Would a question asking what's the hardest game in a genre be on-topic?

Question: So asking relative question about what's the hardest game and everything acceptable? I'm new here so feel free to edit my question if you want.
Comment: Those are subjective, what you think is hardest isn't necesarily going to apply to what I think is hardest.
Answer: Asking what the hardest game in the genre wouldn't be acceptable for a few reasons, but the two main ones are that it's a game recommendation and is too subjective. Everyone is going to have a different idea of what's considered the hardest game in the genre, and some games one person considers really easy others will consider really hard. Due to this all answers will just be users posting their opinion, which isn't really what SE is meant for.
With that said, you'd be welcome to pop into our chat room and ask for users for opinions there. Another good option would be /r/shouldibuythisgame, which is subreddit for suggesting people games to play.


How can I jump to a given year on the Google Calendar application on my Google Pixel 6 phone?

Question: I  use the Google Calendar application on my Google Pixel 6 phone. Sometimes I want to look at some event a few years ago. How can I jump to a given year on Google calendar?
Comment: On the web, you can press the `g` key to go to a particular date.
Answer: From Google support How to navigate to a specific date in google calendar Android app. E.g going to Aug-14&seeing events

... there's no way to do this in the Android app, but you can ask Google Assistant to list events from a given month or date. For example : "OK Google, show my events in August this year", then click on a result to open that event.

I didn't fully verify this as I don't use Google assistant but by invoking it on long press of home, and keying in as advised, I could see events upto two years ago.
Comment: The fact that the android app doesn't allow this is so stupid. It would be so easy to implement a picker that you could show tapping on the top bar to select a date and move the calendar to that date, like the material date picker.
Comment: This is not an answer the question, since that is app specific. However a 3rd party app like aCalendar (which is just another frontend for google calendar) offers years to pick from the hamburger menu, which might be quicker for selecting a specific year than an assistant. Maybe it is worth taking a look at this or other such apps.


Is there a rule prohibiting "follow-ups"

Question: My question was closed, with my requests for reopening being declined even after resolving every concern presented, except one. This stated that I cannot have multiple answers, with the person stating this saying that I was asking 3 questions, one being the main, one being a request for explanation, and another being a question about whether my idea is hard to prove/disprove. Is this a good reason to close my question, and/or is asking "multiple questions" not allowed?
Comment: Have you read our [help]?
Answer: Yes
When you say "follow-up" I assume what you mean is that, within a single post, you're asking a "main question" with one or more "follow-up" questions. I say this because asking a second, independent question on Main that is a "follow-up" to a previously asked question is completely permissible.
So, yes, they're a reason to close a question. If you click on the "Close" link on any question you'll find the following:

Needs more focus
This question currently includes multiple questions in one. It should focus on one problem only.

In other words, asking more than one question, no matter how related, is a technical infraction of Stack Exchange's rules. Note, Stack Exchange, not Worldbuilding.SE. It's not our rule, it's network-wide.
If you think this discussion is messy, search Meta for "Opinion-Based" and look at the dozens of discussions we've had about that network-wide close reason on a site that has a tag for "Magic."
Let's look at what you state are the three questions you feel should be permissible.

The main question

Can white holes travel faster than the speed of light?

A request for an explanation

And if this effect doesn't apply, then what is it that bounds them to traveling slower than the speed of light?

"Whether my idea is hard to prove/disprove" (a request to review the idea)

do you think that I could get away with using this idea anyway?

Had it been asked better, question #1 isn't a bad fit for this site. My original problem with the question (and the reason I voted to close the question) is that you appeared to be asking for a factual answer involving a fictional issue. That's better addressed by Physics.SE or Astronomy.SE. Your original post didn't make it clear that you were writing a story, building a world, or that you know negative mass, etc., isn't real.
I remain a bit unconvinced that you understand the difference between a mathematical hypothesis and empirical evidence. The first is fiction until proven otherwise. The second is fact. If I'm wrong about this perception, I very much apologize. If I'm right, it's important that you learn to understand the difference.
Since, as the Help Center explains, our goal is to help people build imaginary worlds, we became stuck with what to do with your question. Because you presented yourself as believing the hypothesis was real, what you needed was an educational experience to help you better understand the issue. But that's not within the scope of our Stack. Technically, it's not within the scope of any Stack. Stack Exchange wants people to ask specific and reasonably objective questions that meet the expectations of the individual Stacks.
Which brings us to question #2. Giving you an education about astrophysics is not why we're here. Per the Tour, Stack Exchange is not a discussion forum. Per the Help Center, any question that can be reasonably answered with a book-length response is out of scope. It's a long way of again saying we're not here to give you an education.
As a quick aside, this is why we have problems with "tell me what's wrong with my idea" questions. The Help Center states that questions should not be asked in a way that produces answers of equal value. Infinite lists of things questions (meaning questions that are not asked with the expectation of a single, best answer) are off-topic here and "tell me what's wrong with my idea" questions are of that type.
The last question is scratching an itch that we haven't solved, yet. We're still thinking about review my idea questions. The problem is that they don't fit the Stack Exchange mold. Remember, Stack Exchange wants one specific reasonably-objective problem that needs a solution. In fact, it's intent is to be the go-to place to find solutions to problems. From their perspective, your individual desires don't come into this. From our perspective, we know that a creative process like worldbuilding must balance the individual needs of the querent with the business expectations of Stack Exchange.
To a degree....
So, yes, there is a rule against "follow-up" questions in the way that you're using the phrase. You're allowed to ask one and only one question per post. We're usually lenient with new users, but there were many other things wrong with your question, too.
I wish you'd asked this first in our Sandbox. The Sandbox's purpose is to help people learn how to ask questions on this site to meet our expectations while adhering to Stack Exchange's business model. All this could have been ironed out before you met your first slammed door (closed question). I still recommend it. We're happy to help you be successful — within the limits of Stack Exchange's rules and our policies.
Comment: Compulsory reference to further explain the difference between facts and worldbuilding : https://worldbuilding.meta.stackexchange.com/q/10202/80336 . I source this post more often than I would have expected, proof it's useful :).
Comment: @WhatsYourIQ192 I'm an electrical engineer. Our world is simple: show me the proof. Negative mass, dark matter, wormholes. They're all hypothesized mathematically, but until someone can show us one that can be tested, measured, and physically used - they're not real. Therefore, asking us to treat them as if they are real is unrealistic (and out of scope).
Comment: @Tortliena That's a very good point! :-)
Comment: Thank you, I was unaware of the sandbox and I will try to reformat it there. But I still must say, people have theorized ways to make negative gravity, so negative mass should not be so quickly dismissed as not real.
Comment: That is a common fallacy, argument from ignorance (https://en.m.wikipedia.org/wiki/Argument_from_ignorance), when one claims that absence of evidence is evidence of absence.
Comment: @WhatsYourIQ192 Please stop being juvenile. The scientific method doesn't recognize logical fallacies. It does recognize empirical evidence - which you don't have. You don't know negative mass is real, you believe it's real. Welcome to the Religion of Science. It hasn't been around as long as Christianity, Islam, or Judaism, but it's making up for lost time. Now, if you don't mind, the entire Stack isn't going to change to make you happy. You, on the other hand, have the privilege of working within the structure of the stack, or finding someplace else.
Comment: A long time ago, people didn't know that there were planets other than the ones in our solar system. Does this make them nonexistent? No. Does this make them scientific? Also no. While we have never found these things, that does not mean they are not real. Is that good enough evidence for you?
Comment: I am not saying that they are real, I am simply saying that until you can prove they are impossible, you cannot say that they do not exist.
Comment: @WhatsYourIQ192 In the perspective of how this Stack operates, yes I can. In general life, I can trivially take the stance, "you can't treat them as real until you prove that they are" and ignore as childish any response along the lines of, "until you prove they don't exist, I can." I'm going to have trouble proving fairies exist - but you'd be acting (to make a point...) like a 5-year-old to claim it's my job to prove their non-existence or to accept your firm belief that they're real.
Answer: Yes there are rules prohibiting multiple questions
If you are talking about this question, and that by follow-ups you mean asking multiple questions that follow one another, the answer is no, you cannot ask follow-ups within the same post as the main question. Let's start with the reference rules :

General guidelines for all questions

[your question] Must be specific and answerable: What problem are you trying to solve?
From the help-center : what topics can I ask about here?

Your question should be specific. Also note that "problem" is singular, with no "s".

What types of questions should I avoid asking?
You should only ask practical, answerable questions based on actual problems that you face. Chatty, open-ended questions diminish the usefulness of our site and push other questions off the front page.
Your questions should be reasonably scoped. If you can imagine an entire book that answers your question, you're asking too much.
From the help-center (again!) : what types of questions should I avoid asking?

Asking multiple questions will tend to make it chatty. Moreover it makes answers much longer than necessary. As told in the tour, the motto of Stack-Exchange is "Ask questions, get answers, no distractions". The goal is to be as straightforward as possible in both questions and answers, and the site is designed for that. Multiple questions in a row tend to attract more questions both from you and answerers, creating long, unreadable threads of comments at best, mangled up mix of answers we don't know what was the question at worst. That's one big reason why it's forbidden.
Finally, know that the community is not overly pedantic. As such some edge-cases are allowed if each question are extremely closely related. For instance : "What is the maximum height of my ogre species? Can it reach the height of an elephant?" Answering the first question effectively answers the second, making this 2nd question more like a writing style to add additional details about what you want (➡ I wish to make my ogres as big as elephants). This is not really a standalone question anymore. For the other cases... Well, consider you cannot ask them in the same post.
The solution
The solution to this issue is actually quite simple : Don't jump over horses, sharks and sheeps three at a time. Asking two questions at once is not really useful anyway if your 1st question get good answers which are yet inadequate for the 2nd query. Ask your main question, wait for answers, see if you need to know more, then write a second post with your follow-up question. This has been done with success a numerous amount of time.
If you wish to, you can succintly relate one question to another with a link. Just remember that each and every question should hold its own alone, so if you need important details in one question to ask another, you'll have to restate it. This is in part to prevent broken links from making your question unreadable at much later dates... And because it can be annoying to have multiple tabs open to follow you, too .

