Recently, (on meta), I was able to answer  30 seconds after it was closed.  Close time:  2013-12-05 02:37:22Z Answered at: 2013-12-05 02:37:52Z   This is fine. It is not a bug, rather it is  as pointed out .  While answering the question, there seems to be an interval in which (web sockets?) check if a question has been closed or not. If the check returns true, you are presented with the following message:          After closing some questions, I found that the interval seems to be under 1 minute. (I got ~22 seconds, ~49 seconds, and ~13 seconds when testing)  In other words, if you are typing an answer to a question, you have less than a minute to submit your answer - assuming the question has been closed. You will then be presented with the message above and the submit button will now be disabled.  &lt;input id="submit-button" type="submit" disabled="disabled"&gt;         There are no evident problems with this. It seems to work well; however, if you edit the HTML and remove the disabled="disabled" attribute, you can bypass this and submit an answer.  Here is  on SO where I did this. (10k users only - I deleted my answer)  Close time:  2013-12-05 19:11:28Z Answered at: 2013-12-05 19:41:06Z   By removing the disabled attribute, I was able to submit an answer ~30 minutes after the question was closed.  Should this be allowed or not?  from Jan 2011, Jeff points out:     the grace period for answer submission is now 4 [hours] after after question closure   Yes, the quote does say after twice.  Despite the fact that this comment was written ~3 years ago, there is still a 4 hour grace period in place. After sitting on a particular answer for ~5 hours, I failed to submit an answer and was presented with the following:        This grace period is intended for people already answering a question before it has been closed. So why is the submit button immediately disabled upon being notified that the question has been closed? This defeats the entire purpose of a grace period. Especially since it can be bypassed.
Question:   Answer:   The question was closed at 11:57:57 (according to the hover-over-"x-mins-ago" bar) and the answer was posted at 12:16:35. It's a fairly lengthy answer, so it's possible that it was started to be written before it was closed but I swear I've started to answer a question then I got a banner along the top saying "this question has been closed" and the answer was no longer post-able.
Pytest is in PATH but not found Why is it possible to conclude everything from a false statement? Possible Duplicates:             I heard a professor of mathematics explaining that the following conslusions are true.   $\textrm{False}\Rightarrow \textrm{True}$ $\textrm{False}\Rightarrow \textrm{False}$   Could someone please explain to me why both conclusions are true? I am especially interested in the first case. I'd like to hear two explanations if possible: One for mathematicians and one for non-mathematicians. :-) How do you call an external command (as if I'd typed it at the Unix shell or Windows command prompt) from within a Python script? Poisson / exponential distribution Next weekend you will be participating in 12km cross country race on a mountain.The average time between  two successive wild animal sightings on the mountain is reported to be 5 minutes  (a) What is the probability that you see at least one wild animal in the 11th minute of the     race given that you will see 3 wild animals since the start of the race?  (b) What is the probability that it will take more than a quarter of a hour before you see a wild animal after ten minutes of running?  Now I have attempted (a) , but I don't know whether my thinking is correct. (b) on the other hand makes little sense to me.  My attempt:  (a)$ X~ Poisson(\frac{1}{5})$ and $Y~Exponential(\frac{1}{5})$  $Pr(X&gt;4) = Pr(X&gt;1)$  (I am thinking that this is some variation of the memoryless property)  $Pr(X&gt;1) =Pr(Y&lt;1)$  $Pr(Y&lt;1)= 1 - (e^{(\frac{-1}{5})})$  Perhaps, I was a bit to vague in my attempt of (a). So here goes my attempt of(b).From my understanding of the question , it is asking what it the probability that the time between events(in this case animal sightings) is more than 25 minutes given you have been running for ten minutes  Now from what I know the fact that you have been running ten minutes is irrelevant this is due to memory-less property of the exponential  distribution   so without further ado  I present my attempt at (b)   let $X $ be exponentially distributed random variable with $\lambda = 1/5$  then  $Pr(X &gt;15) = 1 - Pr(X &lt;= 15)$ What are 'return' pins? On a VGA connector, there are numerous 'ground' pins. Three of these are Red return, Green return and Blue return; But why does each color component have its own ground pin? Merging two files, one column at a time How to Logout of an Application Where I Used OAuth2 To Login With Google? Setting page numbering on Word I have a word document. The first four pages are title and index. After that, the “Chapter 1” starts. I want page numbers to begin from the “Chapter 1” onwards only. The first 4 pages should not have any page number.  How do I achieve this? What is "function*" in JavaScript? Why does my DIY "solar panel circuit" show battery voltage and not solar panel voltage? Are there any drawbacks to using a wish spell to increase ability scores? If not then what would stop players from just using wish repeatedly and raising their ability scores to 30?  I'm just getting back into RPGs with D&amp;D 5e after not playing for years, and I seem to remember this being covered in the editions we played back then. With the following circuits as examples :    and    How will the current I know how much to flow? Would any other wave travel first in the circuit and then come back and say so much current should flow? How to backup settings and list of installed packages If I want to make a backup of everything I have done since the fresh install of Ubuntu, what are the possible options? What all should I backup? I want to get all the settings that I changed, all the packages I installed, etc. new array.sty and colortbl.sty incompatibility? I just upgraded my texlive distribution and can no longer insert space in table rows using \\[x pt] syntax when colortbl is loaded.  