Why cannot we comment-reply more than one person in comments, and anyone in questions/answers? I think the comment-reply (ping) mechanism is way too limited. You can only reply to one person in a comment. And you can't use an @ whatsoever in questions and answers. It just doesn't make sense to me.   Sometimes, when responding to a chain of comments, multiple commenters might be making the same point or similar points, and your answer to them might be the same. Therefore, it would be better to be able to comment-reply to all of the users in one comment, instead of posting multiple comments or only responding to one of them.  On a question asked before about this, user Manishearth answered that one can just add a comment under with the other user's name.  Not only is this less practical, but a few problems can arise.   Firstly, what if there is a lot of people you want to ping? If the comment chain gets too long everyone is moved to chat, which might not work too well in every situation.   Secondly, in a case of a sea of comments, your extra referral might get lost in all the comments, leaving the user tagged oblivious as to what comment they were actually tagged to.   In questions and answers, there are many times were pinging someone would be quite beneficial. Just look at this question, where notifying user Manishearth of his mention would've been great, as I'd be able to get his opinion, and he would be aware if I was using his name in vain (or just misrepresenting his opinions or answers).  If your question includes or links to a post of another user, then it would be great to be able to ping them. Or if the question is about something a user said, like this question:   And in questions, there are many times you find yourself quoting or pointing to something another user has already said. What if we could instead of just give credit to them, also let them know we referenced something they said first.  If there is a reason why this wouldn't work, or would be bad, please enlighten me.
Allow more than one @name notification per comment Now this is probably a surprise to many since I always see thousands of comments like :  @Sarfraz, @balpha just told you they did in the first comment he wrote. Also, allowing only one Stack Overflow user to be logged in per IP address would be problematic for networks with shared IPs.  What's surprising is that apparently the notification will trigger only for Sarfraz and not for balpha. As you can see from the :  Only one person can be replied to at a time in a comment. The first one in the string wins.  I propose to increase the limit to let's say 3 or 5 people; it won't hurt (never seen that feature being abused) and especially many people believe it already works that way.
Left-align all equations in a block align environment without any explicit alignments points (given by &amp;) right justifies the equations in the block. They can be left justified by putting &amp; at the beginning of each equation. Is there any way to left justify them without starting &amp;-s? Maybe some special environment or option? It seems to be an extra work to tell the compiler again and again that I want left alignment on each line. I'm using latex on a small netbook, and with average-sized files (~150 pages at the moment) compilation is already pretty slow. So I am looking for every way to speed up the compilation.  In this search, I found  explaining how to "precompile a preamble", or, latexically-speaking, how to make a custom format file. That works fine enough.  But my preamble isn't as static as it should be, I keep adding or modifying definitions in there. To mix the two solutions, at the moment, I use a Makefile together with latexmk, the makefile handling the regeneration of the .fmt file if needed, and latexmk taking good care of the rest.  But I have two problems with this :   integration with emacs to compile the whole document when working on a single file (make needs to be called in the proper directory) latexmk doesn't recompile the file every time the preamble is modified, because it doesn't count as a dependency.   So I'd like to find a way to get rid of this Makefile, and get all the stuff done by latexmk.  