} + \frac{\log\log k}{2k} + \frac{\log(\sqrt{b}/c)}{k} + o\left(\frac{1}{k}\right).
$$
We assumed $a \sim b\log k/k$, so from this we can see that $b = 1/2$, and thus
$$
a = \frac{\log k}{2k} + \frac{\log\log k}{2k} - \frac{\log(c\sqrt{2})}{k} + o\left(\frac{1}{k}\right).
$$
Of course this is pretty non-rigorous, but it should be relatively straightforward to justify the error bounds along the way.


Not able to import data in salesforce from CSV file

Question: I am trying to import data to an app I created in salesforce and not able to import. It is asking me to map salesforce object, but it is not showing salesforce object name which I had created rather it is showing its fields.
Comment: What type of object are you trying to import?
Comment: I have created a custom app where I am trying to import data from csv file.
Comment: Are you using the object which has two master-detail relationship??
Answer: Try dataloader.io, read the documentation carefully or just watch the demo video http://dataloader.io/documentation
this tool is very good and easy for beginners. once you are comfortable and able to understand data management terms then you can move to using workbench.io or dataloader tool for free and unlimited data migration loading tasks.


Relationship between Energy and Time

Question: Is there a relationship between energy and time? What is it?
Comment: I've rolled back the edit here since it completely changed the question. Reviewers, please do not approve edits that completely change a question's meaning.
Comment: This question is *too broad*. One could answer with the time-energy uncertainty relation, with energy conservation through Noether's theorem as jabirali, with the Hamiltonian being the generator of time translations, and surely a host of other, related, but not identical relations.
Answer: Energy is the name physicists give to the Noether Charge that is conserved when a physical system's description through its Lagrangian is unchanged by time shifts. Or, in more everyday language, most physics does not depend on where one puts the $t=0$ time co-ordinate origin. The laws are invariant when we shift our time origin back and forth. Noether's theorem tells us that there is one conserved quantity (in this case energy) for every continuous symmetry (in this case the continuous displacement of the time origin without effect on the Lagrangian) of a system.
Time shift invariance corresponds to conservation of energy.
Likewise invariance with respect to spatial origin shifts implies conservation of momentum: one scalar component for each basis direction of displacement.
Rotational invariance implies conservation of angular momentum.
Answer: The units of energy is $\dfrac{ML^2}{T^2}$ so that way energy is inversely proportional to square of time.  But in most equations of energy, time is never present. Energy is a simpler way to relate work done in complicated systems with variable force. That is found by work-energy theorem. Work is $$\text{force*distance}$$.
There is also Noether's theorem that states that all forms of energy is always conserved as the physical laws governing the universe does not change with time.
Simply energy is not something abstract nor is it a fundamental property of objects. Sure potential energy, kinetic energy exists but we define such quantities to find the work done by a force. Energy is the capacity of a body to do work and nothing more.
Comment: By implication, were time added to the equation we would have a far better understanding of statics and mechanics of physics. If the force is towards the ground but time displacement is horizontal to the force then direction is changed and closed equilibrium becomes variable.
Answer: Here is a model for the relation between energy and momentum, based on classical physics:
A particle at rest receives a linear acceleration. After this acceleration process it is moving, it has kinetic energy which corresponds to a momentum.
For calculating the energy, you consider the length of the path the force of acceleration was applied:
ekin = f x s
For calculating the momentum, you consider the time during which the force of acceleration was applied:
p = f x t
As a result you see that energy and momentum are somewhat symmetric, and energy includes time in the same way that momentum includes space.
Answer: Time is not directly related to energy itself, but it is definitely related to many aspects of energy.
For example, the direction of time (from past to future) can be determined by the flow of energy in the universe. This concept is known as entropy. Our universe is gradually moving from a state of energy concentration (where some regions of our universe contain more energy than other regions) to a state of energy distribution (where all energy in the universe would be equally distributed). The evenness of energy distribution is known as entropy. So our universe is gradually moving from a state of lower entropy to a state of higher entropy.
Gravitation fields have an impact on the speed of time flow. If you replace matter for energy (using E=mc²) it would imply that the speed of time flow would be different for regions of higher energy concentration and regions of lower energy concentration. However, remember that this is a very very vague (some might consider it outright false) interpretation because you are taking energy as mass. While they are definitely interchangeable, their properties aren't the same.

Relationship between Energy and Time


use of unconditional transfer of control instruction

Question: I did not understand why unconditional transfer of control instruction is used in cpu.So if we already know we have to jump to an instruction and skip  some instruction irrespective of any condition then why do we not avoid writing those instruction as they will not be executed and replace them with instruction that will be executed after jump instruction
Answer: To implement if-then-else, when you get to the end of the "then" branch, you need to jump unconditionally past the "else" branch. The breaks in a C switch statement are also unconditional jumps.
You could probably also implement tail recursion by replacing "call" instructions with jumps.
Comment: The range of branch instructions can also be less than that of unconditional jumps, so a conditional distant jump may need to be converted to conditionally branching over an unconditional jump. Hot patching can also use unconditional jumps. (There are also unconditional *indirect* control flow instructions — the target is still dynamically variable as with a conditional branch — but the question is presumably not concerned with those since their utility is more obvious. In ancient times, returns and other indirect jumps were sometimes implemented by self-modifying code changing jump targets.)
Comment: Another oddball potential use for unconditional jump instructions would be with a unified instruction/data cache and PC-relative loads. Data loaded by a PC-relative load might be in what would be the instruction stream to allow instruction fetch to load the data into the (unified) cache, but the data would need to be jumped over.
Answer: As David Richerby's answer notes, the most common use is for implementing if-then-else, where the unconditional jump hops over the else code.
A related use is when the compiler knows conditional code is rarely executed and places it far from the more common executed code, so that an unconditional jump is used to return to the post-conditional code. This is a code transformation from:
<code> branch-on-cond-to-LABEL
 not-"cond"-code
 jump-to-JOIN
LABEL:
 "cond"-code
JOIN:

 branch-on-cond-to-LABEL
 not-"cond"-code

JOIN:

 ...

LABEL:
 "cond"-code
 jump-to-JOIN
</code>
This can enhance memory system performance by exploiting sequential prefetch and avoiding the fetching and storing of a partial cache block of code that is rarely used. (This is an extreme extension of placing the less frequently executed code of an if/else in the later position. This makes the common case a not taken branch which can avoid using a branch target buffer entry, can exploit simple static prediction (forward branches not taken), and can avoid the fetch redirection penalty in some processor implementations.)
It is common for instruction sets to provide a greater range for unconditional jumps than for conditional branches. This means that a conditional jump with a distant target might have to use a conditional jump (with an inverted condition) over an unconditional jump instruction.
An unconditional jump can also be used for hot patching. An unconditional jump to the next instruction (or other nop of the appropriate size) at the start of a block of code (typically a function) can be atomically changed to an unconditional jump to the new code replacing that block.
Another potential use for an unconditional jump instruction is to jump over inlined data. With a shared instruction and data cache, it might be useful to exploit block-granular retrieval from memory and sequential prefetching by placing data with code. This also allows the use of the program counter as a data address register, potentially avoiding the need to load a base address and slightly reducing register pressure.
In some early instruction sets there were no function return (or general indirect jump) instructions, so an unconditional jump instruction at the end of a function was (partially) overwritten to jump to the return address.


Making three membered ring using different reactants

Question:
I am struggling with the above question. It will be the conjugate base of trichloromethane that is involved. The same is true of the carboxylate. However, I have no idea about the reaction mechanisms. Please help.
Answer: I think that both reactions involve carbene as common intermediate which then is the species involved in the subsequent cyclopropanation reaction.
These are the two equations which lead to the formation of the carbene:
$$\ce{KOH + CHCl3 ->  :CCl2 + KCl + H2O}$$
$$\ce{Cl3CCO2Na ->  :CCl2 + NaCl + CO2}$$
Subsequently, the alkene undergoes cyclopropanation by dichlorocarbene.
In the second case, heat is required in order to promote decarboxylation, which is entropically favored.
Answer: You are correct that the first step with both reagents involves the formation of the trichloromethyl anion ($\ce{CCl3^{-}}$).  This anion can eject $\ce{Cl^{-}}$  and irreversibly form dichlorocarbene ($\ce{:CCl2}$).  Carbenes are very reactive intermediates, reactive enough to add to a double bond and form a strained 3-membered ring (a cyclopropane).
The reaction you've shown is said to be stereospecific.  That is, you started with cis-2-butene and wound up with a cis-dimethyl-dichlorocyclopropane; the cis olefin geometry is preserved in your cyclopropane product.  This indicates that the reaction involved singlet dichlorocarbene.  Carbenes can exist as singlets or triplets.  As the following figure indicates, singlet carbenes add stereospecifically (your case), triplets do not.  The "slow spin flip" step in the triplet carbene reaction is slow enough that rotation can occur about what was the olefinic bond and this rotation gives rise to cis and trans cyclopropane isomers.
Answer:
It will be the conjugate base of trichloromethane that is involved.

Only as the initial intermediate! $¸\ce{CHCl3 + OH- ->Cl3C^- + H2O}$
The carbanion will lose chloride and yield dichlorocarbene $\ce{Cl3C- -> Cl- + Cl2C:}$
The latter then adds to the $\ce{C=C}$ double bond.

The same is true of the carboxylate.

No! In this case, decarboxylation (loss of $\ce{CO2}$) is the first step. The fate of the carbanion is however as described above.
Comment: Why does decarboxylation occur? Aren't carboxylate ions stable? Is that why heat is required?
Comment: @RobChem You're right. Usually, they are stable. Decarboxylation may occur when a carboxylate is oxidized to an acetoxy radical, which is not the case here, or when when a resulting carbanion is stabilized by electron-withdrawing substituents. And yes, in your case, heat is necessary for the decarboxylation of the trichloroacetate.


canvas for pixel drawing in GTK3 (gtk-rs)

Question: I just started to use gtk3, and I overwhelmed. I want to draw a pixel rendering (a function graph, drawn in realtime) in a window. I was able to create a window, following some examples, but I can't find information on pixel drawing. I need keywords to google (is it called 'canvas'? Pixel map? Drawing area?), and some advises on how to do it right. Should I keep a separate buffer and do copy every time I need to update window? Or can I just draw into existing gtk object?
Comment: [process-viewer](https://github.com/GuillaumeGomez/process-viewer) uses gtk-rs and draws real time graphs, maybe you can use its code as guideline
Comment: *"Questions asking us to recommend or find a book, tool, software library, tutorial or other off-site resource are off-topic for Stack Overflow as they tend to attract opinionated answers and spam. Instead, describe the problem and what has been done so far to solve it."*
Comment: Process-viewer looks like a very interesting example. I'll dig into it.Thank you.
Answer: For the examples you can generally check the documentation page of the crate itself. There are examples shown in crate documentation.
You can check the documentation of the crate from here.
You can draw your shapes on to the drawing area which is shown as example here on the documentation itself
As far as I have seen, it is pretty much ported with same function and struct names for GTK 3.0.