Is there a rule prohibiting “follow-ups”


tata cdma iPhone 5 model no a1429

Question: I have purchased iPhone 5 CDMA handset model no A1429 and its an unlocked one which i wish to use in India with Tata CDMA sim, please let mme know the activation process for the same as there is no sim slot for CDMA, some configuration method is required to activate it.
Answer: In the settings app, get the MEID and have your cellular carrier provision for that number.
CDMA isn't something you can self enroll unless your carrier lets you enter that information into a web portal or other self-service kiosk.
In the US, CDMA carriers still put in a SIM which carries an IMEI for the appropriate carrier, but I don't recall ever having them request that number.
In short, contact your local carrier for assistance.

tata cdma iPhone 5 model no a1429


How to get the value of a "transfer_all" transaction?

Question: my question is regarding Polkadot, I need to get the value of any "transfer" transactions and there's no problem with it with "transfer_keep_alive" and "transfer" transactions. On "transfer_all", however, extrinsics don't contain the "value". I got a clue that I need to get events of a block via state_getStorage RPC method, but I'm struggling with which keys I should provide as params. There's not much info in docs about it. Also, I'm not using a polkadot-js lib and only use HTTP RPC requests. How do I get the events for the block via state_getStorage method?
Comment: Please edit the question to limit it to a specific problem with enough detail to identify an adequate answer.
Answer: You can just use Substrate API Sidecar's GET block endpoint. It will give you all the events associated with each extrinsic.
Sidecar is stateless and requires very few system resources. Just give it a WS connection to a node and use the Sidecar API.
Comment: Can't use it for my use case as I can't have WS connections (hence "I'm not using a polkadot-js lib and only use HTTP RPC requests"). There are several ways I could get these events from API, however, the easiest of the ways are not available for me.
Comment: They are under `system.events`: `0x26aa394eea5630e07c48ae0c9558cef780d41e5e16056765bc8461851072c9d7`
Comment: Yes, there is an RPC method ```state_getStorage``` that supposedly should allow to request events. However, there is very little documentation of what are the "keys" that are supposed to be associated with certain data in storage. On my Polkadot node the ```state_getKeys``` method, which is supposed to be called with 0 arguments, returns an error that it expects 1 or more arguments. Seems like the documentation is partially deprecated, since my node is running the latest version.


Bluetooth pairing without user confirmation

Question: Can I pair two devices over Bluetooth without a need to confirm this in user interface, accept to pair this devices. Can I exchange some extra data over, for example NFC, and then safely pair those two devices over Bluetooth without any extra user action?
Comment: Smells like security breach, although I'm sure that Bluetooth technology has a ton of holes in it. I'm not sure that's legal though, and you application will most likely be removed from Android Market.
Answer: This need is exactly why createInsecureRfcommSocketToServiceRecord() was added to BluetoothDevice starting in Android 2.3.3 (API Level 10) (SDK Docs)...before that there was no SDK support for this.  It was designed to allow Android to connect to devices without user interfaces for entering a PIN code (like an embedded device), but it just as usable for setting up a connection between two devices without user PIN entry.
The corollary method listenUsingInsecureRfcommWithServiceRecord() in BluetoothAdapter is used to accept these types of connections.  It's not a security breach because the methods must be used as a pair.  You cannot use this to simply attempt to pair with any old Bluetooth device.
You can also do short range communications over NFC, but that hardware is less prominent on Android devices.  Definitely pick one, and don't try to create a solution that uses both.
Hope that Helps!
P.S. There are also ways to do this on many devices prior to 2.3 using reflection, because the code did exist...but I wouldn't necessarily recommend this for mass-distributed production applications.  See this StackOverflow.
Comment: You my friend are a genius.  Adding one word to my code ("Insecure" as in createInsecureRfcommSocketToServiceRecord()) made my legacy bluetooth device (GPS) work immediately.  It does not need a PIN code, so the secure connection was not working.
Comment: Hi, Can you please tell me, if there is some BroadcastReceiver kinda thing available to know if some paired device is available? If not then, I think, I have to do a periodical polling which involves trying to connect to the required device. But connect is a blocking call and it will also set the toll on battery.
Answer: Well, this should really be broken into 2 parts:

Can you pair 2 Bluetooth devices without going through a Bluetooth pairing handshake? No, you can't. That's baked into the protocol so there is no way around this.
Can you perform the handshake without a user interface? Yes, you can: that's just code.

I'm not sure how you do it in Windows land, but in *nix land there are functions buried in the Bluez stack that let you receive notifications about when a new device appears, and send it the pairing code (clearly there have to be these functions: those are what the user interface use). Given sufficient time and experience I'm sure you could figure out how to write your own version of the Bluetooth Settings app that somehow:

Detected a new device had arrived
Looked at the name/bluetooth mac address and checked some internal database for the pairing code to use.
Sent the pairing code and completed the operation

All without having to pop up a user interface.
If you go ahead and write the code I'd LOVE to get my hands on it.
Comment: Hi, I am up for this even if you have little bit excitement. I am working on this currently in cordova. If you are available we can do this.
Answer: Short answer: When I send files between devices with OBEX I am almost never prompted to pair, so it is certainly possible.
1) An application and the device itself can each be set to need/not-need authentication modes, so often there was no requirement for pairing.  For instance most OBEX (OPP) servers don't need any authentication at all so there is not need for pairing/bonding.
Presumably "Wireless Designs"'s answer was covering that case.
2) Then if pairing was required by the device/app:
2.1) Prior to v2.1 for pairing then the two devices needed to have matching passphrase/PINs.  So this either needed user involvement (to enter the PINs) or knowledge in the softwareto know the PIN: either defined in the app if pin callback send pin="1234", or smarts in the OS like BlueZ and Win7 (see Slide 20 at my Bluetooth in Windows 7 doc) which has logic like: if(remotedevice=headset) then expectedPin ="0000".  Don't know what Android does
2.2) In v2.1 Secure Simple Pairing (SSP) was added.  Which changes pairing to:

if (either is pre-v2.1) then
   Legacy
else if (Out-Of-Band channel) then
   OutOfBand
else if (neither have "Man-in-the-Middle Protection Required") then
   (i.e. both have "Man-in-the-Middle Protection _Not_ Required")
   Just-Works
else
   Depending on the two devices' "IO Capabilities", either NumericComparison or Passkey.
   Passkey is used when one device has KeyboardOnly -- and the peer device _isn't_ NoInputNoOutput.
endif

From 32feet.NET's BluetoothWin32Authentication user guide, see also the SSP sections in [1]
So to have pairing be unprompted needs either "JustWorks" or "Out-of-Band" eg your NFC suggestion.
Hope that helps...
Answer: Yes it is possible in theory as defined by the specification.
However there is no practical implementation as yet that would allow this.
Refer: NFC Forum Connection Handover Technical Specification
http://www.nfc-forum.org/specs/spec_list/
Quoting from the specification regarding the security -
"The Handover Protocol requires transmission of network access data and credentials (the carrier configuration data) to allow one device to connect to a wireless network provided by another device. Because of the close proximity needed for communication between NFC Devices and Tags, eavesdropping of carrier configuration data is difficult, but not impossible, without recognition by the legitimate owner of the devices. Transmission of carrier configuration data to devices that can be brought to close proximity is deemed legitimate within the scope of this specification."
Answer: BT version 2.0 or less - You should be able to pair/bond using a standard PIN code, entered programmatically e.g. 1234 or 0000. This is not very secure but many BT devices do this.
BT version 2.1 or greater - Mode 4 Secure Simple Pairing "just works" model can be used. It uses elliptical encryption (whatever that is) and is very secure but is open to Man In The Middle attacks. Compared to the old '0000' pin code approach it is light years ahead. This doesn't require any user input.
This is according to the Bluetooth specs but what you can use depends on what verson of the Bluetooth standard your stack supports and what API you have.
Answer: If you are asking if you can pair two devices without the user EVER approving the pairing, no it cannot be done, it is a security feature.  If you are paired over Bluetooth there is no need to exchange data over NFC, just exchange data over the Bluetooth link.
I don't think you can circumvent Bluetooth security by passing an authentication packet over NFC, but I could be wrong.
Comment: It seems that you were wrong. According to what I read on this page, the insecure bluetooth connection enable a communication without security, and the NFC connection can let both cellphones create a shared secret which can be used to encrypt the communication over bluetooth using a symmetric cipher like AES.


Are total cross-sections useful (experimentally verifiable) observables?

Question: I understand that differential cross-sections such as $$\frac{\partial \sigma}{\partial \Omega}\left(\theta,\,\phi\right)$$ are useful observables. But if we only know $\sigma_{\text{total}}$, the total cross section for a process, is that something we can experimentally verify? Or are total cross sections only useful in ratio with other total cross sections, such as (for instance)$$
\frac{\sigma \left(e^+e^- ~ \to ~ \text{hadrons}\right)}{\sigma\left(e^+e^- ~ \to ~~~ \mu^+ \mu^- ~~\right)}
\,?$$
Comment: Are you asking whether total cross sections are "useful observables" (as in the title), or whether they are experimentally verifiable? If the former, I'd suggest using more precise wording in the title.
Answer: Merriam-Webster's definition of "useful":

Definition of USEFUL

capable of being put to use; especially : serviceable for an end or purpose $\bullet$ useful tools
of a valuable or productive kind $\bullet$ do something useful with your life

For "cross section":

a measure of the probability of an encounter between particles such as will result in a specified effect (such as scattering or capture)

So a total crossection will answer on how probable an interaction between two specific particles is. The size will define whether the interaction is weak, strong or electromagnetic,  so even if only the total cross section is known or can be calculated there is useful information for subsequent studies.
Edit after edit of question, defining usefull as "experimentally verifiable".
Yes, they are. Look at this table in the particle data group listing total crossection for particles scattering off each other,as an example, proton proton scattering:

As the definition of crossection says, it is proportional to the probability of scattering off each other.
.
Comment: Thanks. I've edited my title to include "experimentally verifiable." So are total cross-sections experimentally verifiable? Or only the ratio of different cross-sections?
Answer: Yes, they are experimentally verifiable.
If you have a beam of one of the particle species, and a thin plate of thickness $dx$ and number density $n$ of the other, and you're looking at a process of total cross-section $\sigma$, then the probability the particle interacts is given by:
$$ dp=n\sigma\,dx$$
or, in other words, the characteristic length scale of the interaction is:
$$ \lambda=n\sigma $$
Many experiments these days collide two beams rather than a beam and a fixed target, but using relativity you can relate the two- essentially by considering the interaction from the reference frame in which one beam is fixed.


Zero by zero division and complex variable.

