I'd like to be able to filter users
Add the ability to ignore users
How can I determine whether my processor is 32-bit or 64-bit? My processor is AMD Phenom 8450 triple-core. Compilation problem with siunitx (returning error regarding ifnum) I'm trying to get siunitx working. For some reason I keep getting this error:  ! Missing = inserted for \ifnum. &lt;to be read again&gt;                     - l.3 \begin           {document}^^M   I have tried a minimal document to make sure it is not some kind of compatibility issue. And I get that same error in the most minimal document possible.  I'm using pdfLaTeX to compile, and have tried both from TeXWorks and from bash. I'm using TeXLive, if that matters. I have also tried reinstalling siunitx, l3packages, and l3kernel. There was an issue with l3kernel before this, due to an apparently old version. But all three packages are now up to date. I've also reinstalled expl3 while trying to debug the original issue.  My minimal document is:  \documentclass{article} \usepackage{siunitx} \begin{document} \end{document}   The output I get is:  This is pdfTeX, Version 3.14159265-2.6-1.40.16 (TeX Live 2015/Debian) (preloaded format=pdflatex) restricted \write18 enabled. entering extended mode (./untitled-2.tex LaTeX2e &lt;2016/02/01&gt; Babel &lt;3.9q&gt; and hyphenation patterns for 81 language(s) loaded. (/usr/share/texlive/texmf-dist/tex/latex/base/article.cls Document Class: article 2014/09/29 v1.4h Standard LaTeX document class (/usr/share/texlive/texmf-dist/tex/latex/base/size10.clo)) (/home/&lt;name&gt;/texmf/tex/latex/siunitx/siunitx.sty (/home/&lt;name&gt;/texmf/tex/latex/l3kernel/expl3.sty (/home/&lt;name&gt;/texmf/tex/latex/l3kernel/expl3-code.tex) (/home/&lt;name&gt;/texmf/tex/latex/l3kernel/l3pdfmode.def)) (/home/&lt;name&gt;/texmf/tex/latex/l3packages/xparse/xparse.sty) (/usr/share/texlive/texmf-dist/tex/latex/amsmath/amstext.sty (/usr/share/texlive/texmf-dist/tex/latex/amsmath/amsgen.sty)) (/usr/share/texlive/texmf-dist/tex/latex/tools/array.sty) (/home/&lt;name&gt;/texmf/tex/latex/l3packages/l3keys2e/l3keys2e.sty) (/usr/share/texlive/texmf-dist/tex/latex/beamer/translator/translator.sty (/usr/share/texlive/texmf-dist/tex/latex/graphics/keyval.sty) (/usr/share/texlive/texmf-dist/tex/latex/beamer/translator/translator-language- mappings.tex))) ! Missing = inserted for \ifnum. &lt;to be read again&gt;                    - l.3 \begin          {document}^^M ?   Does anyone have any idea what might be going wrong here? Why I can't scan the WhatsApp QR? Choosing between meaningful and meaningless hostnames pgfplots - barplot with multiple bars on same coordinate, but labelled differently I'm showing several data sets next to each other using multiple \addplot commands within a pgfplots axis environment. These are then further grouped into categories. The output of the graph per se is fine, however, I need each bar to be labelled separately - basically, I want the legend to be displayed directly underneath its corresponding element. I presume a picture will illustrate my problem more clearly:     I prepared an MWE:  \documentclass{minimal} \usepackage{pgfplots}  \begin{document}  \pgfplotstableread{ 0 35569 8842    134984   1 30428 4689    34077 2 32920 6207    73787    3 16462 7562    23496    4 12315 8572    16565    5 76572 19572   26030    }\dataset \begin{tikzpicture} \begin{axis}[ybar,         width=.9\textwidth,         ymin=0,         ymax=150000,                 ylabel={Y-Label},         xtick=data,         xticklabels = {             Category 1,             Category 2,             Category 3,             Category 4,             Category 5,             Category 6         },         major x tick style = {opacity=0},         minor x tick num = 1,         minor tick length=2ex,         ] \addplot[draw=black,fill=black!20] table[x index=0,y index=1] \dataset; %Data1 \addplot[draw=black,fill=black!40] table[x index=0,y index=2] \dataset; %Data2 \addplot[draw=black,fill=black!60] table[x index=0,y index=3] \dataset; %Data3 \legend{Data1,Data2,Data3} \end{axis}  \end{tikzpicture}  \end{document} For example, if I have a lens that is 16mm-50mm, which focal length would be the closest to the human eye's view? (I don't have a camera yet, so I'm just curious.)   Would 50mm be more zoomed in than "normal"?  I imagine 16mm would be wider than the normal human point of view? Where can I ask Android related questions in Stack Exchange? I would like to know where I can ask Android apps and other mobile related questions. Is there a Stack Exchange site for such questions? Cheaper alternative to parmesan cheese? The parmesan cheese in pasta recipe is quite expensive.....do we have cheaper alternative??  