I need keywords to Google

You can basically google for the GTK library itself and the examples to get the insight about GTK and the easily implement with the help of documentation.
Getting started with GTK 3.0
Comment: Thank you for link. I was their, unfortunately, all examples I found was centered around GUI itself (buttons, widgets), etc. There was no examples of a canvas-style 2D drawing, I start thinking I just don't know how this 'thing' is called at GTK (So, here is my question).


What is the difference between rar and RAR5 compression?

Question: What is the difference between rar and RAR5 compression ?
Which is better for which purpose vs the compression time.
Comment: I'm going to recommend 7zip since both forms of rar are proprietary and any information on the algorithms used for compression will be restrictively licensed to prevent third-party implementation.
Comment: http://en.wikipedia.org/wiki/RAR
Comment: @Wyatt8740 There's an open source extraction utility available from them, though.
Comment: @JopV. Open source, yes. Free software licensed, no. And the license expressly forbids using it to make other RAR compressors.
Answer: When you're choosing a compression type in WinRAR, "RAR" uses v2.9 (sometimes referred to as v4) of the algotrithm, where selecting "RAR5" uses v5. Both are detailed in the wiki article, which others have already linked to.
RAR5 supports some additional encryption features, but you're asking which one is better for compression - from the wiki, it looks like RAR5 might by trivially better for compression speed and smaller in some very specific cases, but the advantages appear to be all on the side of the viewer/decompressor:

Improved damaged archive recovery
Improved file table (meaning quicker browsing of an archive)
Multicore decompression support

In exchange, you're taking the chance that the end user won't have a program that supports the new format, and won't be able to decompress your archive. However, if you're keeping the archive for yourself or you're sending it to somebody that you know has a program that can view it, it looks like RAR5 is the better format.
Comment: In every case where I tried a direct comparison, RAR5 has compressed slightly worse than RAR4 (archives end up ~1% bigger), even with considerably larger dictionaries. I usually compress small numbers of large files (mixed-data CD/DVD images), which might be a factor. Maybe some of those new features eat up more space than the better compression saves, in that scenario.
Comment: v4 has a 32MB dictionary whereas v5 can have a dictionary up to 1GB which makes it useful for doing backups.
Comment: @RushFrisby Actually, with v2.9/v4 the dictionary size setting doesn't go above 4MB for me.
Comment: @JopV. v4 max is 4MB, you're right. 32MB is the default for v5 and can go up to 1GB.
Comment: @user202729 Thank, I updated the link.
Comment: @SqlRyan: It seems like the UI has been changed. Now `RAR` assumes `v.5` by default, and where it used to be `RAR5` is now `RAR4`. I got recently [confused over it](https://superuser.com/questions/1370137/why-is-winrar-5-not-giving-me-an-option-to-use-rar5-format-and-only-rar4) already.
Answer: There isn't a difference.
RAR is the overal compression schema.
RAR5 is the revision of the compression schema

RAR is a proprietary archive file format that supports data
compression, error recovery and file spanning. It was developed by a
Russian software engineer, Eugene Roshal (the name RAR stands for
Roshal Archive) and the RAR software is licensed by win.rar GmbH.
v5.0 - supported by WinRAR 5.0 and later. Changes in this version:

Maximum compression dictionary size increased to 1 GiB (default for WinRAR 5.x is 32 MiB and 4 MiB for WinRAR 4.x).
Maximum path length for files in RAR and ZIP archives is increased up to 2048 characters.
Support for Unicode file names stored in UTF-8 format.
Faster compression and decompression.
Multicore decompression support.
Greatly improves recovery.
Optional AES encryption increased from 128-bit to 256-bit.
Optional 256-bit BLAKE2 file hash instead of a default 32-bit CRC32 file checksum.
Optional duplicate file detection.
Optional NTFS hard and symbolic links.
Optional Quick Open Record. Rar4 archives had to be parsed before opening as file names were spread throughout the archive, slowing
operation particularly with slower devices such as optical drives, and
reducing the integrity of damaged archives. Rar5 can optionally create
a "quick open record", a special archive block at the end of the file
that contains the names of files included, allowing archives to be
opened faster.
Removes specialized text, multimedia, and Itanium executables compression algorithms; consequently some files of these types
compress better with WinRAR 4.x (Rar4) than WinRAR 5.x (Rar5).

RAR (file format)
Comment: Thanks for the quick response .. Saw the wiki earlier but was not sure about the terminology


Does buoyancy change on smaller scales?

Question: For baseball size objects on the order of centimeters across we have experience with what floats and what doesn't. A stick will float and a rock will not. But what if the rock were a grain of sand? What if it were a thousand times smaller still? Would it's small size allow it to float because of surface tension?
Answer: You're confusing buoyancy with surface tension. The former applies to (macroscopic) objects which are (at least partly) immersed, while the latter applies to inter-fluid surfaces.
Thus, a sufficiently small grain of rock (sand) may stay on the water surface owing to its tension, but will sink if submerged (say by a breaking wave). If you make it very small, however, it will undergo Brownian motion (when submerged) and the fluid model (which describes buoyancy) is no longer applicable.

In answer to the comment: if submerged, it's (by definition) underneath the surface: surface tension is out of the equation and buoyancy rules. In addition, there is of course a frictional drag force between fluid and object (which depends on the size, shape, and speed of the object, as well as the viscosity and density of the fluid). After some initial transient period, the drag force, gravity, and buoyancy become balanced and the object sinks at a constant rate, which does depend on the object's mass, size, and shape.
Comment: Won't the rate at which it sinks be different if it sinks at all. Assuming it isn't heavy enough to break the surface tension underneath it even when submerged.
Comment: @Alex velocity is a different question and I suspect there is a terminal velocity in water question on this site.
Comment: It's not just velocity, theoretically a grain of sand loses potential energy as it breaks the bonds between water molecules. It would be interesting to know what height you can drop it from without sinking and so on. I would like someone to discuss these forces and how they behave at smaller scales.
Comment: @Alex And now that is a third question.  This answers the stated question.
Comment: Terminal velocity does increase with size.  Mass is r cubed and area is r squared.
Comment: @Frisbee  Only true if you maintain the topological shape. compare a 10-kg flat plate with a 10-g sphere.
Comment: @CarlWitthoft No kidding.  Mass is r cubed and area r squared is the same topological shape - a sphere.
Comment: @Frisbee quite right. the terminal velocity depends on mass, size, and shape of the object (and the density and viscosity of the fluid ...) -- correct my last sentence.

Does buoyancy change on smaller scales?


Hard drive and power consumption of current Time Capsule

Question: What kind of hard drive is build into the current Time Capsule? Is it a SSD? Also, how energy efficient is the current Time Capsule, how much energy does it consume? I can't find this info on Apples product pages.
Answer: Since it's a 2TB or 3TB storage you can be sure it's HDD, since the price is 'only' 299$ or 399$. There are for the moment no (commercial) 2TB SSD drives or maybe one or two which are really really expensive. On the product page is also stated that the Time capsule is ussing a Hard drive, otherwise there would be stated Soild State drive or similar.
The enviromental report, including energy usage can be found here: https://www.apple.com/environment/reports/docs/AirPortTimeCapsule_PER_feb2014.pdf
Answer: When in use, apple states it uses 11watts at 115 volts. The power supply is 88 percent efficient according to apple. These figures refer to the now current (december 2014) version of time capsule and apply to both the 2gb and 3gb model


How to completely remove Ubuntu?

Question: I installed Ubuntu using Wubi installer, but I couldnt boot to it. So I uninstalled it on the Control Panel. Then I tried the full installation wherein it boots to the Ubuntu environment. After installing Ubuntu there, I couldnt boot to my Windows 7 anymore! So in an attempt to salvage the whole thing, I inserted the Ubuntu CD again and chose Erase Ubuntu and Reinstall. (I was wondering, why wasn't there an option to just "Erase Ubuntu"?) I did that though, and I got my Windows 7 back. But upon checking my drives via the "Create your own partition scheme" (not sure if it's the exact words) I saw that one of my partitions still has Ubuntu on it, and there's no way I can delete it if I don't overwrite another Ubuntu! I can't access that partition on windows 7 either! Need help!
Comment: post the output of bootinfoscript http://bootinfoscript.sourceforge.net/
Answer: I think your problem is only about the partition. Linux use ext2/3 file system and Windows doesn't support that file system, so normally you cannot see the drive which format in ext2/3 on Windows. My suggestion here is you can use PartitionMagic (or any tool works with partition), erase that drive and merge it to another fat32/ntfs drive, so you can retrieve it completely
Comment: No need of 3rd party tool. You can delete the drive and extend other partition using disk management utility. run "diskmgmt.msc" in windows run  prompt (press Win + R)
Comment: If you are still getting the menu giving you an option of what to boot you are probably using some of the contents of that Ubuntu partition to get that menu to work. Here are some instructions: http://askubuntu.com/a/143482/63886. In particular you need to replace the MBR which will allow you to boot directly into Windows. After that you can use Windows tools to delete the Ubuntu partition and maybe merge the space back into a Windows partition.

How to completely remove Ubuntu?


translate rss-feed that was grabbed by cURL

Question: my most trusted programmers and thank for all the help!
I grab rss-feed by jquery-ajax using php curl. It's loading very nicely directly on the page. However, I would like to translate the text, that is now html, title within h2 and text within p, wrapped by a div-container.
Google's api-script for translation doesn't seem to run after the content was put into the div. Really nothing happens. I tried both putting the script in the ajax-url-file and the file that the content is displayed on.
I used .live(), but no result.
Any idea?
Thanks!
--
In one of the methods I create a table i mysql and put in title, link and text. After that I echo the table.