Question: To my knowledge, zero divided by zero is neither zero, nor infinity, it can't be understood.
Let a complex function of a real variable $w$ be
$$
Z(w) = iw = 0 + iw
$$
Now, generally the argument of this variable is $ \arctan (\frac{w}{0})  = 90^\circ $. Now, if $Z(w)$ is a transfer function and I'm measuring the frequency response phase angle at $w = 0$, How is $\angle Z = 90^\circ$, given that at $w=0$ the argument becomes $\arctan(\frac{0}{0})$ ?
Comment: $\arctan (\frac{w}{0})  = 90^\circ$ is wrong because $\frac w 0$ is undefined. And the complex number $z=0 + i0$ does not have an argument.
Answer: You don't need a division to define an argument, as it would be generally better to use the double argument arctangent function.
This way: $\angle Z =\arctan2(w,0) = 90^\circ$ if $w>0$.
If $w=0$ as well, then the argument of the complex number is undefined, but you might just use a convention to say it is zero or other convenient value for some special application, since it also has no radius, it should hardly matter,
Comment: O yes! I see, I was thinking about the frequency response of a pole at origin, frequency response doesn't care about w=0, so as a convention we take it as 90 degrees, it doesn't matter like you said.


Error: Import failed: cannot deserialize value, string is corrupted during setup:upgrade

Question: I have an error during the setup: upgrade more precisely at this specific location
**Module 'Mageplaza_OrderExport':
Processing configurations data from configuration file...
Import failed: Unable to unserialize value, string is corrupted.
app:config:import failed. See previous output.
**
this follows a config change on the env.php where I changed the session save to db instead of file
I don't think this has an impact on the setup:upgrade
Thank you in advance for your help.
when I put back the file value I have this error Exception: Warning: SessionHandler::read(): open(/var/lib/php/sessions/sess_s99guge050hkcpvgbmf3sj53qr, O_RDWR) failed: Permission denied (13) in /home/var/ www/html/magento2/provider/magento
Update: I found the problem which was to put the rights on the sessions folder but now I have a problem of no style on my site
[1]: https://i.stack.imgur.com/p9bZ4.png
and also the admin page is not found.
Answer: Update:
I found how to solve this problem, you have to run this command app:config:dump and then run this command app:config:dump and finally the command upgrade


E(XY)=E(XE(Y|X) Joint Conditional Expectations

Question: Why is E(XY)=E(XE(Y|X))?
Is this using the properties of conditional expectation and is there a general formula that can be applied when you have E(...)=E(..(E(Y|X))?
Answer: By the expression $\mathbb{E}(XY),$ we mean the expectation of XY under their joint distribution. I.e., if these both are continuous, we have that
$$
\mathbb{E}(XY) = \int\int xyf(x, y)dxdy,
$$
where $f(x, y)$ is the joint pdf of X and Y. For this reason, we sometimes write $\mathbb{E}_{(X, Y)}(\cdot),$ or $\mathbb{E}_f(\cdot)$ in order to make it explicit which distribution the expectation is to be taken over.
We can factorise distributions in a certain way, specifically we can write the pdf of a $d$-dimensional continuous random vector as
$$
f(x_1, \dots, x_d) = g_1(x_1)g_2(x_2\vert x_1)g_3(x_3\vert x_2, x_1)\cdots g_d(x_d\vert x_1, \dots, x_{d-1}).
$$
Applying this to $(X, Y),$ we can write $f(x, y) = g(x)h(y\vert x).$ We can then see that
\begin{align*}
\mathbb{E}_{(X,Y)}(XY) &= \int\int xyf(x, y)dxdy\\
&= \int\int xyg(x)h(y\vert x)dxdy\\
&= \int x\int yh(y\vert x) dy f(x)dx\\
&= \mathbb{E}_X\left(X\int y h(y\vert x) dy\right)\\
&= \mathbb{E}_X\left(\mathbb{E}_{(Y\vert X)}\left(Y\right)\right).
\end{align*}
This is also true for distributions that are not continuous, and can be generalised to a higher dimension analoguosly to the factorisation property of distributions. To show this in a very general context, you need some measure-theoretic arguments. The general formula that you request is often referred to as the law of iterated expectations,
the tower rule, the smoothing theorem, or the law of total expectation.
Answer: Another way to show it is directly using Law of iterated expectations:
$$\begin{align}E[XY] &= E[E[XY|X]]=E[XE[Y|X]]\end{align}$$
Comment: Thank you. Could we similarly have E(XY)=E[E(XY|Y)]=E[YE(X|Y)]
Comment: yes, exactly, it holds both ways.


Why do $S_x$ and $S_y$ flip up/down spin states but $S_z$ does not?

Question: By using the notation $S\lvert s,m_s\rangle$, such that $\bigl\lvert\frac{1}{2},\frac{1}{2}\bigr\rangle=\lvert+\rangle$ and $\bigl\lvert\frac{1}{2},-\frac{1}{2}\bigr\rangle=\lvert-\rangle$ we can obtain following the eigenvalue equation for the components of the spin vector:
$$\begin{align}
S_x\lvert\pm\rangle&=\frac{\hbar}{2}\lvert\mp\rangle \\
S_y\lvert\pm\rangle&=\pm i\frac{\hbar}{2}\lvert\mp\rangle \\
S_z\lvert\pm\rangle&=\pm\frac{\hbar}{2}\lvert\pm\rangle
\end{align}$$
However, I am struggling to interpret the result. If we consider the $x$ and $y$ component of spin, then there seems to be flipping of the state function, but it's not the same for the $z$-component. Why is that?
Answer: You chose the $\lvert \pm \rangle$ to be an eigenvector of $S_z$ with eigenvalue $\pm\frac{1}{2}$ - that's what the $m_s$ is: The eigenvalue of the state w.r.t. the $z$-spin.
Since $S_x$ and $S_y$ do not commute with $S_z$, $\lvert \pm \rangle$ is not an eigenvector of them, hence the state cannot stay the same after they are applied to it.
That the spin is precisely flipped comes from the form of the commutation relations
$$ [S_i,S_j] = \mathrm{i}\epsilon_{ijk}S_k$$
and you can see that the spin is flipped by evaluating $S_z$ on $S_x\lvert \pm \rangle$ and $S_y\lvert \pm \rangle$.
Comment: why we did not choose ∣±⟩ to be an eigen vector of $S_x$ or $S_y$, I am sorry, but I am still struggling to grasp the answer.
Comment: @RoshanShrestha: You can as well choose it to be an eigenvector of any of those, or an eigenvector of the spin about any other axis. There's nothing distinguishing a special direction. You just need to pick *some* direction to talk about whether the spin is "up" or "down" compared to that direction, and we conventionally call that direction $z$.
Comment: Thanks, Can we physically interpret the above result as in Stern Gerlach Experiment ?


zimbra conflicts with the old email server

Question: I recently installed Zimbra.I have been setting up for each toplevel domain the new mx record and ip, than on Zimbra I have been migrating the old email addresses. When I send an email to existing account the mail is getting recived by old email server. If I test the the mx domain mxtoolbox shows the desired one. I have been running the emails previously on hmail and icewrap.
Answer: You are probably seeing issues with DNS caching. Each DNS record has a TTL field, which says to anyone requesting, this record should be valid for this amount of time. Usually if left unchanged, it is 24 hours. While the ttl is still valid, a recursive DNS server will not go and see if anything has been changed in the zone file.
The simplest thing to do is to try and reduce the TTL for the domains you are migrating, at least 48 hours before actually making changes, that way you can be sure that remote DNS servers will make a "fresh" request to your DNS server much more quickly.
The other thing you can do is set up your old email server to forward any email for moved domains to the new server. In postfix this is fairly simple, but you didn't mention what your old server was.


How to exclude API users from Federated SSO

Question: We have implemented Federated SSO for all our users with our Identity management and got stuck with few API users who interact with salesforce with API only, how can we exclude certain users from SSO and use default login. As far i have read the details only Delegated SSO lets me exclude users and for Federated SSO i dont have option to exclude specific users (Its either all or none). Can anyone tell their experiences or best practices for API users in Federated SSO
Answer: 1.Make sure your API users does not have Federated Id populated .In other terms leave that as blank .
2.In My domain make sure , Prevent login from https://login.salesforce.com option is unchecked so users can use login.salesforce.com to login .
Comment: but wouldnt that let any user in the org to login through login.salesforce, i am hoping i can only let API users use the login.salesforce and rest enforce they come in only through SSO. Its creating a security if i let users login using login.salesforce.com. Any way i can restrict for all users but not few?
Comment: Try with step 1 only and making federated I'd blank and use login.salesforc.com to log as admin .My assumption is that should allow admin to log in .
Comment: Also how about for those users make them API only users via there profile .I think to make them API only users you will need to close the profile and an API only users cannot use Salesforce UI
Answer: Thanks for comments and inputs, figured out finally! Below setting in SSO only prevents user logins through UI and our API logins remains unaffected, i.e even after enforcing 'Prevent login from test.salesforce' we are still able to make API calls to that end point, i believe this setting is not applicable to API calls and we able to use salesforce username password for the oAuth flow for the connected app. So i believe its safe to say that 'UI logins' are SSO enforced by Federated SSO but API logins can still be used with salesforce credentials.
Hope salesforce can mention this in any documentation of help text next time for others not to get confused
Comment: The help text next to the Login Policy checkbox reads:  `This applies to every login except SOAP API`.  So if you're using the REST API I suspect this will not work.
Answer: My understanding is that public domain restrictions apply for both browser AND API.
However, federated SSO can be made mandatory on a profile-base


Where are raster pixel values stored in PostGIS?

Question: I have several raster images of temperature, they are stored as geotiffs and I import them to a PostgreSQL database using raster2pgsql.
raster2pgsql -s $SRID -t auto -I $file $SCHEMA.$(basename $file .tiff) | psql -U $USERNAME -d $DATABASE -h $HOST -p $PORT

But when I look at the data using pgadmin I see only an ID and rast column and no temperature values.
Using QGIS I can display original geotiff without any problems.
Any idea what is going wrong?
Answer: The values are stored in the raster object itself. You can access them using the ST_Value function which accepts column and row indexes or point geometries.
The ST_Value documentation has some good examples.
Answer: For getting all the values of the pixel you can do something like the following:
SELECT x, y, ST_Value(rast, 1, x, y) As value_band1,
    ST_Value(rast, 2, x, y) As value_band2,
    ST_Value(rast, 3, x, y) As value_band3
FROM your_raster_table_name
CROSS JOIN generate_series(1, 1000) As x
CROSS JOIN generate_series(1, 1000) As y
WHERE rid=1 AND x <= ST_Width(rast) AND y <= ST_Height(rast);

If your raster have only one band, then only select the value_band1. You can check some metadata and also the number of band used in your raster table by following code.
SELECT rid As r, (rm).upperleftx As ux, (rm).numbands As nb, (rbm).*
FROM (
SELECT
rid,
    ST_MetaData(rast) As rm,
ST_BandMetaData(rast,1) As rbm
FROM ear_agri) as r;


Can I go to a specific view if my apps icon has a badge on it (from push)?