I edited my .latexmkrc to include this :     pdflatex = 'pdflatex -fmt main %O %S';  add_input_ext('pdflatex','fmt');  add_cus_dep('tex', 'fmt', 1, 'compilepreamble'); sub compilepreamble {     print "Preamble compiling...\n";     $command = '&amp;.pdflatex ./fmt/preamble.tex\dump';     system("pdflatex -ini -jobname='$_[0]' '$command'"); };      But with this, if the file main.fmt is not present or if fmt/preamble.tex is updated, the main.fmt file won't be regenerated. Actually, in the first case, I get an error from pdflatex saying the it can't find main.fmt format file. So I understand latexmk doesn't even try to build main.fmt, it's probably not a problem in my custom dependency. However, I think I've added everything necessary for this to work.  So... Did I forget something? Is there a way round? Or is it a hopeless quest? I would like some help with this exercise.  Suppose that $f_1,\ f_2 \in V^*$ and that $\text{Ker} f_1 = \text{Ker} f_2$. Show that $f_1 = k f_2$ for some scalar $k$.  I expect your suggestions.  Thanks! iOS 9 Screen Recording in El Capitan I used to record iOS devices through QuickTime, however now it's only recording audio (not sure is this linked to OS X 10.11 or iOS 9).  How can I fix this (without third party sofrware)? A proof of the fact that the Fourier transform is not surjective from $\mathcal{L}^1(\mathbb{R})$ to $C_0( \mathbb{R})$ Let $f_n = \mathbb 1_{[-n,n]}$ for all $n \in \mathbb{N}$   Compute explicitly $f_n \star f_1$ for all $n \in \mathbb{N}$.  Show that $f_n \star f_1$ is the Fourier transform of $g_n = \frac{  \sin{(2\pi x)} \sin{(2 \pi nx)}}{\pi ^2 x^2}$  Show that $\| g_n \|_1 \to \infty$  Deduce that the Fourier transform is not surjective from $\mathcal{L}^1(\mathbb{R})$ to $C_0( \mathbb{R})$    Here, $C_0(\mathbb{R})$ is the space of continuous functions $f : \mathbb{R} \to \mathbb{R}$ that tends to $0$ at $-\infty$ and $+\infty$. I managed to compute 1) and proved 2). But I don't know how to prove 3). Moreover, I don't see how can 1), 2) and 3) prove 4). Can anyone help? Gnome Panel becomes fully transparent when window is not maximised! ImportError: No module named dbus I was trying to update my Python and messed up my whole system.   I am currently now able to start my Software Centre. I tried Googling multiple fixes but nothing helped. My Software Centre can't start.   When I try starting it up, this error shows:  astephen@localhost:/usr/bin$ ./software-centerGtk-Message: Failed to load module "gtk-vector-screenshot" Traceback (most recent call last): File "./software-center", line 36, in &lt;module&gt; from softwarecenter.utils import ( File "/usr/share/software-center/softwarecenter/utils.py", line 19, in &lt;module&gt; import dbus ImportError: No module named dbus   I tried reinstalling dbus using:  apt-get install --reinstall dbus   But it did not help.  astephen@localhost:/usr/bin$ sudo apt-get install --reinstall dbusReading package lists... Done Building dependency tree        Reading state information... Done 0 upgraded, 0 newly installed, 1 reinstalled, 0 to remove and 0 not      upgraded. Need to get 0 B/231 kB of archives. After this operation, 0 B of additional disk space will be used. (Reading database ... 676272 files and directories currently installed.) Preparing to unpack .../dbus_1.6.18-0ubuntu4.3_amd64.deb ... Unpacking dbus (1.6.18-0ubuntu4.3) over (1.6.18-0ubuntu4.3) ... Processing triggers for ureadahead (0.100.0-16) ... Processing triggers for man-db (2.6.7.1-1ubuntu1) ... Setting up dbus (1.6.18-0ubuntu4.3) ... I'm not sure if this is the right place to ask this question. I realise that this maybe a borderline philosophical question at this point in time, therefore feel free to close this question if you think that this is a duplicate or inappropriate for this forum. Anyway, I'm an electrical engineer and I have some basic knowledge of quantum mechanics. I know that Schrödinger's equation is deterministic. However, quantum mechanics is much deeper than that and I would like to learn more. If this question is not clearly answerable at this point than can anyone point out some recognized sources that try to answer this question. I would appreciate it if the source is scientific and more specifically, is related to quantum theory. How can I require an optional Perl module if installed? I have Perl code which relies on Term::ReadKey to get the terminal width. My installation is missing this module, so I want to provide a default if the module isn't present rather than throw an exception. How can I conditionally use an optional module, without knowing ahead of time whether it is available. # but only if the module is installed and exists use Term::ReadKey; ...  