$query3 = mysql_query("SELECT * FROM temp_rss_$id") or die("$error_msg");
while ($row3 = mysql_fetch_array($query3)) {
    $title = htmlentities($row3['title']);
    $text = htmlentities($row3['text']);
    $link = $row3['link'];
echo "

        $titel

        $text
";
}

The title is within in a h2 and an anchor, and the text is within a p.
Using simple jquery, this method without ajax, to grab this:

$('a.rss-links').live('click', function() {
    $('#media').load(php_file);
});

Works like a charm. Then there's the google-api-script:
function initialize() {
    var text = document.getElementById('media').innerHTML;
    google.language.detect(text, function(result) {
        if (!result.error && result.language) {
            google.language.translate(text, result.language, "en", function(result) {
                var translated = document.getElementById("media");
                if (result.translation) {
                    translated.innerHTML = result.translation;
                }
            });
        }
    });
}
google.setOnLoadCallback(initialize);

It doesn't load the google-script. What can be done? Of course it does work if I put the text directly on the page, without loading another file. Using ajax and append(result) instead of .load doesn't make a difference. Any idea?
Thanks!
Comment: what is your attempt? post some code you have attempted.
Answer: You can call that function after the .load() runs, as it's callback, like this:
$('a.rss-links').live('click', function() {
    $('#media').load(php_file, initialize);
});

This will call the initialize function once the .load() has completed and the new content in the #media element is there and ready to translate.


Completely remove Adobe Suite

Question: I need to totally remove all traces of Adobe from my laptop running OSX 10.6, and then reinstall it. I'm having serious problems with Adobe apps, specifically InDesign and Illustrator. Any tips (or list of steps) would be very helpful.
Comment: Be warned, you need to deactivate the software first, so you can re-activate after the install
Answer: First remove the standard way through Add/Remove programs then run one of the following:
Removal Tool for CS3 Products
Removal Tool for CS4 Products
These are not standard "removal tools" but they are meant to help when you want to reinstall a product from scratch when there are errors such as you said and they have helped me in similar situations.
Comment: +1 because this is exactly what I have done many-a-time.
Comment: Macs don't have Add/Remove Programs. ;-) However Adobe does provide an uninstaller at `/Applications/Utilities/Adobe Installers/Add or Remove `. The clean tool is however what Josh K is looking for.
Comment: Running the removal tool shows no "sessions" able to be removed. I uninstalled (again), if that helps any.
Comment: Yep, still not working. I uninstalled, then reinstalled. No dice.
Answer: Some of this may be repetitive but follow these steps and you should have absolutely positively NO trace of Adobe left on your computer.

Remove all Adobe fonts from /System/Library/Fonts, /Library/Fonts/, ~/Library/Fonts
Remove all these additional fonts from the same folders:
WarnockPro-Bold.otf
WarnockPro-LightDisp.otf
WarnockPro-BoldCapt.otf
WarnockPro-LightIt.otf
WarnockPro-BoldDisp.otf
WarnockPro-LightItCapt.otf
WarnockPro-BoldIt.otf
WarnockPro-LightItDisp.otf
WarnockPro-BoldItCapt.otf
WarnockPro-LightItSubh.otf
WarnockPro-BoldItDisp.otf
WarnockPro-LightSubh.otf
WarnockPro-BoldItSubh.otf
WarnockPro-Regular.otf
WarnockPro-BoldSubh.otf
WarnockPro-Semibold.otf
WarnockPro-Capt.otf
WarnockPro-SemiboldCapt.otf
WarnockPro-Disp.otf
WarnockPro-SemiboldDisp.otf
WarnockPro-It.otf
WarnockPro-SemiboldIt.otf
WarnockPro-ItCapt.otf
WarnockPro-SemiboldItCapt.otf
WarnockPro-ItDisp.otf
WarnockPro-SemiboldItDisp.otf
WarnockPro-ItSubh.otf
WarnockPro-SemiboldItSubh.otf
WarnockPro-Light.otf
WarnockPro-SemiboldSubh.otf
WarnockPro-LightCapt.otf
WarnockPro-Subh.otf
Search for and remove any files labeled 'Adobe' or 'Macromedia in all of these folders

$find . -name "*adobe*" -print

    /Applications                       /System/Library/
    ~/Applications                      ~/Documents/
    /Applications/Utilities             ~/Library/
    ~/Applications/Utilities

Remove these explicit folders

    ~/Documents/Updater/
    ~/Library/Acrobat User Data/
    ~/Library/Application Support/Adobe
    ~/Library/Applications/Macromedia
    ~/Library/Application Support/Macromedia
    ~/Library/Application Support/Adobe PDF
    ~/Library/Caches/Acrobat
    ~/Library/Caches/Adobe
    ~/Library/Caches/Opera Cache
    ~/Library/Preferences/Acrobat
    ~/Library/Preferences/Adobe
    ~/Library/Preferences/Adobe
    ~/Library/Preferences/com.adobe
    ~/Library/Preferences/com.adobe
    ~/Library/Preferences/com.macromedia
    ~/Library/Preferences/Dreamweaver
    ~/Library/Preferences/Opera Preferences
    ~/Library/PreferencePanes/AdobeVersionCue
    ~/Library/receipts/com.adobe
    ~/Library/StartupItems/AdobeVersionCue

Search for and delete the following files and/or folders:

    ACE2CACHE
    Acrobat
    Acrobat Webcapture Cookies
    Adobe
    Adobe GoLive 7.0 Prefs
    Adobe Illustrator CS Settings
    Adobe InDesign
    Adobe Photoshop 8.0 Paths
    Adobe Photoshop CS Settings
    Adobe UM
    Com.Adobe.Acrobat.Pro6.0.plist
    Com.Adobe.Acrobat.Pro7.0.plist
    Adobe Registration Database
    Adobe Installer.tmp

Open terminal

sudo rm -rf ~/.Trash/*

Restart
Answer: These are great tips, all organized in one place and are probably sufficient. Of course you will want to backup your system as well as clone it prior to doing this surgery.
dcc's list neglects a few files and folders, for example /Library/Application Support in favor of ~/Library/Application Support, (i.e., suggesting only the user (~)/LibraryApplication folder) and there a few others along these lines. Check the root/Library... equivalents of the User folders as there is a lot of stuff in there.
Digging deeper into/private/var/db/receipts/ there are a bunch of adobe bom and plist files that can go..
In /private/var/db/bootcaches/ there are some incomprehensibly named folders several of which contain adobe ".playlist" files that can go.
In Library/Logs/Adobe/Installers/ there are a bunch of log files. Remove these but reserve them for further spelunking.
in /Library/LaunchDaemons/ and /Library/LaunchAgents/ there are Adobe files to be chucked.
In /Library/Internet Plug-Ins and Library/Internet Plugins (disabled) there may be Adobe files.
In Library/Frameworks/ there is Adobe Air stuff and sometimes more. Plonk 'em all.
In /private/tmp/ there may be AdobeApplicationManager. bye bye...
In /System/Library/ColorSync/Profiles/ you may find ColorSync profiles from Adobe apps. Obviously keep AbodeRGB1998.icc and others that are used universally and not used by Adobe.
If you have other User accounts then you may find a file .Adobe at /Users/[useraccountname]/ The dot in front means this file is hidden. Also, there may be another set of ~Library... and other ~/... folders and files as there was with your own user folder.
Adobe files and folders often appear in the Users/Shared/ folder.
More:
~/Library/Receipts/
~/Library/Preferences/ByHost/
As for the log files, adobe may install files that do not have the name adobe in the filename. This way you have no way to tell they are from Adobe. Using the Log files you can find some of these (if any). Also, the log files give you the times of installations. If you, for example, search on an installation date and time for your entire machine you may find files installed within a few seconds or minutes of known Adobe files. Tag these and research them. Usually you can delete them. They often have to do with DRM or anti piracy efforts. This is another recommendation that when installing an app, don't be doing other tasks while the installer is running.
Finally, there are some files labeled with only the name of the Adobe app. They might have "Bridge" or "Photoshop" in them. These can usually go.
It is possible to use a free app called EasyFind to find all of the files listed by dcc and myself in this post. Highly recommended.
To search on date and time you will want to search on (usually) Creation Date or sometimes Date Added. Spotlight has the capability of doing this. However, frankly, it misses or ignores areas of the system that seem  obvious. So I use the paid HoudaSpot which, though it is just a Spotlight front end, does visit all of the system. I have a suspicion there is a way to do this in the Terminal or another freeware app that can do this but have never bothered to look.
Answer: What errors/problems are you getting?
Have you deleted Adobe files/directories in/Library/Application Support/Adobe  which is different than Users/Yourshortlogin/Library/Application Support/Adobe?
Comment: Yes. The errors I'm getting are an Error Code 3 with InDesign when I try to export, and a complete failure to start Illustrator.

Completely remove Adobe Suite


Losing concentration

Question: During some kind of repetitive task which doesn't involve thinking, I lost my concentration and forgot what I was doing. When I told someone about this I said 途中でぼけてしまった but I wonder if that is the best way to describe such an occurrence. 途中で集中しなくなった sounds quite odd to me somehow. 集中を失った would be a translation of "lose concentration" in English but I'm not sure that is good Japanese. Is 途中で間を抜けた or something like that too strange?
Answer: I think

途中でボケてしまった

is a valid way to relate the fact that you lost your concentration, but I guess it is rather colloquial.
You could also say

気が逸れてしまいました

which could mean that something else caught your attention, but I guess this "something" could just be another thought, in which case it would just mean that your attention drifted.
If you want to use 集中, then I think

集中ができなくなった

is better.
Finally, 集中を失った seems to exist, but it sounds more like a medical condition and I don't think it quite fits the situation here.
Answer: I think

途中で間を抜けた

is bit too awkward to describe "losing concentration" since it sounds like you've left the place in the middle of talking. A similar expression :

途中で間が入った

can be used when your activity was paused while you are staying in the same place.
When you feel losing concentration while doing tasks you are getting used to such as routine chore, I would feel

ボーっとしてきた。: Absent-mindedness.
集中力が途切れてきた : Concentration has started to lose.
気が抜けてきた : Losing motivation.

Losing concentration


How much citric acid should I use to preserve mayonnaise on a cups/ml ratio?