Question: I have push notifications setup.  I have the icons badge increment for every push, then disappear when the user taps the icon.  Is there a way I can know whether that badge is showing or not when the user taps the icon?  I want to go to a specific view if the badge is showing.
Comment: http://stackoverflow.com/questions/11996683/how-to-check-for-a-badge-number-on-app-launch-on-iphone
Answer: I think you'll need to keep track of it yourself in the app. Your delegate's application:didFinishLaunchingWithOptions: will be called upon the notification and the user presses the action button and it receives the notification payload.
If you app is running in the foreground, the delegates application:didReceiveRemoteNotification: will be called. In this case you could have an integer value and increment it to keep track of the number of notifications you have. It also receives the notification payload
Reference: http://developer.apple.com/library/ios/#documentation/NetworkingInternet/Conceptual/RemoteNotificationsPG/IPhoneOSClientImp/IPhoneOSClientImp.html#//apple_ref/doc/uid/TP40008194-CH103-SW1


How do I prevent two OSes from clobbering grub files?

Question: I want to install Linux and OpenSolaris on the same hard disk in different partitions.  I'm worried because OpenSolaris seems to actively manage the grub data when updating the OS (part of the "boot environment" feature).  Is there anything I should prepare for to prevent my grub data from getting clobbered.  If I later want to add another version of linux to the  same system, what are the considerations?  Should I choose one OS and always do grub updates from that one OS?  If so, then how do I use the installation iso for a new version of Linux?  Won't it go ahead and modify the grub data on its own?  Once I've already booted into Linux, and I want to udpate my grub files, should I run a grub command that reads the data from the boot section of the drive, and puts it into the local filesystem I'm currently booted into?
Comment: This is more of an IT question, and not appropriate for SO. It's a good question but belongs elsewhere.
Comment: Reopened. In a development environment, a programmer might be running both of these Operating Systems (or two similar OSes) and run across this problem, which would prevent booting and therefore stop development.
Comment: Programmers need to eat and sleep, but that doesn't make those acceptable topics on SO.  Just because it affects programmers doesn't make it programming-related.
Comment: Eating and sleeping aren't technical. This is a valid, technical question that helps a programmer get his/her job done. I think it's just as acceptable as finding the right chair, tools for time tracking, and that kind of thing.
Comment: I wanted to defend swilliams's reasoning.  I am not sure if this is a question suitable for SO or not, it is in what I perceive to be a gray area (until the FAQs clarify further or the community votes).
Comment: It's a pretty thin line in this case, so I'll acquiesce to Thomas Owens decision, though I agree with you, ephemient.
Comment: http://stackoverflow.com/questions/42962/system-administration-questions-yes-or-no
Comment: I think this question is much more appropriate than some of the highest rated and most viewed questions (such as: "Whats your favorite programmer cartoon?"). Since this questioner is actually seeking help, it seems wrong to penalize them.
Comment: Not a programming-specific question.
Answer: You're going to have to tell one OS or the other not to automatically clobber the GRUB boot sector.
All Linux distros that I've seen have some way to prevent their installation CD from clobbering the boot sector, but it's often in some obscure advanced option.
The majority of GRUB's configuration data is not stored in the very small boot sector, which just contains a small loader program and a pointer to where to find the rest.  The configuration data is usually stored in a regular directory in a regular partition on the drive (/boot under many Linux distros).  So unless Solaris is actually going in and monkeying with the data on the Linux partition, it's probably not a huge deal... if one OS clobbers the boot sector created by the other, you can easily recover it.
Answer: Grub is a program just like any other. There is a small section at the beginning of your hard drive (the master boot record) which points which program should be used to load operating systems. This is the thing which gets clobbered when you install a new grub. It is possible, however, to choose not to install grub with a new OS (except Windows, which should always be installed first in a multi-boot system). If you choose not to install grub, you must configure the grub of the original system to recognize the new one. In other words, you control the grub of all operating systems from one (in this case, it looks like solaris would be the best choice if it is that aggressive). From within this OS, adding other options to your grub is very easy. In /boot/grub/menu.lst you can add new options and select their order. For example, I run Ubuntu, Windows, and Gentoo to play around with. My menu.lst contains the entries:
title       Ubuntu 8.04.1, kernel 2.6.24-18-generic
root        (hd1,0)
kernel      /boot/vmlinuz-2.6.24-18-generic root=UUID=887466bc-8a0d-4408-
17a-91ec1cfd9f2a ro quiet splash vga=795
initrd      /boot/initrd.img-2.6.24-18-generic
quiet

title       Microsoft Windows XP Professional
root        (hd0,0)
savedefault
makeactive
chainloader +1

title       Gentoo Linux 2.6.25-gentoo-r7
root        (hd0,1)
kernel      /boot/kernel-2.6.25-gentoo-r7 root=/dev/hdb2

Each of these contains basic information about the system I want to load, including name, hard drive location (disk and partition) and where on that disk the thing to load is. Notice, since Windows wants to load itself, we let grub know that its going to chainload by finding the Windows bootloader on disk 0 partition 0 (right at the beginning), and running that instead. For a linux system, you really only need the name, root drive, and kernel location to add a new on to your grub menu.
If you later install a linux, and do forget to skip grub installation, you can also copy the menu.lst from one to another.
Answer: I think you're better of running one of the OS's as a Virtual Machine.
With a modern CPU that supports VM extensions and a couple of GB RAM, you can run 3-4 machines easily. Use the following snippet to check if your CPU supports them.
egrep '^flags.*(vmx|svm)' /proc/cpuinfo

There are plenty of options for this: Xen, kvm, VirtualBox, VMware.
Answer: The last time I set up a dual boot system (before the days of virtual machines as in the previous person's answer), it used to give you the option of making a boot floppy.  This was useful, because then after you installed another OS and it wrote all over the Master Boot Record, you could boot from the floppy, set up Grub to chain load the other OSes, and reinstall it on the MBR.  I don't know what the modern equivalent is, because I use VMware.
Answer: Don't share /boot between OSes, it's just more work.  The default for most modern distros is to have a single / filesystem, with /boot being just a subdirectory, but even if /boot is its own partition, it'll be fine with a separate one per OS.
Each OS will then manage its own /boot, and one of them will be the default bootable partition -- you should be able to easily configure it to chainload the other.  Grub can install its headers into only its own partition without affecting the whole disk.
Comment: The problem isn't the /boot partition, it's that a lot of installation programs put their own stuff in the Master Boot Record without respecting what's there already.
Comment: Nothing post-install should be touching the MBR without your permission, and you can easily fix up the multiple grub installs after installation.  That being said, I know Debian asks if you want to install grub to the disk or partition, and I would expect similar options in other installers.
Answer: you can try installing both WITHOUT grub, and just keep a cd containing super grub which will allow you to boot either OS.
Super Grub Disk is this utlity which once run, runs grub and you can choose your OS, fix the grub on your MBR, and others.
i think you can also create a boot disk aside from grub or lilo. i'm not sure how it's done however.


Ecliptic coordinate ranges in radians

Question: In ecliptic coordinates, what are the ranges of ecliptic longitude and latitude in radians? Do they both go from $-\pi$ to $\pi$?
Answer: It is purely a matter of convention.  Longitude and latitude are normally expressed in degrees, longitude from 0 to 360⁰ and Latitude from -90 to 90⁰.  If you express these in radians, longitude would be from 0 to $2\pi$ and latitude from $-\frac\pi2$ to $\frac\pi2$.
If you are writing software, your functions should be robust enough to accept any value out of this range, for example when calculating the position of a planet, it may be convenient to have a continuous mapping from time to longitude, this would necessitate longitudes that are greater than $2\pi$.
Answer: I agree with @JamesK's answer that it doesn't really matter.
The direction of longitude = 0 is the same in both cases, and it's really a matter of taste if you display in a plot or table 0 to $2 \pi$ or $-\pi$ to $+ \pi$ (0 to 360 degrees or -180 to plus 180 degrees).
For example in Python when I type np.arctan2(-5, 5) I get $-\pi/2$ (-90 degrees) but if I type =atan2(-5, 5) in Excel I get $+ 3\pi/2$ (270 degrees) so while they are mathematically equivalent, different calculators have different conventions.
If you want to convert between on and the other, to move zero between the center and the left side, use the modulo operation as follows:
$$\mod(-1, \ 2 \pi) = 2 \pi - 1 \approx 5.2831853$$
$$\mod(5.2831853 + \pi , \ 2 \pi) - \pi \approx 1$$

Ecliptic coordinate ranges in radians


What is the range of frequency used in TV remote?

Question: Household TV remote control use Infrared rays. Infrared rays have frequency from 300 GHz to 430 THz. What is the range of frequency used in TV remote?
Answer: The most common type of IR diode used in things like remotes emits at a wavelength of 940nm. This corresponds to a frequency of 320THz.
Note that this is the frequency of the light emitted by the diode.  The diode is pulsed on and off at about 40kHz (different manufacturers use different frequencies), and the receiver knows to only look for IR modulated at around that frequency. This is what makes it possible for the receiver to find the signal from the remote despite all the background emissions in a normal room.
The 40kHz is then turned on and off at about 1-2kHz. This on and off pattern tells the receiver which button has been pressed.
Answer: They are actually RF. Infra red can't penetrative as does microwave etc... When you lie on your remote and it changes channel you will know (unless your TV is from the 90s)


What are Ubuntu cloud images?

