Evaluating the product of a matrix sequence
A Product function for matrix products
Batch Convert Images from One Format to Another while maintaining directory structure, and removing originals I've looked at , and while it works there a few issues:   All converted images are placed in the directory from which the command is called. The original images are kept.   I need to convert around 70,000 .tif and .jpgs to .pngs.  It's really important the the files when converted are placed in their normal directories.    I can do a batch rm of .tff/.jpg's at the end if that's the best way to handle removing the old files. How to prove this for positive real numbers? $$a+b+c\leq\frac{a^3}{bc}+\frac{b^3}{ca}+\frac{c^3}{ab}$$  I tried AM-GM, CS inequality but all failed. In 5e's version of the flesh to stone spell, if the spell is maintained for the full minute duration, the effect (petrification) lasts until "removed".  How can this petrification be removed? Do I need quote marks when I quote myself? Why didn't Aragorn keep going with the army of the dead? Mouse gestures for Unity desktop Mouse Pointer Locator Due to a stroke, I have had some vision impairment in that I sometimes have a hard time locating my mouse pointer on the screen.  I have tried making the mouse pointer larger which helps but is still not the solution.  I am new to the Mac world and would appreciate your help.  In Windows, there is an option where pressing the CTRL key will help to identify the mouse pointer using a temporary display of several radiating concentric circles around the mouse pointer.  Is there something like this on OS X? Some publications capitalize He, Him, etc., when referring to a god.    What is this practice called? 'Proper noun' is rather generic. How to backup an Android device? Can anyone recommend a good way to backup Android devices? Ideally I would like to do this wirelessly and, not only backup my data, but also my user settings. Is it possible to backup an image of an Android device - so that one doesn't even need to reinstall apps? It would be particularly useful to hear from users that have restored backups, as to how easy, and complete, their processes were. Thanks Libraries module. Where to extract? How does Ubuntu flavor iso differ from a desktop package? TL;DR: how does an Ubuntu flavor iso installation ( for example Lubuntu ) differ from installing a desktop package via apt-get ? (for instance sudo apt-get install lubuntu-desktop)  Context for the question:   Some time ago I answered a question on AskUbuntu , where I tested in virtual machine removing unity-desktop and installing ubuntu-gnome-desktop. That makes the boot logo ( plymouth ) change, desktop changes, different packages get installed (gnome-network-manager instead of network-manager , if I am not mistaken). It appeared that in effect I've switched to different Ubuntu flavor, even though I started out with the standard Ubuntu system. Hence the question: what differentiates the pre-made Ubuntu flavor iso from installing a package ? Is it all the same base underneath the hood or does installation from iso have specific configurations ? If it's possible to install a flavor via package manager, why then separate flavor iso's exist ? (obvious answer is user convenience, but I think there has to exist other reasons. Canonical is a business , and it makes not a lot of sense for a business to provide additional flavor iso , if a sysadmin or end-user can get the same thing via package manager by themselves). B2B application: users has its own users B2B Scenario I am trying is that:  The following Roles exists in the system:  Super Admin Super Admin Staff Owner (client) Admin (owner i.e. client and creates admin to define sales counters) Sales Counters  That means there are users who'll create their own sub users e.g.  [FLAG-A] ROLE &quot;SUPER ADMIN&quot; creates a ROLE &quot;Owner&quot; and &quot;OWNER&quot; creates its own sub users ROLES i.e. &quot;ADMN&quot; &amp; &quot;SALES COUNTER&quot;. Each role obviously has its info to login to the system I tried to design database as following:  In this diagram I am assuming that main user creates sub user that in my view many to many relationship so I have to add table between them as &quot;USER_PERSON&quot;. Problem is to set &quot;WHO CREATED USER&quot; in the system. I mean which user has created sub user as described in [FLAG-A]  Please check this diagram How to reload a gem on every request in Development mode? I’m struggling with getting \ifmmode to work correctly when used inside an array environment which is inside a displaymath environment.  Here is a minimal example:  \documentclass{article}  \newcommand{\signal}[1]{%   \ifmmode     1#1   \else     2$#1$   \fi }  \begin{document} \begin{displaymath}   \begin{array}{cc}     \signal{a} \signal{b} &amp; \signal{c} \signal{d} \\   \end{array} \end{displaymath} \end{document}   This example generates the following output:        Why doesn’t all invokations of \signal detect math-mode? I do not want packages to be installed under /. (sudo apt-get install ...).   The reason why I need to do this is that:  My '/' is mounted with my SSD(16GB) and my hard disk(500GB) is mounted at '/home'.   I have already installed my Ubuntu 12.04 on that SSD. There is not much free space under '/' now. Why can't I have a non-integral static const member in a class? I noticed C++ will not compile the following:  class No_Good {   static double const d = 1.0; };   However it will happily allow a variation where the double is changed to an int, unsigned, or any integral type:  class Happy_Times {   static unsigned const u = 1; };   My solution was to alter it to read:  class Now_Good {   static double d() { return 1.0; } };   and figure that the compiler will be smart enough to inline where necessary... but it left me curious.  Why would the C++ designer(s) allow me to static const an int or unsigned, but not a double?  Edit: I am using visual studio 7.1 (.net 2003) on Windows XP.  Edit2:  Question has been answered, but for completion, the error I was seeing:  error C2864: 'd' : only const static integral data members can be initialized inside a class or struct Where can a tourist apply for a UK Visitor (standard) Visa? How to evaluate $\int_{0}^{+\infty}\exp(-ax^2-\frac b{x^2})\,dx$ for $a,b>0$ GPU usage monitoring (CUDA) I installed CUDA toolkit on my computer and started BOINC project on GPU. In BOINC I can see that it is running on GPU, but is there a tool that can show me more details about that what is running on GPU - GPU usage and memory usage? Macro for figure position? Why is the following minimal example not working?  I.e., what do I need to do, in order to define the float placement specifier of a figure within a macro? (I know that I should use \newcommand, but in the "full" example the error is part of an involved "superfigure" command. \newcommand is not working too btw.)  \documentclass{scrreprt} \usepackage{blindtext}  \def\PosNotWorking{h} \def\FramboxNotWorking{5cm} \def\CaptionWorking{Caption is working.}  \begin{document}  \Blindtext[1]  \begin{figure}[\PosNotWorking]   \centering     \framebox[5cm]{My special figure. (Pos: \PosNotWorking)}             \caption{\CaptionWorking} \end{figure}  \Blindtext[1]  \end{document}   If I compile this, the figure is at the top (default behaviour). If I enter \figure[h] instead of \figure[\PosNotWorking], the figure is of course between the two paragraphs.