Question: I was thinking of making mayo for sandwiches to get me through the winter and was wondering if I could make fairly large batches that would keep for a long period of time with the aid food grade citric acid. Here's the problem I have never done this before with any sauces besides tomato sauce were you dissolve about 1 Tbsp citric acid per quart of tomato sauce, so I"m assuming since I'm making a preservative based liquid I should dissolve 1 Tbsp per quart of boiling water?
Answer: First, don't make assumptions based on other recipes. Food safety is so complicated, not even the specialists try to predict anything. They test recipes empirically until they have found ones that work. Of course they take guesses at what is likely to work, but they only know after they've made and measured it.
Luckily, people have tested recipes for longer life mayonnaise. The result is that you have to use 1 gram of acid and 15 g of water per yolk. You also have to pasteurize the yolks, which means that you need to get them above 65 Celsius during the mayonnaise making stage. The curdling temperature of yolks is changed by the acidity and the speed of heating, with this ratio, it occurs somewhere between 82 and 88 Celsius. So you really have to be very accurate when producing the longer-shelf-life mayonnaise, using both a thermometer and a high-sensitivity scale (don't measure by volume!). I suggest reading the whole document on safe mayonnaise making here, it is quite informative.
Your idea for "large batches to get me through the winter" probably still won't work, though. First, I wouldn't keep this mayonnaise indefinitely long. It only gives you a 5D reduction for salmonella, and of course you still get bacterial contamination of other species after the mayo is made. They may be slow to grow with all the acid and in the fridge temperature, but they still grow. Also you have mold and plain old quality problems such as rancidity and lactic fermentation. The authors of that article only confirmed the safety for 4 weeks.
Second, you can't be scaling the recipe indefinitely to make one large batch. As you saw above, you need a very tight temperature control. If you were to dump a dozen of yolks into the bowl, and then add 12 cups of oil, no burner will be able to maintain constant temperature throughout the emulsion, especially once you have enough air in it that conduction slows down. 3 yolks are normal for a batch, up to 5 can be done well, above that it becomes quite difficult.
Third, you might find out that you simply don't like it. This mayonnaise should have a pH of 3.5 or below. This is not yet pickle-taste territory, but it's still very sour. If you don't enjoy mayonnaise which tastes of citric acid foremost, you might find out that you don't want to do acid preservation.
Comment: I know eggs are routinely coated with mineral oil to extend shelf life and retard evaporation of the contents. I have heard of sailors coating eggs with petroleum jelly so eggs would last up to a year on ocean voyages. It would seem that eggs are the critical ingredient. Perhaps preserving the fresh eggs is another way to skin this cat? Raw eggs will last 5 weeks if kept at 40 degrees F. http://www.foodsafety.gov/keep/charts/eggstorage.html P.S. Commercially produced eggs have a "hidden" Julian date on the carton that tells you when they were actually packed.


What is the meaning of Schon Rosmarin

Question: What is the meaning of Schon Rosmarin?
Comment: No context, no meaning.
Comment: Hello Carole, this forum is meant to provide answers to questions regarding German language in terms of grammar, rule, style, etc., not for translation services. Questions should demonstrate some effort on the side of the person asking. And of course, as others already pointed out, meaning is always depending on context, so you have to show the broader context of your quote. - You can rephrase your question, and it will be answered.
Answer: I can only guess that you mean Schön Rosmarin and not Schon Rosmarin. Schön Rosmarin is the title of a composition by Fritz Kreisler, a 20 century musician from Vienna. As this is a song title, it makes barely sense to translate it, but literally Schön Rosmarin means something like Lovely Rosemary, while Rosemary refers to the spice, not to the female name.
Comment: Nice example of how omitting the dots changes the meaning.

What is the meaning of Schon Rosmarin


How to bound the dimension of infinite dimensional Hilbert space?

Question: Lets say I have a density matrix $\rho$ encoded into a physical system. Lets say I can have access to as many copy of $\rho$ as I want. I perform hmodyne detection on the copies in phase and out of phase and based on the measurement result always lies in a circle nemely
$$P^2+X^2\leq r$$ where $P$ and $X$ are real values and correspond to measurement results out of phase and in phase respectively. Based on this measurment results what can I say about the dim of hilbert space corresponding to $\rho$? Is it possible to bound the dimention?
Answer: Basically, the average value of $P^2+X^2$ is the average value of the energy, hence of $4n+2$ (with the suitable normalization). Therefore, what you describe is known ans an energy test in the literature.
Basically, if your state is essentially restricted to a superposition of the Fock states of $O$ to $d-1$ photons, we cans say that it is restricted into a subspace of dimension $d$.
The details of the energy test vary, and there is still ongoing research work to find the most efficient one. One recent example is in  PRL 118 200501 / arXiv:1701.03393, by Anthony Leverrier which does not assume a product state and use heterodyne detection. Basically, if your state has a non-negligible support of Fock states of $d$ photons or more, it will have a non-negligible probability to have a value of $P^2+X^2$ to be higher than $r$ and to be detected by the energy test.
One way to compute this probability would be to use the explicit expression of the Fock states using Hilbert polynomials, but I don't know a nice and simple expression from the top of my head.
Comment: For two or more modes, things work essentially the same way, but with a worse scaling (exponential in the number of modes)
Comment: About the de Finnetti approach: as in all verification problem, we can never guarantee the we weren't especially unlucky. All we can do is gurantee that a "bad" state has a low probability to pass our test. In our case, it would be something like a state with a support higher than $η$ out a given subspace of dimension $d$ has a probability lower than $ε=f(r, η, N)$ to pass the test. In De Finetti test, this is ensured by symmetrizing the state (or perform a symmetric test) such that the optimal way to cheat is to send a symmetric state anyway. But we can never have $ε<1/N$
Comment: Thanks for your answer! I am a little confused about this quantum de finneti approach. Each time that we make a measurement the quantum state collapse and basically we lose some information about the quantum state. How can we justify that by performing some measurement the fidelity between resultant state and the original state is reasonably high? For instance, look at this paper:  arXiv:0809.2243. Basically the idea of the paper is to perform measurements on some part of the system and bound the dim of Hilbert space but how can we justify the collapse of quantum density operator?
Comment: And what if we have two modes? how things work in that case?


How to get more quests from Vex after bypassing a bug with Heimskr's house?

Question: I was given the Shill job quest to place a gem in Heimskr's house in Whiterun.  The problem is that if you have already completed the Stormcloak Rebellion questline, Heimskr's house is gone - it is covered by rubble and does not appear on the map.  The Wiki makes note of this and suggests using the console to advance through the quest, IF you are playing on a PC.  I am, but while this can "finish" the quest, Vex will not offer you any more jobs when you return to her - the option simply isn't in her dialog.  Any suggestions?
Comment: possible duplicate of [Where is Heimskr's House?](http://gaming.stackexchange.com/questions/44464/where-is-heimskrs-house)
Comment: @Rory: Well, kind of, but this builds off of this, talking about a problem that arises after listening to the answer in the other question.
Answer: I've had the same problem before.
Where is Heimskr's House?
I believe the only solution is to go back to Vex and decline the quest.  Then she'll give you something else.  Either that, or re-load to a point before you got the quest and hope that she doesn't give it to you again.  As far as I'm aware, you can freely reject these quests and ask for a new one until you get one that suits your needs.
See also:
UESP - Skyrim:  Thieves Guild (Faction) - Improving the Thieves Guild
UESP - Skyrim:  Heimskr
UESP - Skyrim:  The Burglary Job - Bugs
Answer: I had a similar issue and used it as an excuse to learn more about how Skyrim is put together.
The issue has to do with the fact that the Thieves guild radiant questline is a complicated mixture of quests (eg: TGRSL) depending on other quests (eg: TGRShell) and all kinds of inconsistent weirdness between them such that, if you use console commands, you can cause the whole thing to be in an invalid state. It does seem like it would be possible to fix this problem, but I doubt Bethesda's priority is to make console commands safer. Fortunately, you can correct the invalid state in TGRShell.
Long story short, these are the console commands (~) you can use to fix it (fixed it for me at least). TGRSL is the quest ID for Vex's heist job. This is what I advanced. If this isn't what you advanced, replace the "TGRSL" in the first command with the quest ID you advanced:
SetPapyrusQuestVar TGRShell pTGRSLRun 0
SetPapyrusQuestVar TGRShell pTGRVexRunning 0

You can verify that these variables were changed with this command
ShowQuestVars TGRShell

(Use PGUP/PGDOWN to scroll).
Now Vex should offer quests again. I hope this helps someone.
Comment: This should be marked as the correct answer -- I found this question when searching for a solution to this exact problem and those commands fixed it. Thanks!
Answer: Install the Unofficial Skyrim Patch (original / Legendary Edition - PC) / (Special Edition - PC) / (PS4) / (Xbox One). Its related fix (v1.1 - 2012-08-03):

Thieves Guild radiant jobs will no longer select Heimskr's house as a target due to it being destroyed during the Battle of Whiterun.


Map Reduce query in erlang

Question: I'm trying to write a mapreduce query in erlang for riak but I'm having trouble getting my head around it.  Does anyone know where I can find an example of an erlang mapreduce query, or can write one, that will perform the SQL equivalent of a count operation? It would also be helpful if someone could explain what the actual query does line-by-line too. I've managed to write one in js but erlang is pretty different.  Thank you.
Answer: Riak comes with a set of predefined mapreduce functions implemented in Erlang that you can use as a guide if you are trying to write your own functions. One of the functions provided is
reduce_count_inputs, which counts inputs (as long as the input are not integers) and might be useful for your scenario.
I have also created a library of map phase functions implemented in Erlang that you can look at.
Although I believe it is possible to pass in Erlang functions as part of the mapreduce job specification in a similar way to how you send anonymous JavaScript function, it is usually not recommended, and I have not done this myself.
Comment: Thank you for the information. Reduce_count_inputs doesn't quite do what I require but it's a good start.
Answer: I always look into riak sources to find some good examples.
Here module which implement standard mapreduce funs: riak_kv_mapreduce
This is a simples one, which just returns value of the object.