Question: What's the difference between Ubuntu's cloud images and Ubuntu's server images?
Comment: the answer to [`What was used to build the EC2 images and can I use it to build my own images?`](https://help.ubuntu.com/community/EC2FAQ#What_was_used_to_build_the_EC2_images_and_can_I_use_it_to_build_my_own_images.3F) provides a start to answering the server (as opposed to cloud) image case, but page linked on the wiki was last updated in 2009 https://wiki.ubuntu.com/EC2Vmbuilder
Answer: One difference between standard images and cloud images is that Ubuntu Cloud Images come with cloud-init
Comment: according to https://askubuntu.com/a/307343/457417 by one of the maintainers: '"cloud images" are pretty much vanilla Ubuntu Server installs with the cloud-init package added'
Comment: True as far as it goes, but a terribly incomplete answer. I guess if that's all you wanted, it's fine though.
Comment: I agree it's a terribly incomplete answer. It's the most I've found, but would love to hear more regarding the specific ways in which the images are different besides merely their intended uses. I would welcome more detail from the community.
Comment: Ubuntu 20.04 Server image [includes cloud-init now](https://discourse.ubuntu.com/t/cloud-init-and-the-live-server-installer/14597), so this is not only incomplete, but an outdated answer as well.
Answer: From the first link : "Ubuntu Cloud Images are pre-installed disk images that have been customized by Ubuntu engineering to run on cloud-platforms such as Amazon EC2, Openstack and LXC." So, that's what those are for.
The second link is for their normal distro. If you wanted to install Ubuntu on a physical (or virtual) machine that you are sitting in front of or otherwise have access to and good control of, you would download something from the second link and install it.
Comment: What customization is it that's been done? I have still no idea how they are actually different.
Comment: I'm surprised to hear that a regular image is not ready to go in the cloud. What would you need to change in a regular image? Are these meant only for EC2? If you wanted to run on some other cloud would you use the cloud image instead of the regular server image?
Comment: Just looking at the text files in the release directories from the first link, they're all tagged with what zone and type of instance they're made for. Take a look at this : http://cloud-images.ubuntu.com/precise/20121015/ You'll see that they are literally READY TO GO for Amazon AMI. A raw distro would not be.
Comment: Another link : https://help.ubuntu.com/community/EC2StartersGuide It doesn't detail exactly what changes have been made to the images that varies from a plain distro release, but I'm sure you can start to see what's different? Do you have any experience working on cloud infrastructure - if not, I could see why you might not immediately see what the point is.
Comment: I didn't say that the regular images wouldn't be suitable for the cloud, but the ones for Amazon are actually *already in the cloud* - you click on the link and it will instantiate an AMI for you. What are you having trouble understanding? With just a raw distro, you'd have to download the ISO, start a new blank Amazon image, and then mount or transfer that ISO over the web and start a fresh install. The "cloud images" take a lot of that work away from you.
Comment: Using a cloud image on a VM of your own is actually a valid thing to do: it's a fast way to spin up a new VM and configure it automatically (via cloud-init). [Multipass](https://multipass.run/) uses the cloud images in this way under the hood.
Answer: Ubuntu cloud images dispense installing to a (virtual) disk from the ISO
When you install a desktop ISO, it takes you through an interactive installation setup that sets things like partition sizes, username and language settings. You can see such a setup at: https://askubuntu.com/questions/884534/how-to-run-ubuntu-16-04-desktop-on-qemu/1046792#1046792
This is however too inconvenient for Cloud deployments, which require spinning up a large number of OSes, and things have to be automated. This is why the Cloud images exist.
In particular, as of 18.04 it ships a pre-installed qcow2 image that you can just boot out of the box without the installer. This image format can also be easily resized.
These images are also very useful for emulation if you just want to get Ubuntu up and running quickly, I have shown a QEMU setup at: https://askubuntu.com/questions/281763/is-there-any-prebuilt-qemu-ubuntu-image32bit-online/1081171#1081171
Comment: Cloud images also have the `cloud-init` package installed, which allows run-time configuration by providing, among other options, text files on an ISO filesystem.
Comment: The cloud images are (now) provided in formats native to popular clouds (e.g. vmdk for VMWare), and may not include packages not necessary in a virtual machine (e.g. one difference I noticed is `linux-image-virtual` vs `linux-image-generic` in a regular Server install).
Answer: Not sure that the first answer is correct.
cloud-init is the Ubuntu package that handles early initialization of a cloud instance. It is installed in the official Ubuntu live server images since the release of 18.04, Ubuntu Cloud Images and also in the official Ubuntu images available on EC2.
https://help.ubuntu.com/community/CloudInit

What are Ubuntu cloud images?


Display category title on category page, Magento 2.1

Question: Wondering how to display the name of the category on actual category pages in Magento 2?  I can get the image and everything else to show up, just no spot to have the category name in an H1 or something?
Comment: The category title displayed already with default magento2.1, then can you please  explain in detail what you are going to do
Answer: You can find the Category page title H1 tag in side this path vendor\magento\module-theme\view\frontend\templates\html\title.phtml.
Comment: What if you don't want the h1 tag, just the actual name of the category?
Answer: Page Title HTML H1 TAG Can be edited at Vendor/Magento/module-theme/view/frontend/html/title.phtml
You can override this within your theme / Module
If you just like to move the title Vendor/Magento/module-catalog/view/frontend/lauout/catalog_category_view.xml
override this to your theme/Module and
Add:


Using My-Meta-Box-Class plugin, how is 'Date' value stored?

Question: I've created some custom fields in a custom post type using the my-meta-box-class plugin
which comes with a built in 'date' type of meta box input. I'm having a hard time ordering my custom posts by date. Is the date in this plugin stored as a strtotime()? If not, how can I slightly modify the plugin to get it to do so.
Is that even necessary?
Is there an easier way to order the events in my custom post type using what is already there in the plugin?
Answer: The 'date' value of 'oderby' parameter does not sort your posts by the date specified into the metabox. It will sort the posts in context with the date when the post has been published.
If you need to sort by your date from a metabox (for custom fields) you can then use the Custom Field Parameters (http://codex.wordpress.org/Class_Reference/WP_Query#Custom_Field_Parameters)
Answer: It's not really a plugin it's more of a library/class the plugin file there is just to show off as a demo.
any why when you call the date field you can set the format to a timestamp like this:
<code>$my_meta->addDate($prefix.'date_field_id',array('name'=> 'My Date ', 'format' =>'@'));
</code>
you can see a list of valid formats here.
and even better you can define your own validation function to store regular (literal text date) as time using php's strtotime function like this:
<code>//create a class named at_Meta_Box_Validate with a method of validation
if (!class_exists('at_Meta_Box_Validate')){
    class at_Meta_Box_Validate{

        public function date_str_to_time($new){
            return strtotime($new);
        }
    }
}
</code>
and then in your addDate function call that function like this:
<code>$my_meta->addDate($prefix.'date_field_id',array('name'=> 'My Date ','validate_func' => 'date_str_to_time'));
</code>


A word for a light thud that a letter makes when dropped into the wooden mailbox

Question: What is the word for a light thud that a letter makes when dropped into a wooden mailbox?
Comment: What's wrong with "light thud"?
Answer: I found these results after doing a Google search on <code>"envelope landed with a"</code>:

thud (7)
soft thud (5)
dull thud (3)
thump (1)
soft thump (1)
schlap (1)
thwack (1)
clunk (1)
clink (1)
tap (1)

The ones I think are most appropriate for a wooden mailbox would be:

thud, thump, tap, thwack

Other candidate words might include:

knock, rap, tick

and here are some adjectives you might consider:

muffled, quiet, quick, soft, dull, muted, faint

leading to several possible combinations, such as:

soft tick, muffled tap, dull knock, faint thwack, quiet rap, quick thump, muted thud
Answer: Depends, I suppose, on what the mailbox is made of, what it's attached to, and how tightly coupled the two are.
Candidates that leap to mind include:
tok
thock
thunk
chink
ktang
thwock
Comment: Of these "thunk" has the widest currency, though it might not be light enough for your purpose.
Comment: These are not words in wide currency. I forgot to say this but it is made of wood, the mailbox.
Comment: A native speaker in this circumstance (not having exactly the right pre-existing word for a sound) will in fact invent an onomatopoeia, btw.  This is one small way that English got into the general mess it's in.
Comment: The onomatopoeia could be 'dub' the second sound of the heartbeat.
Comment: @Codeswitcher How about *plop*? It might relate to water, but I think it could apply to the sound something light dropped on a surface as well.


How can an expired SSL certificate make the server and/or client vulnerable to MITM attacks?

Question: When I see the warning on my browser about "Invalid Certificate" or "Untrusted Certificate" , I might have doubt about a MITM attack at my network. Should I have the same concern when I see that the certificate expired warning? As I know, it happens only when the server did not renew its certificate, and it only shows that the server might use old security standards. Should I worry about anything other than this?
Answer: If the certificate is expired (say, after two years), this means that a potential attacker had at least two years of time available to brute-force or otherwise attack the key. OK, this means more risk than when the cert is only a few months old, but with good keys there should still be virtually no sudden risk increase at the moment of expiry. Nevertheless, this aspect should not be discarded. (Also, old certs may have been produced in the good old days of less secure signatures)
But more importantly, when a key that is still active is compromised, this fact may be advertised by revocation (e.g., CRL or OSCP). If a key gets compromised after its expiry, this is not done (simply because it would be a waste of resources to track those cases when the certs are invalid anyway by expiry).
In fact, it may be the case that the owner did renew the certificate, but what you are looking at is a fake site created by a MITM.
So, yes, you should be sufficiently worried (and worried as hell if that is any site of importance such as a banking site or a shop) and maybe inform the owner.
Answer: Mostly it is a trust issue.
If the client trusts invalid or expired certificates and he is used to it,  what makes him distinguish between a valid expired / invalid certificate from other malicious one? Probably he will click without read yes to all questions...
Also if you are not following the rules / standard why to implement them?
To keep the traffic safe? But why your customers should trust they are safe if you do not care with standards?


Fonts appear in different color in buffer

Question: When I write a big text exceeding the window bounds when starting Emacs the fonts appear in other color than the rest. If it makes any good to mention, when I disable font-lock mode text appears in one color as it is.
Comment: This looks as if whitespace-mode is enabled...
Comment: Do you see the problem when you start Emacs using `emacs -Q` (no init file)? If so, `M-x report-emacs-bug`, providing a step-by-recipe to reproduce the problem. If not, recursively bisect your init file to find the culprit.
Answer: Run M-x customize-group RET whitespace RET to customize how whitespace-mode works. In particular, you can scroll down to the "Whitespace Style" setting, and uncheck the "Lines, only overlong part" option to turn off this particular effect. Use C-x C-s to save the settings, and then reload or revert the buffer to update it.