How can I accomplish this? TikZ Angle Label - Help it "fit" better? I have the following drawn with TikZ    using the code  \documentclass{article} \usepackage{tikz} \usepackage{tkz-euclide} \usetkzobj{all} \begin{document} \begin{tikzpicture} \coordinate (O) at (0,0); \draw (O) circle (3); \coordinate[label = above left:$M$] (M) at (130:3); \coordinate[label = above:$N$] (N) at (80:3); \coordinate[label = below:$A$] (A) at (240:3); \coordinate[label =below right:$B$] (B) at (300:3); \draw (A) -- (M) -- (B); \draw (A) -- (N) -- (B); \tkzMarkAngle[draw = black, fill = white, opacity=1](A,M,B) \tkzLabelAngle[pos = 0.8](A,M,B){$x$} \tkzMarkAngle[pos = 0.2,draw = black, fill = white, opacity=1](A,N,B) \tkzLabelAngle [pos=0.8](A,N,B){$27 ^{\circ}$} \end{tikzpicture} \end{document}   Notice however, tht the 27 degrees does not fit in very nicely. How can I adapt the code to try and move the 27 a bit "lower" so that it fits in better, as well as the angle mark?  Also, how can I get two "double arrows" in the middle of lines AM and BN, to indicate that they are 'parallel'? I came across this strange limit whilst showing convergence of a series: $$\lim_{n \to \infty}\sqrt[n]{\frac{2^n+3^n}{3^n+4^n}}$$ How can I calculate this limit? How can I turn off "middle mouse button paste" functionality in all programs? I don't like having the middle mouse button paste, because I often end up with uncompilable code in Eclipse. How can I turn this off (in all programs)? I'm running Fedora. Is there an easy way to get to www.stackexchange.com from any of the SE sites? One thing I've noticed about the relatively new sitewide layout is that I can't find a quick way to get back to www.stackexchange.com without finding StackExchange in the sites list. As a result, I am typing stackexchange in my toolbar a whole lot more often now. In particular, I tend to enjoy browsing the hot questions list and my own personal feed quite often so visit these pages on a daily basis. Is there an easy link to them that I'm missing?  (On the android app, there is a feed in the menu that I really appreciate, something like that on the desktop would be ideal!) tikz trees: How to not draw a single edge What is the easiest way to handle huge numbers in C? I need to store values in the Area 1000^900, or in more human readable form 10^2700. Does anybody know of an easy way to do that? Any help would really be appreciated! Yesterday I had 3,606 reputation but today I have 3,592.  My profile shows that I lost 6 reputation when a user was removed, but that would put me on 3,600 - 8 reputation has magically disappeared.  Adding up all of my reputation does work out at 3,591 (I'm assuming by default new users have 1 rep, so that would make sense).  Somewhere a reputation change since yesterday isn't being displayed. I don't know what this would be for, but -8 would lead me to believe that someone removed their up-vote on an answer I'd posted which already had a down-vote (could it be from that deleted user?).  I don't know if this is a bug or if there is simply a delay between reputation updating, but I figured it was worth reporting.    Sadly I cannot prove that I had 3,606 reputation yesterday. How to open a particular port in ubuntu? My SoulSeek client Nicotine+ checks my open ports during initial configuration and promts that the one port number it needs is closed, cutting me off frmo about 50% of the users. Is there anyway I can open that particular port for the application to use?  RUnning ubuntu desktop 13.04. I have not manually installed any firewalls, but not sure if its included in the default installation. Why is the sum of two random variables a convolution? How to convert wstring into string? Cheese from UHT Milk I live in a town where fresh or whole milk is not readily available. I was wondering if I could make cheese from UHT Milk. If so, what kind of cheese and what method I should use? Or rather, Should I?