Map Reduce query in erlang


Airdrop Mechanism

Question: I'm trying to find information about native token Airdrops. What is the mechanism?
For example, the user send 5 ADA to the wallet of the project and the smart contract will send you back (2.5 x Amount of ADA) of $NATIVETOKENS.
Is there a simple mechanism for this or it needs a smart contract?
How are distributed for example the Meld Tokens? Or the WMT?
Answer: I was also searching for this info, but I was not able to find the answer how this is done. Same mechanism is used for an example for the Spacecoins or the newest one Hosky. I do not think you need smart contract for this but I am not sure.
I think this is simply done by the bash script running on some server with synced wallet. You can basically monitor your wallet, once you will receive the ADA you can filter the wallet ID using cli and construct outgoing transaction. And that's it.
Answer: Yes that's basically a vending machine script.  There are some scripts available in github
Comment: Can you please give some examples and post a few links? Short answers get flagged as the low-quality posts.

Airdrop Mechanism


SQLite + EntityFramework pair leaves the connection alive after disposing of the context

Question: I'm using SQLite for .Net and EntityFramework from .Net Framework 4.0. Everything was ok until I moved from SQLite v.22.214.171.124 to v.184.108.40.206. From that time code like this
using (var context = new EntityContent(sqliteConnectionString))
{
    context.ExecuteStoreCommand(mySqlScriptString);
    /*
     * or do some stuff with context entities and call context.SaveChanges()
     */
}
deleteSQLiteDbFile(getDbFilePath(sqliteConnectionString)); // <-- here is the error

throws the error System.IO.IOException: "The process cannot access the file 'mydatabase.dat' because it is being used by another process."
It's all because of moving to the new sqlite3_close_v2() API in SQLite v.220.127.116.11 (see this). As you can see in this ticket you should properly dispose all sqlite commands and readers. But EF 4 doesn't do it (at least in the .net framework 4 version). For instance, see ObjectContent.ExecuteStoreCommand method. It implicitly creates a command from SQLite connection and doesn't dispose it.
Yes, I can write my own executeStoreCommand(ObjectContent context, string script, params object[] parameters) method with proper command disposing but what to do with context.SaveChanges()?
Does anybody know if it fixed in next releases of EF or SQLite? Or may be there are any workarounds?
Answer: The reason for this problem is a changed close behavior in the System.Data.SQLite which is somehow not compatible with EF anymore.
Details see here: http://www.mail-archive.com/sqlite-users%40sqlite.org/msg74770.html
Since this was only in my integration tests I used the workaround from here to solve that:
System.Data.SQLite Close() not releasing database file


Make sharp dashed line path stroke on rounded corners in Photoshop?

Question: Following this answer, I've tried to make rounded corners with dashed stroke, but the output is blurry. Is there any method to make a sharp dashed stroke in Photoshop?
Comment: @pnj4: I think there is a language barrier here. If you upload your image to a public location on the web, I will be happy to add a link in your question. @e100: I think "summary" means "result" in this context. @DA01: The question is tagged with `adobe-photoshop`, unless you put it there.
Comment: @pnj4 - Do you have access to Adobe Illustrator?  It's not a pure-Photoshop solution, but it would save you much time to create a stroked path in illustrator and copy it into Photoshop.
Comment: using what tools?
Comment: I'm not clear what "The summary is blurry" means.
Comment: Philip you understood right i guess he is saying about output @pnj4 please rollback if i am wrong...
Comment: @DA01: Adobe Photoshop CS4
Comment: @e100: it means the result & I've uploaded to [here](http://d.pr/yVu0)

@Philip Reagan: Yes uploaded to [here](http://d.pr/yVu0)

@Farray: I have Illustrator too but I have very little knowledge in Illustrator :D

@all: sorry for VERY LATE reply ;)
Comment: Post you own answer how you did it and accept it as right answer let everyone know how you achieved this....
Answer: Since you have access to Illustrator, the easiest way to do a dashed stroke is to create the stroked shape in Illustrator and copy/paste it into Photoshop.
Since you're unfamiliar with AI, here's a quick step-by-step:

Use the Rectangle Tool (M) to create your shape:

With your shape selected, Effect ⇒ Stylize ⇒ Round Corners...

With your shape still selected, Open your Stroke palette and set the Dashed Line attributes to your liking.

You now have a shape with a dashed stroke.  Copy it and paste into Photoshop.  If Photoshop asks how you want to paste, choose "as pixels".

Note on above:  Illustrator's display will likely anti-alias your shape.  If you screengrab and then paste into Photoshop, you will still have "blurry" problems.  If you copy and paste the object itself, you will not have this issue.  You should also keep your shape dimensions in whole-pixel increments to avoid Photoshop anti-aliasing when it pastes the pixels.
Comment: he already mentioned his answer farry....
Answer: Pulling in a vector from illustrator is the best way to go like Farray said. Sometimes I will take a screen shot of my object selected and paste and cut it out with the selection. Unfortunately it is rasterized and not customizable.
Comment: Welcome to GD! For future reference, your answer would probably work better as comment (once you have more reputation to post comments)
Answer: Dear Pnj4 its just an assumption not a real answer just to give you a little help,

kindly attach a screenshot or anything
  to get  proper answer

As you already created your rounded corner with dash line stroke, where ever i know your stretching or by mistake made it wrong that's why its getting blurry, try to recreate your steps carefully might be you'll get your real output without any blur and all. i am listing some tutorial for you i doubt you made mistake  with brush presets.

Dotted Line Border this will help you i am sure.
How to dash line
3 Easy method to create dotted lines


Database design for a school system

Question: This system has to manage students, teachers, staff and grading. This is for production and is not a school assignment. As such, please let me know if I can improve on any aspect. :)
My main concern is automation. I'd like my software to be able to run regardless if I still exist.
I'm using SQLite as the database:
create table User
(
ID integer primary key autoincrement,
Username string,
Password string
);

create table Area
(
ID integer primary key autoincrement,
Name string
);

create table Subject
(
ID integer primary key autoincrement,
Name string,
Abbreviation string,
IDArea integer references Area(ID)
);

create table Level
(
ID integer primary key autoincrement,
Name string,
Principle string
);

create table Grade
(
ID integer primary key autoincrement,
Name string,
IDLevel integer references Level(ID),
Observation string
);

create table StaffType
(
ID integer primary key autoincrement,
Name string
);

create table Staff
(
ID integer primary key autoincrement,
IDStaffType integer references StaffType(ID),
Name string,
LastNameFather string,
LastNameMother string,
DateOfBirth string,
PlaceOfBirth string,
Sex string,
Carnet string,
Telephone string,
MobilePhone string,
Address string,
FatherName string,
MotherName string,
FatherContact string,
MotherContact string,
FatherPlaceOfWork string,
MotherPlaceOfWork string,
DateOfHiring string,
YearsOfService string,
Formation string,
Specialty string,
Category string,
Salary string
);

create table GradeParalelo
(
ID integer primary key autoincrement,
IDGrade integer references Grade(ID),
IDStaff integer references Staff(ID),
Name string
);

create table Student
(
ID integer primary key autoincrement,
IDGradeParalelo integer references GradeParalelo(ID),
Rude string,
Name string,
LastNameFather string,
LastNameMother string,
DateOfBirth string,
PlaceOfBirth string,
Sex string,
Carnet string,
Telephone string,
MobilePhone string,
Address string,
FatherName string,
MotherName string,
FatherMobilePhone string,
MotherMobilePhone string,
FatherProfession string,
MotherProfession string,
FatherPlaceOfWork string,
MotherPlaceOfWork string,
Observations string
);

create table Attendance
(
ID integer primary key autoincrement,
IDStudent integer references Student(ID),
Attended string,
Date string
);

create table SubjectGrade
(
ID integer primary key autoincrement,
IDGrade integer references Grade(ID),
IDSubject integer references Subject(ID)
);

create table ScoreRecord
(
ID integer primary key autoincrement,
IDSubject integer references Subject(ID),
IDStudent integer references Student(ID),
FirstTrimester integer,
SecondTrimester integer,
ThirdTrimester integer,
FinalGrade integer,
Year string
);

Any glaring room for improvement?
Comment: I don't have time for a full review right now, but a quick note besides those I've seen below: I feel "Observation" as seen in various tables may benefit from being stored in a separate table for each (ie: StudentObservations) with timestamps and perhaps user auditing. In general I would think User roles (for who/what they can and can't change) would be pretty important for a school too, though this sounds like a pretty small setup.
Comment: I would suggest to set all columns which should not contain NULL values to "non null".
Comment: Are you sure sqlite is what you want to use?  What do you expect the number of concurrent users to be (reading & writing)?  What are expected # of rows in each table?  How will you handle audit trail, delete/undelete, edit/undo?  Don't store passwords as plain text.  Any idea up front what kinds of reports you'll be running?  It's pretty clear for staff & students you will need to adjust the fields from time to time; it may be worth it to come up with a general mechanism for extensibility there.
Comment: Concurrent users: 2. Each table will have at MAXIMUM 5 million rows, and that's REALLY stretching it.
Answer: One thing which immediately jumped out to me is this:
LastNameFather string,
LastNameMother string,
FatherName string,
MotherName string,
FatherContact string,
MotherContact string,
FatherPlaceOfWork string,
MotherPlaceOfWork string,

Your design assumes that every student will have exactly 1 mother and exactly 1 father. I can tell you now that will not be the case. Students with divorced parents may have two mothers and two fathers, all of whom will want to have their contact info listed. Some students may have gay or lesbian parents, and thus two fathers or two mothers. Some students may have neither, and instead may have a legal guardian who is neither their father nor mother.
One solution to this would be to have a table for a "person", and link people to each student. Identify whether that person is a father or mother (or non-parental guardian). This will also simplify having siblings: you can have the same mother, father, etc. for multiple students.
For the majority of students, this won't be an issue, but for more than you might think, it will. Do those families and your management a favor by making it easy to handle various family scenarios!
Comment: I'll keep that in mind for the next iteration. I'll create a table "Guardian", with IDStudent, IDGuardianType(parent, guardian, etc.) and Name, Contact Info, etc.
Comment: Do keep in mind the possibility that a child will have two mothers or two fathers on their birth certificate.
Comment: Be aware that not everyone fits the neat firstname+lastname pattern that's proposed, too.  That *might* be adequate for the students, but their parents are less likely to all come from the local culture.
Answer: Some things that jumped out
take martin york's suggestion and be consistent as much as possible, user identifying primary key names like user_id as opposed to id for every table as it will make it less confusing for those writing/maintaining the SQL. For foreign keys, I would suggest table first e.g. area_id as opposed to IdArea as it flows better with natural language.