Can the long guard block any type of punch?

Question: So I heard that you can block punches with the long guard (especially overhands), so does that mean that you can block any type of punch with the long guard?
Answer: Obviously, no kind of guard helps against every type of punch. The long guard is particularly well-suited to limit the tactical options of an opponent, covering a lot of the possible punches. But it has its limits, especially as soon as people slip past it:

When using the long guard, you must watch out for overhand rights, hooks, and low kicks.

On the other hand, as you know these limited options, you can watch out for them.
Comment: +1 for the "limiting of options". Defensive postures aren't just for defense, but also to reduce the number of options an attacker has, meaning fewer things to think about on the defensive side. (Not that they can be *ignored*, it's all about likelihoods.)


Road bike for 6 Foot

Question: I want to buy a bike. I have a bike who may interest me, it is a Tri Bike 51cm. I was wondering if it was OK for me.
I know that for my height 53-56 cm is better but I'm only 115 pounds.
Would that be OK for me?
Comment: 56 even might be too small. My road bike is 58 and I'm 5'11".
Answer: A 51cm frame sounds too small for you, assuming you're average limb length for your height.
You can put the saddle up really high, but that makes it a more aggressive body position, and your seat post is not as well embedded in the frame.
You don't mention your age - I'm guessing you may still be growing, in which case the too-small frame will be getting smaller as you grow.
Answer Pass on this bike - there will be another.
Answer: I am 5'10" and had the use of a 53cm while I decided what to buy. This was clearly too small - had some knee discomfort and felt "bunched up" on the bike. I bought a 58cm and can most definitely feel the difference. My arm may be a little longer than normal, but I am happy with the 58. Don't settle for one that is not the right fit.
Comment: Welcome to [bicycles.se] @larry. As with all new members we recommend that you take the [tour] to make best use of the site, and since you're writing an answer see [answer] also. Good to see you here

Road bike for 6 Foot


When should I consider using TCP or UDP?

Question: I know, though not that well, the difference and pros & cons between these 2 protocols. Well, I'm still unclear about using them, specifically, which protocol I should employ when building applications on top of them? Are there universal principles or commonly-adopted practices? What factors should be taken into account when making the choice. E.g. UDP is always considered in preference to TCP for video streaming service.
Answer: TCP- when you send information there will be acknowledgement like your courier service that you received the courier . if there is no acknowledgement then resend.
UDP-no acknowledgement. no resend.
First you should know sensitivity of information you are sending and receiving . for example if you are dealing with some money transfer you certainly need the acknowledgement that bank received your money, if there is problem in connection you come to know that the packet are lost and you should retransfer your money. (use TCP)
second when in real time communication like VOIP and video streaming if the packets are lost there is no sense in retransmitting them because the time has passed . for example you are speaking with someone over voip and you receive "hello" lost packet in between your communication you feel annoyed and same applies to video streaming.
I hope this helps.


Can I hardcode an enode hex-section in a local network?

Question: I have multiple devices with unique IP's. Is there a way to attribute the same enode hex to all of them (while still having unique IP's contained in the enode).
Answer: TL;DR: no.
The hex part of the enode address is the public key of the node. It's the one generated from the node's private key. Having the same public key would mean having the same private key on all your nodes which would not work as they would be considered as the same node and conflicts would happen. Your private keys have to be specific for each node.
Comment: I am using 20 Raspberry Pi zeros installed on mobile robots. I'm using geth to run PoA clique, but also going to experiment with PoW.
Comment: According to your answer: If I want to connect two peers/nodes, the minimum amount of bytes for are required to exchange is the enode.

The enode can be up to 169B, which is more than the payload of my communication module. Is there a way to reduce public key length?
Comment: @AlexPacheco I'm not sure to understand what you want to do. What do you mean by restrictions of your communication module? Don't you use a regular computer?
Comment: And no I don't think you can reduce pub key length if you want to be compatible with existing network. However you can modify a client of you choice and create your own version of Ethereum with smaller keys but it won't be able to peer with regular nodes.
Comment: In the flair and in the tittle I mention private/local network. They are not supposed to peer with any node outside this local network.

My nodes perform a greeting triggered by a certain event. When this occurs, they add each other as peers for a defined amount of time. However, before greeting, they have no memory/dont know each other. So they need to send the enode. Bandwith of this communication interface is just a few bytes via I2C, hence sending a full mainnet ethereum enode wont be possible.

Option 1) Reduce pub key size
Option 2) Store pub keys in each nodes memory
Comment: @AlexPacheco interesting, so yes I guess you could hack the P2P protocol to reduce key size but I'm not sure about how secure it's going to be. Just curious, what kind of device do you run and what client do you use?
Comment: @AlexPacheco awesome. I hope you will succeed in hacking this.


Quickly change the font size in Terminal

Question: I'm looking for a way to perhaps type a command and have the font change by increments of say 5 or 10. Right now Cmd-+ is taking too long if I want to go from a small font to a large font. I'm using Neovim through Terminal. Is there a way to do this? Vim plugins don't seem to work. Perhaps a terminal emulator?
Answer: Why not open terminal preferences and choose to change the defaults. You can then open a new tab at the exact size and color you prefer?
That and using screen or tmux means you can have your environment run regardless of which window you place it in. The zoom increments are better for temporary small adjustments as you so correctly have pointed out.


Heap dumps and memory use discrepancies in android?

Question: Alright, I am not typically one to ask for help as I usually prefer to find answers on my own, but unfortunately I seem unable to do that.
I am messing around with live wallpapers for android 2.1+  Things went pretty well until a ways in I started getting a OOM error:
<code>Java.lang.OutOfMemoryError: bitmap size exceeds VM budget
</code>
Ok - I did my research and found out that I surely have a memory leak somewhere.  So I read up on how to analyze such problems, opened up the DDMS and did a Heap dump.  the Heap size usually runs around 4.5-5mb in size and never more than 60% full.  This didn't make sense, because I checked the running services on my development phone, and it reported my process as using anywhere from 35-42mb of memory.
I'm not asking for anyone to find my Leak as that would require lots of code etc. Just to explain how to properly analyze my memory usage, since I seem to be utterly dumbfounded as to what is going on.
Answer: Thanks satur9nine, I actually did some more digging after posting this and finally got a grasp of what was going on (of course that was after I posted the question, go figure).
I discovered that the memory usage reported in the services manager in android is referred to as the Native Heap. This is the Heap size + bitmaps (among other things possibly?).  But I was still a bit confused as to why it was 40+ MB at times, when the images I were loading were only ~900 KB.  When it clicked that images no longer stay compressed when loaded in to memory.
So my loading of approximately 30 small PNG's was taking up a massive amount of memory.
I was cycling through each of these PNG's to make a Rain animation.  I didn't realize at the time that was a bad strategy.  Once I realized that was the problem, I scrapped it and Wrote myself a simple little "Particle System" To generate a nice rain animation with just one particle icon loaded in to memory!
Comment: Glad you solved your problem. I'm not surprised it wasn't really a leak. Usually you have to try hard to leak memory in Java.
Answer: I'm guessing you already did this, but just in case... did you examine the line that triggered the OutOfMemoryError? How big is the bitmap you are trying to create?
If it is a leak here is an article that might help you analyze a heap dump (you won't have to use eclipse despite the article title):
Android ==> Memory Analysing ==> Eclipse memory analyzer?
Good Luck.


Soul Cairn: Constant Health Drain

Question: I've been training restoration just outside the Soul Cairn portal inside the Volikhar Balcony and I reloaded my save to continue training and now my character is experiencing constant health depletion. (Keep in mind my character is now a werewolf, meaning I can't enter the Soul Cairn.) I've researched this problem and I'm aware that this is a glitch. Is there a known solution to solve this problem other than reloading a previous save?
Comment: No, I'm playing on xbox 360. @desaivv
Answer: What were you before you were being injured?

If you're a vampire, you're fine to go through normally.
If you allow your soul to be partially put away in a soul gem, you're also
fine, (from quest).

But once you become a human or a werewolf, you have your soul back.
Now this place feeds on souls, so its feeding off your life essence, thus taking your life away.
The only thing you can do is take many potions with you, many magika and health potions so you can use health restore magic too.  I had to go back in as a human and it was taking my life away, I used many potions and magic to get through without dying.
Comment: I completed the storyline as a Vampire Lord initially, I then decided to become a Werewolf. There wasn't anything I could do other than reloading a previous save.
Comment: yeah its a huge bummer, i too became human and tried going there but i had constant health drain, i endured it with magic and potions,
Answer: I know this is old, but I'll respond with what worked for me so that others can find it.
I was in the Soul Cairn as a vampire lord and randomly started taking constant health drain without any negative magic effects listed. The effect continued outside of the Soul Cairn as well. I tried a bunch of stuff and all that worked was making a mad dash for Solitude and praying at one of the shrines (I used the shrine of Kynareth, not sure if that matters). I happened to have a ton of potions and modded food and skooma stored up in my inventory which kept me going until I could make it.

Soul Cairn: Constant Health Drain


Make Ubuntu first option when dual booting

Question: I have Windows 7 and Ubuntu installed. When rebooting I always have to choose between those 2.How can i make Ubuntu become the first option when i boot my computer?
Comment: What **Ubuntu** version?  For 12.04, this should already be the default behavior. Do you want the choice, or delay to be removed also?
Answer: Just press Ctrl+Alt+T on your keyboard to open Terminal. When it opens, run the command below.
gksu gedit /etc/default/grub

Find this line:
GRUB_DEFAULT=0

0 is now set for Windows 7, change it to the number associated with Ubuntu
Another way is to use Grub Customizer.  If you don't have it you can install it:
sudo add-apt-repository ppa:danielrichter2007/grub-customizer
sudo apt-get update
sudo apt-get install grub-customizer

Answer: Open your terminal and type this
sudo gedit /boot/grub/grub.cfg

then find this line (mostly line Number 13)
set default="0"

in set default if you place 0 it will boot to First title you have in grub.cfg and for 1 its boot to 2nd title .
so for your case it should be 0.
Answer: Whereas the use of EasyBCD to edit the Windows boot loader, may well be a feasible answer when the  traditional BIOS and MBR approach to starting up your PC is in use. When the computer in use has been shipped with UFEI firmware and boot manger, as is increasingly the case, then using EasyBCD is (by their own admission) not really appropriate.
One of the alternatives offered (by EasyBCD) is to use a virtual machine. That taken together with another alternative given, which involves Grub2 EFI wresting control from MS UEFI, booting Linux first and ultimately chainloading NTLDR to boot into windows, I'm inclined to get overwhelmed by the unnecessary complexity of it all and say "how do I now make this computer entirely Ubuntu".
Answer: For what you are asking (Windows for the Default), I'll assume that you are using Wubi.
To edit the Windows Bootloader, install EasyBCD.  It is a free tool (you'll have to click the "Register" Link at the bottom, although you don't need to register) that allows you to modify the Windows BootLoader in a pain-free way.
Next, launch EasyBCD.  Then go to the Edit Boot Menu part, click on the Yes tickbox beside Ubuntu, then click on Save Settings.  You are Done!


