When an answer has been deleted the information on unanswered question tabs still says that users modification was the last to the thread. For instance on Stack Overflow right now the top two  are listed as having been modified by .    While waiting for a moderator Zerkms, modified several answers in an effort to remove spam. However, once these answers were removed Zerkms still appears as the last person to modify the thread. While I imagine the hidden/deleted answers still exist somewhere causing this to occur, it can be confusing if you don't know why Zerkms is listed, as his modification is found nowhere within the linked question.  I would propose that when an answer / modification is deleted / rolled back, that the associated user is removed as the last modifier.
.       The  has no sign of the user sharth The  also does not have any sign of related activity   I would like to know why the user's name is associated with the question. At least why their display name shows up as having modified the question timeline activity.  Possible reason that I can think of is that, .  Is this the reason?  Is there a way (for normal users), to look for such details, other than looking at the user activity and the question's revision history.
I don't know how many of you have experienced the  principle when posting questions on SO, but I know I have on a few occasions. And then I just discard my question. So here's the question:  Should we go ahead and post the question?  Of course if it's something stupid like forgetting a semicolon, etc., I would say no... but there are several occasions, like if a data structure doesn't make sense, that at least someone would eventually benefit from the question/answers.  And if you should ask the question, how would you recommend choosing an answer for it? Show that when $BA = I$, the solution of $Ax=b$ is unique I'm just getting back into having to do linear algebra and I am having some trouble with some elementary questions, any help is much appreciated.  Suppose that $A = [a_{ij}]$ is an $m\times n$ matrix and $B = [b_{ij}]$ and is an $n\times m$ matrix and $BA = I$ the identity matrix that is $n \times n$.  Show that if for some $b \in \Bbb{R}^m$ the equation $Ax = b$ has a solution, then the solution is unique. What and where are the stack and heap? Programming language books explain that value types are created on the stack, and reference types are created on the heap, without explaining what these two things are. I haven't read a clear explanation of this.  I understand what a stack is. But,    Where and what are they (physically in a real computer's memory)? To what extent are they controlled by the OS or language run-time? What is their scope? What determines the size of each of them? What makes one faster? Review filter appears to be broken When browsing questions for a given tag, a review indicator has recently started showing up that links to the open review tasks for that tag.  For example, this is what I see when viewing :    The number 187 in the screenshot above would link to    However, clicking on that often opens review tasks that do not have the tag in question.  For example, it opened the following on successive attempts:   (c)   (java)  It seems that the filters are broken.  A sample screenshot (note the mention of the filter on the review page): What happened to the ia32-libs package? The ia32-libs package is no longer present in Ubuntu 12.04 repositories for a 64bit system. Are there any available replacement packages available for download? What's the physical meaning of the imaginary component of impedance? As you know, impedance is defined as a complex number.  Ideal capacitors: $$ \frac {1} {j \omega C} \hspace{0.5 pc} \mathrm{or} \hspace{0.5 pc} \frac {1} {sC} $$  Ideal inductors: $$ j \omega L \hspace{0.5 pc} \mathrm{or} \hspace{0.5 pc} sL $$  I know that the reason why they 'invented' the concept of impedance is because it makes it easy to work with circuits in the frequency domain (or complex frequency domain).  However, since in real-life circuits both voltages and currents are real numbers, I'm wondering if there is any actual physical meaning behind the imaginary component of impedance. How can I parse integers passed to an application as command line arguments if the app is unicode?  Unicode apps have a main like this:  int _tmain(int argc, _TCHAR* argv[])   argv[?] is a wchar_t*. That means i can't use atoi. How can I convert it to an integer? Is stringstream the best option? How to use the Bradhley Hand font? I've checked the  that can be used through beamer class. I've successfully used most of the fonts, but when I tried to include the Bradhley Hand font, it did not work (it shows ordinary characters)?! How can I use it?  For example, when I use the following :  \documentclass[serif]{beamer}  \usepackage{mathpazo}  \renewcommand{\rmdefault}{ibh}  \begin{document} \begin{frame} $\frac{ \sqrt{ \mu(i)^{ \frac{3}{2}} (i^{2} -1) } } { \sqrt[3]{\rho(i) - 2} + \sqrt[3]{\rho(i) - 1} } $ \end{frame} \end{document}   it gives: Minecraft Laucher has no Versions So this if the first time this has ever happened too me and I was wondering what it is. I just downloaded Minecraft and there is no area where i can change my version too 1.8.9/1.7.10 all i see when I do it is blank  Im just Wondering on how come even tho i hit the Repair button on the minecraft.msi download it dosnt fix it... If there is a way too fix this let me know cause my friend wants too play and I cant cause of this.. pass 1 environment variable using sudo Why is "letter" not plural in "two letter words"? Why is "letter" not plural in "two letter words"?  For me it's very strange as the equivalent in French would be plural but my English friend finds it totally normal. How do I upgrade to the unreleased version of Ubuntu for testing? How do I customize the context menu in Nautilus? ''will'' or ''going to'' An excited electron loses energy in the form of radiation. The radiation constitutes photons which move at a speed $c$. But is the process of conversion of the energy of the electron into the kinetic energy of the photon instantaneous? Is there a a simple way to visualize this process rather than math? Rewriting Triple Integral in different order How can I rewrite, say: $$\int^1_0\int^{z^2}_0\int^y_0{f}dxdydz$$ In the orders $dzdxdy$ and $dydzdx$?  Would I have to solve this triple integral all the way or is there a simple way to do this? Array#each vs. Array#map How to prove this result involving the quotient maps and connectedness? Given topological spaces $X$ and $Y$, where $Y$ is connected, let $p \colon X \to Y$ be a quotient map. If, for each point $y \in Y$, the set $p^{-1}(\{y\})$ is connected, then how to prove that $X$ is connected also?   By the map $p$ being a quotient map is meant the following:   The map $p$ is surjective, and, for any subset $V$ of $Y$, the set $V$ is open in $Y$ if and only if $p^{-1}(V)$ is open in $X$. Why do I get TypeError: can't multiply sequence by non-int of type 'float'? I'm kind of stuck in Terraria. I have full silver armor and 12 hearts (gold/silver gear).  I have just killed the Eye of Cthulhu.  I was thinking about gathering gold armor, but gold is damn scarce. I have tried searching for floating islands (at 406 altitude) but if I go to far I get attacked by Harpies, and I can't build a sky bridge and fight them at the same time.  My meteorite landed in corruption and it's impossible to collect it (I get swarmed by meteor heads with no way to run).  So what is the most natural progression? Should I try and find gold (where?), try to kill the Eater of Worlds, try to mine meteorite or try to fight off imps and collect some hellstone?