It seems that recent changes to array.sty might be the problem as this is the only package to change recently.  Can anyone suggest a workaround?  MWE  \listfiles \documentclass{article} \usepackage{colortbl} \begin{document} \begin{tabular}{l}   \hline   No space below with \texttt{colortbl.sty} loaded. \\[10mm]   \hline \end{tabular} \end{document}   File versions in use:   article.cls    2014/09/29 v1.4h Standard LaTeX document class   size10.clo    2014/09/29 v1.4h Standard LaTeX file (size option) colortbl.sty    2012/02/13 v1.0a Color table columns (DPC)    array.sty    2018/04/07 v2.4g Tabular extension package (FMi)    color.sty    2016/07/10 v1.1e Standard LaTeX Color (DPC)    color.cfg    2016/01/02 v1.6 sample color configuration   pdftex.def    2018/01/08 v1.0l Graphics/color driver for pdftex Closing as "off topic" has just gotten painful I know that useability and friendliness are given priority in the features implemented on StackExchange, but after using the new close-as-off-topic flow for the first time I would have to say I'm somewhat underwhelmed.  Why do we not have a simple It's off topic type reason? And why do I have to write half a book chapter as my custom close reason, especially when I can go back and edit the automatically posted comment so that it's way shorter?   This question complaint is prompted by  here on Meta. It's off topic, plain and simple. We now have a bunch of people wanting to close it, all potentially writing their own custom close reasons, it's just messy suboptimal. Regardless of how nice and friendly you want to be to the user, this particular question shouldn't need an explanation.    Does the off topic flow have to stay this way? Can we allow higher rep users to close as off topic without having to specify a (really long) custom reason, maybe have some canned reasons like we used to?  Edit: just to be clear, there are still three canned close reasons, but none of them were applicable to this example. The second one is closest, but does not appear to seek input... is quite different to It's a question, but doesn't belong here in any way, shape, or form. If $\lim_{x\to+\infty}[f(x+1)-f(x)]= \ell,$ then $\lim\limits_{x\to+\infty}\frac{f(x)}x=\ell$. Let $f:[0,+\infty)\to\Bbb R$ be a function bounded on each finite interval. I want to show that if $\lim\limits_{x\to+\infty}[f(x+1)-f(x)]= L,$ then also $\lim\limits_{x\to+\infty}\dfrac{f(x)}x = L$ I must have a blind spot, but I cannot find what it is.   I made a small python script that removes VLC from the sound menu. It runs perfectly in any way I run it from the terminal or from a launcher or whatever you can think of.   What the script actually does is nothing more than get the get the current settings:  gsettings get com.canonical.indicator.sound interested-media-players   edit the list, and set the changed list by:  gsettings set com.canonical.indicator.sound interested-media-players "['newlist']"   These commands are executed by a python script,. However, when run from a cronjob (crontab -e) only the gsettings - get - part works, but not the gsettings - set - section. That the get section works fine with cron, I checked by making the script write data (the original as well as the edited) to an external file.  Not a python problem  To see if the problem is related to python code, I created a bash script that applies a changed sound menu items list. The story is the same: the bash script runs fine from the command line or a launcher, not from cron, while any other command in the same script would run fine. Also, if I add any command at the end of the script below, it works fine and it looks like the script is satisfied with its own work.  Why is the gsettings set command not working when initiated from cron?  This is the script:  #!/usr/bin/python3 import subprocess  def read_soundmenu():     # read the current launcher contents     get_menuitems = subprocess.Popen([         "gsettings", "get", "com.canonical.indicator.sound", "interested-media-players"         ], stdout=subprocess.PIPE)     return eval((get_menuitems.communicate()[0].decode("utf-8")))  def set_current_menu(current_list): # this takes no effect from cron     # preparing subprocess command string     current_list = str(current_list).replace(", ", ",")     subprocess.Popen([         "gsettings", "set", "com.canonical.indicator.sound", "interested-media-players",         current_list,         ])  current_list = read_soundmenu() for item in current_list:     if item == "vlc.desktop":         current_list.remove(item) set_current_menu(current_list) I came across this statement while studying electric currents and I am confused:  "There is no electric field inside a conductor. Hence no current can flow through it".  Is there a fallacy in this statement?  Any help would be appreciated.  The conductor being discussed is ideal. What is the driving force for the current in this case? Best way to find a point on a circle closest to a given point Given a point (pX, pY) and a circle with a known center (cX,cY) and radius (r), what is the shortest amount of code you can come up with to find the point on the circle closest to (pX, pY) ?  I've got some code kind of working but it involves converting the circle to an equation of the form (x - cX)^2 + (y - cY)^2 = r^2 (where r is radius) and using the equation of the line from point (pX, pY) to (cX, cY) to create a quadratic equation to be solved.  Once I iron out the bugs it'll do, but it seems such an inelegant solution. How can I check the SMART status of a SSD or HDD on current versions of Ubuntu 14.04 through 20.04? How can I check the SMART status of a drive under 14.04 and beyond? I've seen  but it doesn't seem to apply under 14.04 and later.