JQuery-ui 1.8.2 draggable malfunctioning in Internet Explorer

Question: I'm maintaining a jquery/php filearchive for the company I work at.
One of the features is the ability to drag files into folders. This functionality works wonders in both Chrome and FireFox but exhibits peculiar behaviour in Internet Explorer.
What happens is that when a drag is initiated on an item a selection rectangle is created. The intended item is dragged along, and removed from its initial position, so in that regard the plugin is working. The problem is that all the other files receive select events when the selection box passes over them, not only is this not intended, it is also ugly.
I have tried to include all the relevant code here:
Edit: I tried also including the css as a pastebin, but as the noob I am in here, I was only allowed to make one link
js
The versions used of jquery and jquery-ui is 1.4.4 and 1.8.2 respectively
The file divs are made draggable at line 919 in the js file.
I have googled quite a bit and also looked at the jquery demo pages, where the draggable interface works as intended, also in Internet Explorer.
I hope someone will be able to help me escape from this frustrating pit of cross-browser compatibility hell by means of showing me the way of my mistakes.
Request more information as needed, I will try to provide it in a timely manner.
Best regards,
Johan Abildskov
Comment: IE is broken...what else is new? :)
Comment: While I do apreciate your wit, and quite agree with the statement, I was hoping for something a bit more hands-on to help me with my issue :)
Answer: The issue was actually resolved when I removed draggable from some of the items also being draggable.
Seems draggable and droppable actually conflicted abit in the way we used it.


Does deleting Clash of Clans also remove my base from the world to prevent attacks?

Question: I deleted clash of clans for a break. I will re-connect with Supercell ID when I feel like returning. However, will this prevent people from attacking my base? I thought that when I delete the game it erases my base from the system so it can't be attacked. Is this true?
Answer: Firstly, the system doesn't know if you've deleted the app from your phone. The only thing it keeps track of is your user ID (or your Supercell ID), and the base(s) attached to it. So if you have not deactivated your account, your base will remain.
Secondly, if you had the intention of starting over to begin with (which is what I take from your statement of "I delete the game it erases my base from the system"), then having your base remain at it's current level, even if it does get raided repeatedly, it is ultimately more productive, no?
Unless you deactivate your account, your base will remain in the system, and it will be raided whenever it is available.
Answer: Short answer, no. Long answer, your base is stored in the clash of clans database which is online. Not your phone/tablet/iPad etc. Also, your base can still be attacked by others. But, there can be a rare occasion where your base might get lost (this happened to one of my friends). In that case, you will need to sign in with Game Center, sign into supercell ID, and if those don't work, contact support.


Is the Radio Room necessary?

Question: Given that the rate of new dwellers via pregnancy vs radio room is staggeringly in favor of pregnancy, why is the radio room even necessary considering the risk (raider/deathclaw attacks) vs reward is completely unbalanced?
Comment: I think there are a few components to this question. (1) What purpose does the Radio Room serve? (2) Does the Radio Room significantly increase the chance for a deathclaw attack? Neither of these are directly addressed by the linked question, IMO.
Comment: [related question... maybe even duplicate](http://gaming.stackexchange.com/questions/232904/how-am-i-supposed-to-use-the-radio-room)
Comment: Can you clarify on the risk. As far as I know the only downside to a radio room is power consumption. I haven't seen anything that suggests it increases the chances of raider or deathclaw attacks...
Comment: I only know about the risk due to the game tips that display while the vault is loading.
Answer: A well-staffed radio room helps boost the happiness of the population. Even if you're ignoring the newcomers it attracts (which I'm currently doing) it's useful if you have the power and guns to keep your fortress running.
While it is much faster to carry out breeding en-masse, the radio room is nice if you're just stopping in to collect resources and SPECIAL training, since you don't have to micro-manage your population, and you don't have to wait for newcomers to grow up before assigning them to a room.
Deathclaws aren't that big a deal if you have a reasonably large, armed population. They don't stay in one room long enough to kill a dweller (the first time they go through your vault), so as long as you can kill them before they reach the end and start looping back you'll be fine. The only remaining danger is that incidents will occur while your dwellers are still on low health.
I have a 6-person room just by the door, and nobody in the double storage rooms/living quarters on the top couple of floors. This means that any invaders will only encounter 6 dwellers at a time for the first 4 or 5 rooms. These rooms have priority (after my wasteland wanderers) for good weapons. Raiders don't make it past my first room (6 dwellers in a Nuka Cola Bottler with enhanced sawed-off shotguns), and deathclaws don't make it past my 4th inhabited room.
Because of these security measures, I keep my radio room fully staffed and I'm currently sitting at around 93-94% happiness.
Comment: Note: Deathclaws *can* kill full HP dwellers - but only low-level, low endurance dwellers. I believe that as soon as they hit level 5 they won't die with basic stats, but radio rooms don't give dwellers exp, so you'd want to train them up somewhere else before putting a fresher in a deathclaw-vulnerable radio room or living quarters.

Is the Radio Room necessary?


C# Automatic deployment/execution from a usb device

Question: is there any way that a process on my usb will be launched automatically when the usb is connected to the computer?
Is there any way to deploy a file automatically from the usb, each time the usb is connected to the computer?
thanks.
Answer: The user would have to have "auto-play" enabled and then you can setup an autorun file to accomplish this, but it is highly dependent on the users configuration.
It should be noted that this is also a huge security concern for many people. Auto-run usb sticks are one of the ways that malware is automatically distributed.
Not trying to tell you your requirements, but I would consider if there is a better way to do this.
Answer: Take a look at Autorun.
I have an old mobile-phone that emulates a cd-drive with a autorun.inf on it. That autorun started an app that let me manage my mobile (calendar, callist, sms) from the computer.
This probably only works if the user has Autorun enabled. It's the first thing I disable.


Does reaching the global optima guarantee good performance in a task?

Question: It is to my understanding that, in deep learning, we are essentially trying to minimize the loss function that we have defined and reach its global optima through some form of optimization technique. However, with AI being applied to so many fields, can we be sure that there exists a loss function for every task, such that upon reaching its global optima, it guarantees reasonably good/human-level performance in the task?
Answer: There is an existence of a loss/reward function for any task that can be evaluated, but this does not mean that function generalizes to any model.
In your prompt you mention "human-level performance", this assumes a metric such as accuracy, auc, precision, winning %, etc that humans were evaluated on for some task. Since it is possible to model any function with a boundless resource budget we can then model a function that reaches any form of theoretical optimum for that metric and some given domain.
Ofcourse there is issues with what I wrote above in an applicable sense:

Infinite resource budget doesn't exist.
Not all metrics can be easily calculated.
We usually subset a domain to "train", but to find one that truly encompasses a domain is usually not feasible and requires clever data usage and handling.

So in practice we make simplifying assumptions that handle the above issues. Examples include finite-parameter deep learning models designed for efficient learning, differential metrics such as distance, and data augmentation. In doing so, it is possible to achieve cases where the global min/max over its parameter space performs poorly. Its the researcher/engineers job though to make this not the case.
Comment: Thank you for your answer. I would like to clarify on a few points:

1. `this does not mean that function generalizes to any model` - Do you mean that not all models may be suited for this function?

2. `possible to model any function` - Can everything be expressed as a function?

To give an example, I'm working on a navigation task, the network is learning a function that maps from image to action, but can we be sure that such a function exist, one that generates the correct action for all images?
Comment: adding to it outliers would be hard to determine as you club number of task together  which could affect all your performance metrics
Answer: As a more direct answer to your question as stated in the question title, finding a global minimum means we have found the optimal solution for that model.  This doesn't mean that the model necessarily works particularly well.  Hence the saying from George Box, "All models are wrong, some models are useful."
In other words, while you may have found an optimal state for that model, the model may not be optimal or even acceptable for the task.  (Note that that phrase can be interpreted in different ways, and this is not the only way to apply it.)


Hollywood Principal: I dont understand it

Question: Ive recently switched up to Enterprise Library 5 and Unity. I was quite happy with the examples that were provided until I surfed around and started reading the hiss about "Service Locator is an Anti Pattern". From there I stumbled into writings on Composite Root and the Hollywood Principal of "dont call us, we'll call you".
I think I understand the benefits of Composite Root but I dont understand how we can avoid calling it in order to get instances of the classes the application needs. So I think I might be misusderstanding the whole idea.
Im approaching this as a new way to do a centralised factory pattern. But at some point I still have to call into the Factory Pattern to get my instances? So for the code below from what Ive read the Unity Container should be created somewhere near the root of the app (not in a form). That in turn should take care of my DI for exception handling and logging. (Note this is just 2 min play code so it's meant to be pointless)
<code> public partial class Form1 : Form
    {
        public IUnityContainer Container { get; protected set; }

        public Form1()
        {
            InitializeComponent();
        }

        protected override void OnLoad(EventArgs e)
        {
            base.OnLoad(e);
            this.Container = new UnityContainer().AddNewExtension<EnterpriseLibraryCoreExtension>();
            try
            {
                throw new NullReferenceException("Mucking around.");
            }
            catch (Exception ex)
            {
                    TaxCalculator calc = this.Container.Resolve<TaxCalculator>(new ParameterOverride("fire", 888));
                    calc.LogWriter.Write(calc.Fire, "muckaround");
            }
        }

public class TaxCalculator
{
    private ExceptionManager _exceptionManager;
    public LogWriter LogWriter { get; protected set; }

    public string Fire { get; set; }

    public TaxCalculator(ExceptionManager em, LogWriter lw, int fire)
    {
        this._exceptionManager = em;
        this.LogWriter = lw;
        this.Fire = fire.ToString();
    }
}
</code>
Trouble is, if I cant call a TaxCalculatorFactory which in turn calls the container, or just call the container itself, how do I get a specific type of Tax Calculator?
How/ where do I get my instances from? Do I start the app, build a bunch of factories that I may or may not need during the apps lifetime and then have the various layers of the app request instances from the factories? Seems like I'd be passing around alot of factory references so Im not sure what the benefit is? Or do I initialise static classes in the container and just call them?
As you can see Im in a muddle re: the idea of Hollywood Principal.
Answer: One alternative to a Service Locator is to use an IoC container that can inject dependencies during object creation.
This SO question asks a similar question, which points to this Autofac article on object reference types. It should give you some ideas about how an IoC container can address this issue.