Looking at your ERD, there are places where it is failing to get to 3NF (which is a level of database normalization you should strive for when possible)
Use proper field types, looks like you are using string a lot, things like date of hire should be actual timestamp/datetime column, gender can be enum, etc.
All the contact/phone information in the staff and student tables can be places in more appropriate phone/contact tables as those are one to many relationships.
Your attendance table...looks like it either states that a student attended school a particular day or not...seems like this would be something more on the per class level, as a student could attend a half day and such.
Is it possible for a staff member to have more than one staff type, if so you should have an associative table to link staff to staff types
Instead of years of service in staff, could you not just use the date of hire column to figure that out instead of every year updating the year of service column.

Those are some things I noticed, hope it helps.
Answer: Comments

All your ID (unique ID's) are called ID (this is OK and it works for you)
But I have found when you start doing joins this may become hard to read. Thus I like to name the unique key after the table. eg User_ID on the User Table etc.
To make the Identifiers easier to read either use camel case or separate words with _
Identifiers like IDArea run together a bit much. So IdArea or ID_Area or Id_Area (Remember pick a style and be consistent though).
The Staff table has a lot of information in it a lot of which could be NULL.
I would rather have a Person table to hold people information. Then a relationship table to hold relations ships between people. This way when your DB is expanded (and in a Business environment this will happen) you can express other relationships between staff.
Related to Staff. Like Staff I would keep the personal details of Student in the Person table. Note. I would still keep a seprate table (or view) for Staff/Student that has a link into the Person table.
Comment: Regarding point #1, I use Entity Framework, so in my code I go: .FindAllStudents().Where(s=>s.ID == parameterID); Like that. :P
Comment: Point #1 is a swings and roundabouts thing. If you always call your primary key ID then you know that ID is always your primary key - there's convention over configuration benefits that arise as a consequence to offset the potential SQL issues (though I'd suggest that tableID = table.ID is fairly clear)
Comment: @Murph: This is a code review all points are subjective. And on simple queries then ID is fine. But once you start writing complex multiple nested queries (which is what happens in the real world) that extend past 2 three pages the extra clarity does actually bye you some benefit.
Comment: everything is a compromise, you give up one thing to gain another. And I've *done* complex queries (-:
Answer: I agree with all of the other's observations above, but I will touch on a few particular points:

You could definitely do some additional normalization. There are places where this may come down to a conscious decision NOT to fully normalize (there can be some reasons not to . . . Depending on your problem space), but overall, when I begin to see the same field names appearing in multiple tables (other than PK/FK relationships), I become suspicious. An example (which Martin York touches on, but I will take a step further) is all of the "People" fields. Note the level of duplication between the "Staff" table and the "Student" table with regard to Mothers/Fathers/Workplaces/Professions. Mothers and fathers are people. Staff are also people. Students are people.
I notice you have an "Observations" field in your student table. I strongly recommend you define an "Observations" table with a foreign key to the "Students" table with the following fields (The Staff_ID is to record who made the observation). Over time, observations will accumulate, and it will be helpful to know when, and who made them:

Observations Table: Observation_ID, Student_ID, Observation_Date, Observation, Staff_ID

I agree with the notion that there should be a separate "Contact_Info" table. Further, I am betting you will want to send the student (or the student's parents) mail from time-to-time. I would include an "Addresses" table for this purpose. I won't pretend to know how it works in Bolivia, but in the United States, schools like to mail out report cards (although, parents ALSO can track their student's progress over the internet these days ...).
Staff salaries can change. While you may decide it is acceptable to overwrite this value, this is another area where correct normalization indicates a Staff-Salaries table, which includes fields for ID, Salary, and Effective_Date.

How far you take the normalization process can be tricky, but as one or more of the other commenters observed, you should always shoot for 3NF. I promise you, from my own painful experience, that when your boss decides he wants a report showing staff salary increases over a five-year period, you will be glad you did.
While it often happens that there is a conscious, design-based decision to "de-normalize" a table, the decision should documented for those who may need to maintain your database in the future, when you are no longer there.
Hope that helps!
Answer: I appreciate that all the names you choose for tables and fields are understandable and self-explanatory. Only "GradeParalelo" does not make sense to me.
Nevertheless, I would suggest adding short comments to describe fields and tables. Include the motivation for design decisions that required complex thinking, especially if you expect the system to be maintained by different people.
Comment: It's because it's in Spanglish :P Basically, here in Bolivia you can have many 'instances' of a grade. And a student belongs to a single instance of a grade.
Answer: There seems to be duplication, I'm just going to put changes for each table in a separate answer.
Staff Table

The mother and father contact information could be put into a separate table. That way you are not limited if someone has different contacts
contact_id, contact_name, relationship, contact_number, contact_address, fk=staff_id

Can a Staff have more than one StaffType? Like can a teacher be a coach? If so the table must be altered. Will all types have a specialty?
Regarding DateOfHiring and YearsOfService, the length of service can be deduced using the current date and the DateOfHiring.
I don't see a way to deactivate a staff member. What happens when they are terminated? Dropping their record is not a good solution. You may want to consider adding a termination date to the table.
Answer: All tables use automatically assigned sequences as keys, this is not proper data modelling. Many people do that and forget about the actual/business/real world Primary Keys. You don't want to allow multiple users/areas/subjects with the same name, thus you must add Unique Constraints on User.username, Area.name, Subject.name, Subject.Abbreviation, etc.
The ID in SubjectGrade is useless, it's never used/referenced, the logical key is IDGrade,IDSubject.
Similar for ScoreRecord: IDSubject, IDStudent instead of ID

Database design for a school system


Upgrade to Lubuntu 17.04 from Ubuntu 16.04

Question: Is it possible to upgrade from Ubuntu to Lubuntu without losing everything? (Files, Accounts, Data, Document, etc.)
Comment: Your question is unclear. Are you asking how to reinstall? Or how to achieved the desired change using only the package manager? A backup is wise in either case, so the 'without losing everything' seems moot.
Comment: I doubt that it's possible. The upgrade process will examine your existing system files and upgrade you to the same flavor and not to another. Also, you may have to go from 16.04 > 16.10 > 17.04 and not straight from 16.04 to 17.04. If you really want Lubuntu 17.04, back up your data and do a clean install including over-writing your existing home folder.
Answer: backups are worthwhile - so always backup first.
yep; but still better to backup should anything go wrong.
another alternative is to add LXDE to your existing ubuntu system; eg. my "ubuntu 16.04" system also has lubuntu-desktoppackage installed; so I can at login have unity (standard ubuntu), xfce (xubuntu), lxde (lubuntu), mate (ubuntu-mate).
note: loading many desktops is not intended. loading many desktops like I do can cause them to misbehave, or your system have more quirks than a pure system, but it's an option.  they will all be 16.04; so if its the later 17.04 you want; you'll need to re-install (remembering backups first are a good safety measure!!)


Chart for Fame/Infamy for Fallout New Vegas?

Question: When first gaining a level of Fame and Infamy in Fallout New Vegas the game gave you a chart of what every title meant. I accidentally quickly exited out of this and I can't find its image anywhere online and any wiki I came across wasn't helpful. I was wondering if anybody could provide an image of the chart of levels of Fame/Infamy or make one themselves so I know how much each faction either loves me or hates me.
Answer: You can find such a chart on Nukapedia, which is an excellent reference to check before asking a question about Fallout on Arqade.
Here's a screenshot:
Comment: @Bucky That's right. Idolized is the best.
Comment: Thank you for the help! Just wanting to confirm to make sure I have it right, "Vilified" is the worst Infamy status you can have, right?


Blender2.8 freezes when using smooth brush

Question: lastly I can't work properly, after few strokes with smooth brush blender just stops working for like 5-8s, it happens very often.

My specs:
System Windows10 64bit
16GB RAM
processor Intel core i7-8750H 2.20GHz
Graphic card GTX 1070

I usually work on like 1milion faces without dyntopo.
My pc can handle these models in edit mode, but smoothing in sculting mode is lagging, please I need help

Already tried:
Reinstalling Blender 2.8 to newest version,
Decimating my model to at least half polygons count,
Also for some reasons I can't open my model in 2.79 version, even without UI loaded.
Comment: You obviously can't open a Blender 2.80 Beta scene in Blender 2.79, because Blender 2.80 uses a different file format. Select your object, export it to .obj, then import that .obj into Blender 2.79
Answer: I have the same issue but in multires. Using airbrush stroke method instead of space increased performance.


From Edge to Poloniex

Question: Bought bitcoin and have a balance in a exchange account at Poloniex. Is there another step I need to take or is this where the estimated value that changes is where I will be able to send this back to Edge, and change back to USD.
I guess my question is: Is this money at work for me here or do I need to do something else.
And is this deposit safe where it is or is there a layer of security that needs to be taken.
Obvious to say I'm new to this and also thank you for your help!!
Comment: @arubi: I guess Edge refers to a bitcoin wallet app formerly known as Airbitz.
Comment: Hi Don, it's not really clear what you're asking here.  Maybe explain exactly what it is you're trying to do, and also explain what is Edge.
Answer:
Is this money at work for me here or do I need to do something else.

I believe Poloniex is a currency exchange. If you want to earn money simply by trading currencies back and forth, I believe you need to be an active manager of your trades.
Poloniex seem to offer margin trading - In general I suspect this is a good way to lose money if you are new to finance.
If you don't know whether your money is at work for you then it almost certainly is not.

is this deposit safe where it is

Storing money on an exchange when you are not actively trading is one of the least safe places to hold money.
The safest would be an offline wallet with well backed up keys and/or recovery seed phrase in multiple locations, with rehearsed recovery and with instructions to your heirs in case of bus.