Are there are cheddar cheese which can replace parmesan cheese? I often see "replace with" and "replace by" used interchangeably, but this doesn't sound right to me:     I replaced that component by this one.   I would use "with" in such a sentence. "By" only seems reasonable in passive, although "with" sounds like it would there work too:     That component was replaced by this one.   That component was replaced with this one.   In my native language, the equivalent of "replace by" can only be used in passive, and even then it's a bit weird unless a person is the object replacing something – perhaps this affects my judgment?  Web searches haven't come up with anything conclusive; the results are contradictory and speculative at best.  Are "replace with" and "replace by" interchangeable in active context? What about passive? Are there stylistic reasons to prefer one over the other? Can a function be differentiable at the end points of its (closed interval) domain? Assume $f$ has a domain of $[a,b]$. Is it possible that $f$ is differentiable on the closed interval $[a,b]$, or must the maximal domain for $f'$ be $(a,b)$? Django: AppRegistryNotReady() probability that exactly two accidents happen in any day of a week if 7 accidents happen in a week If 7 accidents happen in a week, what is the probability that exactly 2 accidents happen in any day of the week.  I tried to work it this way.  2 accidents out of 7 can be taken in ${7}\choose{2}$$= 21$.  Now this can happen in any of the 7 days, so we have $7 \times 21$.  Now, the remaining 5 can happen in $6^5$ ways.  So the probability is  $\frac{7\times 21 \times 6^5}{7^7} = \frac{3 \times 6^5}{7^5}$   But this gives me a value greater than 1.   I know I am doing something wrong.  Can anyone help me ? Let $E_n$ be $$E_n:=\{f\in C[0,1]\mid \text{exist } x_f\in[0,1] \text{ such that } |f(x)-f(x_f)|\leq n|x-x_f|,\, \forall x\in[0,1]\}.$$  How show that $E_n$ is nowhere dense, that is, $\mathrm{int}\  \overline{E_n} = \emptyset$?  Can someone help me? Does the sign of $\Delta x$ matter in this time dilation calculation? I was confused initially about what the pins mean next to a topic in the new help center.  "those articles are "featured" articles; they are meant to draw attention to the most important site policies or most frequently encountered issues."   If the pin is used to denote an important topic, it should at least be noted as such. Also a pin generally means to me that this is something that I personally selected.  Could their meaning be clarified somehow? How do I detach a process from Terminal, entirely? I use Tilda (drop-down terminal) on Ubuntu as my "command central" - pretty much the way others might use GNOME Do, Quicksilver or Launchy.  However, I'm struggling with how to completely detach a process (e.g. Firefox) from the terminal it's been launched from - i.e. prevent that such a (non-)child process   is terminated when closing the originating terminal  "pollutes" the originating terminal via STDOUT/STDERR   For example, in order to start Vim in a "proper" terminal window, I have tried a simple script like the following:  exec gnome-terminal -e "vim $@" &amp;&gt; /dev/null &amp;   However, that still causes pollution (also, passing a file name doesn't seem to work). Is there a "null coalescing" operator in JavaScript? Is there a null coalescing operator in Javascript?  For example, in C#, I can do this:  String someString = null; var whatIWant = someString ?? "Cookies!";   The best approximation I can figure out for Javascript is using the conditional operator:  var someString = null; var whatIWant = someString ? someString : 'Cookies!';   Which is sorta icky IMHO. Can I do better? What prefixes should be used on reference designators for components of various types?  I think we can all agree that "R##" refers to a resistor, "C##" refers to a capacitor, and "L##" refers to an inductor.  Beyond that, it appears to be a mishmash of conventions.    I've seen both "IC" and "U" used for chips.   "Q", "T", and "M" have been used for transistors and MOSFETs.  Ordinarily, "D##" is used for diodes, but LEDs and Zeners get special treatment on some boards.    What standards are available for reference, and who endorses them?  JEDEC, ISO, IEEE, and other standardization bodies are welcome references (though I'd prefer an inexpensive standard), but I'm also curious to see what's used at various companies other than my own.    Edit:  What I'd really like to see is a list in an answer here which complies with the standard (even if it's just a quote). How can I ensure that old documents will compile in the future? I am looking for a JavaScript array insert method, in the style of:  arr.insert(index, item)   Preferably in jQuery, but any JavaScript implementation will do at this point.