What does 星辰大海 mean?

Question: As far as I know, 星辰is used to mean time, and even when used literally, it has nothing to do with 大海, or it makes no sense, especially when put in the context of 我们的目标是星辰大海, which could be heard in mainstream media like Radio China.
So what does it really mean?
Comment: If you just figuring the connection, imaging travel in the middle of the ocean like "Life Of Pi", all you can see is stars and ocean. As the answer descibres below, it is originated from a Japanese scientific novel, to indicate an ambitious target.
Answer: 星辰 means stars, Milky Way. 大海 is great ocean.
Both are huge, boundless.
It's used to decribe we have a very ambitious target.
Answer: 辰 - 清早(dawn). It also means collectively the star, moon, and sun (日月星辰).
星辰 - (Countless) stars in the early morning sky. It is interpreted through 會意 (huìyì) - largeness (浩瀚星辰). Also, "largeness" is a characteristic of 大海 (大海無邊).
So, the sentence "我们的目标是星辰大海" means "Our goal is so deep and large like the universe and oceans that have no limits". In another similar way: "我们的目标是(深)遠(鉅)大無邊的的", a suggestive slogan.
Answer: 无边无际 像星河一样,一般形容人和宽广的胸襟,或者是因为某件事情体会到自己的渺小
Answer: As far as I know the phase could have older historical background written by a dude known as Heinrich Heine, but it was popularised more so by a Japanese anime known as Legend of the Galactic Heroes (It is basically a Japanese rendition of the Chinese classic 'Three kingdoms', but in space, nonetheless it is something that is bingeworth imo).
The phase is often used to describe someone or a group of people with 'serious' ambitions.
Or people just uses it for memes as a references at times.

What does 星辰大海 mean?


Formatting APA Style Headings for HTML in Online Publications

Question: I do not see any questions here about how to convert APA (or MLA, Chicago, Turabian, etc.) style into HTML (edit: styled with CSS) for online publication. Since HTML is perhaps the most accessible format for assistive technologies, I'm puzzled. As a professional who helped faculty create and teach online courses, I have experience with both website design and academia. One problem I've wrestled with has been APA run-in headings (level 4 primarily). I finally submitted the problem to Stack Overflow, and a CSS (cascading stylesheet) guru wrote a brilliant solution. My primary question is this: has anyone here encountered this problem? I'm also wondering, is the crossover between academia and online technology insufficient to know this is a problem? Is anyone here aware of issues in converting academic writing into accessible web-based material? Has anyone asked a webmaster to convert a paper into a web document and been told it was too difficult?
Answer: No, have not encountered this problem: some publishers do aim for an online presentation of materials using regular web pages indeed, but then they have a freedom to pick a convenient citation style and whatnot. And if you are not a publisher, the "normal" way to disseminate the research results in academia is a publication list on a personal page and PDF files. So in a nutshell, there is not enough interest to the specific problem you are posing here indeed.
Comment: Thanks! I recall a similar preference when working with faculty who were creating online courses. We encouraged faculty to convert as much material as possible into a true online format for accessibility, but in some courses that task was just too overwhelming.
Answer: APA and other conventional scientific writing style guides are not well-suited for online publications.
The most elaborate way of displaying scholarly articles for online viewing is probably the one used by Research Ideas & Outcomes at Pensoft Publishers.
Here is an example of a recent paper, including a machine-readable XML-version of the paper.
Browsing through the XML, you will see how standardized it is and how many metadata it embeds -- here is a screenshot of one part of the
-tag (containing information about the submission history, license, abstract, keywords, figure counts etc.):

Such a metadata-rich formatting allows them to track statistics such as which Figures were viewed or downloaded most often - - again an example from the paper above:

EDIT: Just found out about DocMaps, this might be relevant here too: https://docmaps.knowledgefutures.org/
Comment: Yes, XML seems to be a superior format if the publication uses XML. Are academic publications not published enough on HTML websites for this to be an issue? That would explain why HTML formatting and APA style don't seem to intersect.
Comment: I should have clarified in my comment above that while XML may be superior to HTML for screen readers, it does not **style** the appearance of content on a webpage. That has to be done with CSS — the same method used for HTML. So the issue of how to style run-in headings also applies to XML websites.


How to disable transparency when a window is highlighted?

Question: I'm using KDE 5.5.5 and have enabled highlighting windows in task manager settings. The problem is, I have a lot of windows open and when highlighting some windows they are barely readable under a stack of transparent windows. How can I turn off transparency when a window is highlighted (so that the highlighted window is simply shown on the top)?
Answer: Try this and see if it helps (there are an huge number of options and it can be a bit overwhelming).
Go to Applications -> Settings -> System Settings
Under Workspace click the Desktop Behaviour icon now click the Desktop Effects icon
Scroll down to Translucency and click the square config icon for loads of options
Comment: Unfortunately no option in translucency changes the behaviour of task manager's highlight. Even disabling translucency doesn't help.


Why do flax eggs make my bread mushy?

Question: I've been trying to bake bread using homemade flax eggs, but every time I do, the inside of the bread is mushy and uncooked. What am I doing incorrectly?
Comment: Some good information on egg replacers here: https://cooking.stackexchange.com/questions/20830/egg-replacer-for-bread-dough

In my own vegan/gluten-free bread baking, I swear by Bob's Red Mill egg replacement.
Comment: what kind of bread are you making that requires an egg substitute? Can you elaborate on your method please?
Comment: Neither of them required it. I only wanted to experiment. The first attempt was with paleo sandwich bread recipe and the other was with 90s low carb keto bread. https://gimmedelicious.com/90-second-keto-bread/ | https://www.paleorunningmomma.com/paleo-sandwich-bread/
Comment: I am unwilling to answer but I would suggest that the problem is that you are adding water to the recipe in the form of the flax eggs. The flax will retain the water and that will increase the cooking time or make it too difficult to cook the bread evenly. Can you manage to add less water? Also, flax may not be the best substitute for the eggs in these recipes (both of them do call for eggs). I would suggest trying dried gluten flour but both of these recipes are strenuously wheat-avoiding haha
Comment: Thank you for your efforts.
Answer: It may be that eggs serve a different purpose in the recipes you experimented with.
Eggs can be either a leavening agent, emulsifier, thickener, binder, coat and sealer, or  color and shine.  (source)
From the recipes you posted, it looks like one was more of a leavening need (90 second recipe) and the other was more for moistness (sandwich bread recipe).
Gluten free bread calls for eggs because...

Eggs are natural leaveners that help boost the rise and volume of bread. Eggs also add moisture, flavor, and protein to gluten-free bread recipes. If you select a gluten-free bread recipe that includes eggs, you have a better chance that the resulting bread will have good color, more volume, and softer texture. Eggs also help to extend the shelf-life of gluten-free bread, which can become stale more quickly than wheat bread.
https://www.thespruceeats.com/tips-for-better-gluten-free-bread-1451069

Flax eggs appear to be best used for binding because they don't offer much structural support (source).

Why do flax eggs make my bread mushy?


Keeping video settings in CS:GO

Question: Everytime I decreased my visual setting it maximizes the whole settings at every restarts. I dont know if I used a console command unintentionally. How can I solve this?
Comment: Did you add extra stuff,  like autoconfigs or mods?
Comment: @Retrosaur thanks.was using a different hud. write this as an answer so I can accept
Answer: Installing CSGO with custom HUDs will preload the conditions of the hud everytime you run the game.  Some HUDs are more demanding than others, and will amp up your graphics everytime you run it, while some are less demanding.
Just uninstall your HUD, and you should be fine. If you don't know how to uninstall your HUD, an easier fix is to go to the Game Properties option by right-clicking the game in Steam, then click Validate Game Files.  This will check for discrepancies in your game client and the actual game, and reset your settings accordingly.
Answer:
Change your CS:GO video settings in-game according to your preference.
Alt+TAB to Windows.
Go to C:\YourSteamFolderHere\userdata\765****\730\local\cfg in File Explorer.
Right-click "video.txt" and select Properties from the bottom of the menu.
Above the OK-button, select Read-only, then press OK.

Voilà, your video settings won't reset anymore.
To change your settings again, you have to uncheck Read-only before you change them, then put it on again.. Marking "video.txt" 'Read-only' means that the game nor you cannot write to the file.
Comment: I don't know why this is not the accepted answer but great! Works perfectly!

Keeping video settings in CS:GO


Can't install usermin or virtualmin: "Expecting form-data encoding, but got normal encoding"

Question: This is a fresh server, with webmin freshly installed-- in fact, installing usermin is the first action I'm (trying to) take with it. I'm logged in with a user that has sudo privileges, however I've also tried it as root.
I select Usermin from the list of unused modules, then "Install Usermin tar.gz package". This brings me to an error screen that says "Expecting form-data encoding, but got normal encoding".
The lack of help I've been able to find for this is disheartening. Either no one uses Usermin, or no one has ever had this error. In fact, "usermin" isn't even an existing tag here.

Trying to install virtualmin gives a different error: Failed to install module from http://download.webmin.com/download/virtualmin/webmin-virtual-server_5.04.gpl_all.deb : Not a valid module file : tar: This does not look like a tar archive tar: Skipping to next header tar: Exiting with failure status due to previous errors.
To arrive at that I followed the install instructions: Go to Webmin Configuration-> Webmin Modules-> Install from ftp or http URL.

Neither usermin or virtualmin are critical for me. I've never used them before, but I'm setting up a new server today, and thought a graphical UI might make my life a little easier. Webmin itself installed just fine.
Answer: Bug -- a fix is expected soon:
https://sourceforge.net/p/webadmin/usermin-bugs/455/?limit=25