From Edge to Poloniex


Only execute specific shortcodes

Question: For my wordpress content editor I need to specify the shortcodes I want to get executed. Is there a chance to define an array of shotcodes which get executed and all other shortcodes in the content which are not in the allowed array are getting ignored?
Answer: It's easier to remove specific shortcodes than it is to remove_all_shortcodes() and enable specific shortcodes.
To disable specific shortcodes from display everywhere, you would use the following:
<?php
add_filter( 'the_content', 'oxo_remove_shortcodes', 0 );

function oxo_remove_shortcodes( $content ) {

    /* Add the shortcodes that you would like to remove to the array below. */
    $shortcode_tags = array(
        'shortcode_1',
        'shortcode_2',
        'shortcode_3'
    );

    /* Remove each of the shortcodes listed above. */
    foreach ( $shortcode_tags as $shortcode_tag )
        remove_shortcode( $shortcode_tag );

    /* Return the post content without the shortcodes listed above. */
    return $content;
}

ALTERNATIVE
Depending on why you only want to enable a few shortcodes, you may be able to get away with creating a filter that checks if the content has_shortcode() from an array, and then strip_shortcodes() from the content, if it does not.
NOTE: a filter like that would be server intensive, and time consuming in terms of site performance.
Comment: Hey Courtney, thanks a lot! The problem i have is that i dont want to delete them instead they should show of as plain text unexecuted. My editor saves generated html so its necessary that specific shortcodes aren't executed. They will later get executed on the front end. I don't know why there isn't any balacklist or something like that.
Comment: Do you know the names of the shortcodes that you want to exclude?

Only execute specific shortcodes


SharePoint 2010 Windows Authentication User Interface

Question: The company I work for currently services 13 School districts who all authenticate through different active directories to our SharePoint 2010 site. We are currently looking for a way to switch the user interface for logging in. I was wondering if there is anyway of changing the Windows Authentication dialog box, to look like a form, without using forms or claims based authentication. We are also trying to avoid using mixed authentication.
So I was wondering, is there any way to change the look and feel of how users log in without switching the authentication type from windows authentication.
Answer: No, the only way to do this is via Forms Authentication using Active Directory as the authentication source.


Is there any reason to switch to Visual Studio 2010 for Windows Forms development?

Question: I can't find any new features or improvements for Windows Forms in Visual Studio 2010. Am I missing something? I guess there are new features to C# and other parts of .NET in general. Any reason specifically to the GUI development portion?
Answer: I thought PEX was being added. I think it's valuable:
Pex Tutorial
Answer: Although it's not specific to GUI development IntelliTrace is reason enough for me to go to 2010: http://msdn.microsoft.com/en-us/library/dd264915(VS.100).aspx
If you have in-house users that test alpha or beta level versions of your application IntelliTrace is a great way to get more detail about what was happening during failures/unexpected situations.
Answer: Probably not any REAL must haves to require an upgrade, but lots of little things that may make your lives easier.
In .net 4.0 (thus used in VS 2010), the charting controls are built in, as opposed to having to install them manually.  Not a ture reason to upgrade, but will make it easier if you use the charting controls.  ScottGu's Post
In addition, other benefits to VS 2010 (not specific to WinForms, but will be beneficial) are Searching and Navigating improvements, Code Intellisense Improvements, Add Reference Improvements


Are both RVR and visibility minimum required for CAT I ILS?

Question: Is it required to have both RVR and visibility to be more than minimum for ILS CAT 1 or one of them is acceptable. If both required which one has priority.
Answer: If RVR (which is both runway-specific and more precise) is available, then it is controlling. If not then visibility (single value for the airfield) is controlling.
For example, typical Cat I minimums might be 1800 RVR or 1/2 Statute Mile (when the runway has an ALSF-II approach lighting system). If the RVR is near 1800 for one runway, the visibility may be low enough at the sensor for the airport that the prevailing visibility is reported as 1/4 SM -- too low to allow you to fly the approach (Part 121 rules, at least). But with the RVR, since it's measured at your runway (and often, right next to the touchdown zone of your runway), you're legal to fly the approach, since that much visibility "right here" means you have an excellent chance of seeing the approach lights at your DA.
Also, for all ILS approaches below Cat I mins (Special Cat I, Cat II, Cat III), only RVR matters.  The difference between each of those mins (1600 for Special Cat I, 1200 for Cat II, 600 for Cat III) are too fine to be captured by a "prevailing visibility" sensor.


How to get continuously frame data from Camera2 API for streaming purpose?

Question: We are working on real time video streaming using Lib streaming library. Lib streaming library supports old Camera api, all is working fine but we required to integrate Camera2 api to Lib streaming library. Some of functionality like video preview display using Camera2 api, we integrated but we need to get video frame data for stream continuously, how to get it? please suggest the way forward.
In Lib streaming library, they used below callback method for frame data:
<code>mCamera.setPreviewCallback(new Camera.PreviewCallback() {
        @Override
        public void onPreviewFrame(byte[] data, Camera camera) {
            // here we get frame by frame data
        }
    });
</code>
Comment: have you got a solution to this question?
Answer: I didn't completely get your question, but you can achieve this using setRepeatingRequest of camera2 API. It has a captureRequest parameter in which you can add an output surface where you want to get the frame data.


Relation between Entropy and Temperature

Question: I have read the Entropy is defined by:
S = Q/T
which means that Entropy is indirectly proportional to temperature. Still we say that Entropy increases as temperature increases.
For example, if the temperature of a crystal is increased from 0K to 115K, we would instinctively say that entropy is increasing because kinetic energy of the particles is increasing which is leading to more randomness.
Both things contradict.
What am I missing here?
Comment: S is not defined as Q/T.  And dS is not even defined as dQ/T.  The change in entropy $\Delta S$ between an initial- and a final thermodynamic state of a system can be determined by calculating the integral of dQ/T for a reversible path between the initial final states.
Answer:
I have read the Entropy is defined by:  S = Q/T

Entropy is not defined by that equation. A differential change in entropy is defined by
$$dS=\frac{\delta Q_{rev}}{T}\tag{1}$$
Where $\delta Q_{rev}$ is a reversible transfer of heat.  Then
$$\Delta S_{1-2}=\int_1^2\frac{\delta Q_{rev}}{T}\tag{2}$$

which means that Entropy is indirectly proportional to temperature.

Your conclusion that absolute entropy is inversely proportional to temperature rise is incorrect because $Q$ is a variable. To determine the entropy change you need to evaluate equation (2) for a reversible path between the initial and final equilibrium temperatures.

Still we say that Entropy increases as temperature increases.

Not necessarily.
Case in point is the reversible adiabatic (isentropic) compression of an ideal gas in which the temperature of the gas increases. Since the process is both adiabatic and reversible $\delta Q_{rev}=0$ and thus it follows from equations (1) and (2) the change in entropy is zero.
At the microscopic level, the increase in temperature results in greater molecular disorder and an increase in entropy. But the lower volume provides fewer ways to distribute the molecules (energy) reducing disorder and entropy. The result is a net change in entropy of the gas of zero.
Hope this helps.
Comment: The differential change of entropy is $\frac{\delta Q_{rev}}{T}$. There is no $dT$ at the denominator. A practical formula, in the case of an isochoric ($V=constant$) process, could be $\frac{C_V}{T}dT$, where $C_V$ is the constant volume heat capacity.
Comment: @GiorgioP Pure carelessness. Thanks GiorgioP
Answer: The formula has $2$ variables, because heat is not a constant.
Heat is a flow of energy, and we must understand the change of entropy as a result of that flow. Normally the temperature increases when there is an heat input in a mass of material, So, energy and temperature are related. But they don't tell the whole history.
It is necessary $334 kJ$ to melt $1kg$ of water at $273 K$, but the temperature doesn't change in the process. So, the mass has more energy and the same temperature when liquid, compared to solid. And there is a change of entropy: $$\Delta S = \frac{\Delta Q}{T} = \frac{334}{273} = 1.22 kJ/K$$
In order to boil $1kg$ of water at $373 K$, it is necessary $2265 kJ$. Now the change of entropy is:$$\Delta S = \frac{2265}{373} = 6.07 kJ/K$$
So, the denominator increased, but the numerator increased much more.
When the temperature increases along the heat input, the entropy also increases, but the example of a process without change of temperature is more clear in my opinion.


How to illuminate the edges of an object in the bge

Question:
First of all, I don't know if this is what I should call that effect. I'd like to illuminate an object's edges once the object is detected by a ray sensor in the game engine. For example, I'd like the edges to turn red when the ray sensor hits an enemy. Ive been looking up tutorials, but I haven't found anything. Please help.
Answer: There is no build-in option that provides you an outline effect.
But there are other options. E.g. via GLSL shaders.
Additionally you can create an similar outline by

duplicating the mesh,
scaling it up a little,
assigning it green shadeless color

(This will not result in a one pixel outline.)


Set autocapitalizationType globally for all uitextfield

Question: I would like to set autocapitalizationType for all UITextFields in my application globally. Can I do this by overriding a method in a category for UITextField?
Answer: No, categories extend the functionality of a class.
You could subclass UITextField, set the value you want, and use your subclass everywhere you want that behavior,


Transfer of thermal energy always refers to heat?

Question: So there was one MCQ in our exam which made me delve into this. Does the transfer of thermal energy always refer to heat transfer? If we have resistance wires thrown inside a system and current passes through them , would that be considered as transfer of thermal energy by work? Because work is eventually transferred to the system as thermal energy dissipated in the wires.
Comment: Is light considered heat?  Radiant heat transfer begs this question.
Comment: There is no heat transfer when the wires get hot.  The electrical energy is converted to internal energy of the wires.  However, once the wires get hot, the heat can be transferred from the wires to the rest of the system; this definitely does count as heat transfer.
Comment: @DavidWhite "begs the question" = "raises the question"? Blackbody light radiation and impingement can be pretty safely considered heat transfer, although geometrical considerations can become complex. Laser light? It gets complicated. A laser, for example, is not at thermal equilibrium.
Comment: @ChesterMiller what if we have an adiabatic system in which wires are considered a part of system, then shouldn't this be a work transfer as Philip Wood pointed out.
Comment: Yes.  That is correct.  As in any application of the 1st law, it depends on what you identify as your "system."
Answer: We need to get terminology straight. First, in thermodynamics, we normally refrain from using the term "thermal energy". If you look at the classic textbook Heat and Thermodynamics by Mark Zemansky, you won't find the term "thermal energy" used. It is too often confused with temperature, heat, and the non-kinetic energy component (i.e., potential energy) of internal energy. Thermal energy is not transferred. Only heat and work. In thermodynamics, the term "heat" refers to energy transfer due solely to temperature difference. The other form of energy transfer, work, is essentially due to force operating through distance (it could be mechanical forces, or in this case, due to the force the electric field exerts on the electrons in the wire).
When current passes through the resistance of a wire it raises the wire temperature due to work done by the electrical field. The transfer of energy from the now elevated temperature wire to the lower temperature surrounding materials or air is then in the form of heat. So, in effect, the transfer of energy from the electrical energy source (say battery) to the surroundings of the wire, involves both heat and work.
As to David's comment, radiant heat transfer is energy transfer by electromagnetic waves. It still requires a temperature difference. I don't believe light itself is considered "heat". Photons are not "heat". However a source of like (i.e. incandescent bulb) can cause heat transfer, due to its temperature. The heat transfer can be a combination ofconduction, convection, and radiation. The radiation component involves electromagnetic waves and needs no medium. The other modes require contact with solids or fluids.
Answer: Thermal energy is not, I think, a defined term in Thermodynamics. If the wires through which the current passes are considered part of the system, then the VIt is a work input to the system, but it's important to note that the work is done irreversibly and its effects are the same as those of a quantity VIt of heat entering the system! If the wires are not considered part of the system, then we have a straightforward transfer of heat into the system from the wires.


Autofocus with canon EOS 1200d

Question: Can my EOS 1200d autofocus with1.4x canon teleconverter and canon 300 mm f4 lens. What will be my maximum aperture using both of these.
Comment: Did you read the specifications of the 1.4x canon teleconverter? What do they say? What exactly in those specifications is missing in order to answer your question?
Comment: Welcome to the site. Please use our search functionality before asking new questions. Also, it is highly advised to use your manual for basic questions.
Answer: According to Canon's website, the 1.4x Extender III is compatible with EF 300mm f/4L IS USM and

*When Extender EF 1.4x III is attached, the lens maximum aperture will be reduced by 1 stop. Refer to the camera and lens instruction booklets to see if there are any AF compatibility limitations due to the reduced max aperture.

Autofocus will also work given that you have enough light for the camera to be able to focus and you are using the largest aperture possible.
As far as I can see, the camera limits the autofocus to a 5.6 aperture
You will also get a lot more information from this answer: https://photo.stackexchange.com/a/16400/26160

Autofocus with canon EOS 1200d


What's the purpose of the cover on the catalytic converter?

Question: On my 1990 Honda, it's falling apart. I'd like to just rip it off; will that cause any problems? More specifically: will the car pass New York state inspection with a missing cover?
Answer: I can't tell you if it'd fail inspection or not, but there's a good reason for its existence.
It's basically a heat shield that protects the body of the car and the carpet/sound deadening in the car from the heat of the cat. Catalytic converters can get very hot (in the worst case, glowing hot) and without the heat shield that can cause problems or at least discomfort.
I'd try to see if you can find a replacement at a junk yard or on ebay from somewhere less corrosion-prone.
Comment: The bottom of the shield helps prevent fires in tall grass.
Comment: ^ this was surprisingly common when cats were added and/or engines were leaned out to meet emissions standards in the 70's and 80's.


Background effect in CSS

Question: I found this site: https://jonasreymondin.com/ (It isn't mine, It just random site I found)
In the background there is a strange effect, I have no idea what it's called or how to do it, does anyone know anything?
I am talking about dot/glitch effect (you have to be careful to notice it), not the parallax effect.
I found this line of code, by deleting this line the effect disappears:
<canvas class="grain" width="976" height="927"></canvas>
I search in the code what that tag do but I don't found anything.
Answer: You can check this js pen here, it meight help

      <canvas id="canvas"></canvas>

Answer: It is a canvas code, if it is an external plugin you may need to install it or else you need to copy the code.
Ref Link

Background effect in CSS


How to select non-consecutive text in OS X

Question: In Windows I would hold the ALT key to highlight non-consecutive (or non-contiguous) text pieces, but how can I achieve this in the latest OS X (mavericks)? If it's any consolation, I'm trying to achieve this in Word, however I'd like it to be a universal function if possible.
Answer: To solve your problem in Word (and TextEdit and other word processors...), just use Cmd + Select letters/words with mouse:

You cannot have a universal shortcut AFAIK, because developers need to use something called NSTextView in their apps (which they don't for some reason beyond me...).
Comment: Fantastic, thank you. I will tick if no one else comes up with a universal method. +1


Graph Theory: Isomorphism

Question: I am trying to do MIT ocw course 6.042: Math for CS. Could anyone help with this one? I couldn't really understand the concept of isomorphism. What exactly do they mean by " preserved under isomorphism"?.
Determine which among the four graphs pictured in the Figures are isomorphic.
If two of these graphs are isomorphic, describe an isomorphism between them. If they are not,
give a property that is preserved under isomorphism such that one graph has the property,
but the other does not. For at least one of the properties you choose, prove that it is indeed
preserved under isomorphism (you only need prove one of them).

The graphs are given below in the link:
It is from MIT 6.042 Problem set 4. Problem 3 Part(b): http://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-042j-mathematics-for-computer-science-fall-2010/assignments/MIT6_042JF10_assn04.pdf
Comment: If every graph isomorphic to a given graph with Property P has Property P, then we say Property P is preserved by isomorphism. For example, every graph isomorphic to a graph with 17 vertices has 17 vertices, so having 17 vertices is preserved under isomorphism.
Answer: https://en.m.wikipedia.org/wiki/Graph_isomorphism
The Wikipedia article gives the definitions but they may not be easy to understand. The basic intuition is that if you can move the vertices of a graph without changing the connections between vertices and edges so that the graphs look the same, then they are isomorphic. In other words, take any graph you know and move one of the vertices to the other side. All the connections and other properties will be the same but it will look different.
Answer: $G_2$ has vertices with $4$ outer-edges (namely, 10 and 8), and the other graphs don't.
$G_4$ has $4$-cycles (e.g. 3-4-10-8), and $G_1$ and $G_3$ don't.
$G_1$ and $G_3$ are isomorphic. I'll let you try to figure out the isomorphism yourself. You can use this tool: https://illuminations.nctm.org/Activity.aspx?id=3550 to draw the graphs and move the vertices around, which should help you find an isomorphism.

Hint: one possible isomorphism, in the firection $G_1\to G_3$, maps $1\mapsto 1$, $2\mapsto 2$, $3\mapsto 3$, $4\mapsto 4$, $5\mapsto 10$).
Comment: I tried to see the isomorphism between G1 and G3 but could not see it. I played with G1 and G3 in the animation link but these don't look isomorphic. I am comparing vertex 1 in G1 with vertex 1 in G3. Can it be that that e.g vertex 3( or any other no.) in G1 is related to vertex say 5 in G3? I If yes, then there are just too many possibilities to check.  And yeah thanks for the great link.
Comment: @Solomon You can draw $G_1$ in the tool and move vertices 1 to 5 around, as in the  hint, so that they are in the same position as its image in $G_3$. Then you simply need to move the other ones around in order to obtain $G_3$, and this will give you the isomorphism. For example, in $G_3$, the vertices 1,3 and 6 are connected to 2. The hint already states that 1, 2 and 3 in $G_3$ are associated to 1, 2 and 3 in $G_1$, so 6 in $G_3$ will be associated with the only other vertex connected to 2 in $G_1$, namely 9. You can continue these arguments and find the remaining associations of vertices.

Graph Theory: Isomorphism


Topology such that function is continuous if and only if the restriction is.

Question: Let $X$ be a topological space and $A \subset X$. If $f : X \to Y$ is continuous, then $f|_A$ is automatically continuous (where $A$ has been equipped with the subspace topology). What about the converse? That is, for a fixed $A \subset X$, is there a topology on $X$ such that $f : X \to Y$ is continuous whenever $f|_A : A \to Y$ is?
Comment: Yes. You can equip $X$ with the discrete topology, but this is not very enlightening since every map from the discrete topology is continuous.
Comment: Of course. I should have asked for the coarsest such topology.
Answer: Any function $f : X \to Y$ with $X$ discrete is continuous.
For general $X$ and $Y$, for the converse to hold, you need $A$ to be an open subset of $X$. To see why, let $f = 1_A : X \to \{0,1\}$ be the indicator function
$$1_A(x) = \begin{cases} 1 & \text{if}\ x \in A \\ 0 & \text{otherwise} \end{cases}$$
and endow $\{0,1\}$ with the discrete topology. Then $f|_A$ is constant, hence continuous, and so $A = f^{-1}(\{1\})$ is open in $X$.
Comment: @user95483: I can't speak for Clive, but I don't think that I've ever seen it. I think that it's more a matter of experience: if you realize that continuity on $A$ really doesn't tell you anything about how the function behaves on the rest of $X$, it's not hard to guess that you'll need a topology on $X\setminus A$ that lets just about any function be continuous on $X\setminus A$, and that means that $X\setminus A$ probably has to be discrete. At that point it's just a matter of finding a way to prove the insight.
Comment: Ok, $f|_A$ is constant, so it is continuous as $\{0, 1\}$ has the discrete topology. So $A$ must be open in $X$. This is necessary, but is it sufficient?
Comment: Absolutely not! For instance, the indicator function of $(0,1)$ as a subset of $\mathbb{R}$ is not continuous. In general, if your topology on $X$ is fixed, then there isn't much more you can say.
Comment: ...as a really silly example, take $A = \varnothing$. Any function whatsoever is continuous when restricted to $\varnothing$ (it's the empty function), and so you can't say anything at all about the function you're restricting!
Comment: @user95483: Suppose that $A\subsetneqq X$, and let $x\in X\setminus A$. Let $f$ be the indicator function of $\{x\}$; then $f\upharpoonright A$ is continuous, but $f$ is continuous iff $x$ is isolated. Thus, you need $A$ to be open and $X\setminus A$ to be discrete.
Comment: Thanks Clive and Brian. Is this a well-known result? You guys came up with it really quickly.
Comment: I'm having a hard time showing these conditions are sufficient,
Answer: What you are searching for is the so-called final topology. Imagine you have a set $X,$ a space $A$ and a map $i:A\to X.$ Then you can equip $X$ with a topology such that every function $g:X\to Y$ into a space $Y$ is continuous if and only if $g\circ i:A\to Y$ is continuous. It is easy to prove that a topology with this property is unique. We can also show that it exists, namely the open sets in $X$ are defined to be the sets $U$ such that $i^{-1}(U)$ is open in $A.$
In the case that $A$ is a subspace of $X$ and $i:A\hookrightarrow X$ is the embedding, then the restriction $f|_A$ can be expressed as the composition $f\circ i.$ Then the final topology will have as open sets all sets $U$ of $X$ such that $i^{-1}(U)=U\cap A$ is open in $A.$