Use tcolorboxes as nodes to create arrows with tikz
How to draw arrows between colourboxes
I'm trying to simulate a media key press using a custom shortcut.  So far, I've been able to achieve the simulation I need using the command:  xdotool key XF86AudioPlay   It works perfectly, it pauses or starts the music player every time it is run.  The problem comes when trying to run it as a shortcut.  First I tried to run an alias with a custom shortcut, but it did not work.  As explained on :     The commands run by keyboard bindings are not parsed via a shell. Your best bet is to create a directory bin in your homedir.   Next I created the suggested script and named it simplay:  #!/bin/sh xdotool key XF86AudioPlay   It is located inside a bin folder which is part of the PATH, this works fine and can be run from any location.  When trying to create the Custom Shortcut, I was unable to get it to execute, the configuration is the following:  Name: test Command: simplay  Shortcut: Ctrl+Alt+R   After searching a bit more I found another way to execute the shortcut:  gnome-terminal -e simplay   I tried it on a terminal and noticed that when executing it it would rapidly open a new terminal window, execute the child process, pausing the music and immediately close the window.  I changed the command on the shortcut and when hitting it I noticed the same behavior opening a terminal and immediately being closed but this time the child process did not pause the music, which makes me think that the script has been called on all my previous attempts but it is somehow not being able to execute.  How can I solve this problem according to your knowledge? How to understand degrees of freedom? From , there are three interpretations of the degrees of freedom of a statistic:     In statistics, the number of degrees of freedom is the number of   values in the final calculation of a statistic that are free to vary.      Estimates of statistical parameters can be based upon different   amounts of information or data. The number of independent pieces of   information that go into the estimate of a parameter is called the   degrees of freedom (df). In general, the degrees of freedom of an   estimate of a parameter is equal to the number of independent scores   that go into the estimate minus the number of parameters used as   intermediate steps in the estimation of the parameter itself (which,   in sample variance, is one, since the sample mean is the only   intermediate step).      Mathematically, degrees of freedom is the dimension of the domain of a   random vector, or essentially the number of 'free' components: how   many components need to be known before the vector is fully   determined.   The bold words are what I don't quite understand. If possible, some mathematical formulations will help clarify the concept.  Also do the three interpretations agree with each other? I was able to read and write NTFS filesystems normally in Mountain Lion, but after the upgrade this stopped to work.  I installed ntfs-3g and fuse4x using homebrew in Mountain Lion and followed the instructions displayed by homebrew to finish the installation of fuse4x kernel extension.  To try to solve this problem I removed ntfs-3g, fuse4x and fuse4x-kext and reinstalled them. But this didn't solve my problem.  Does anyone know how to solve this? Thanks. Must an uncountable subset of R have uncountably many accumulation points? Using Google Music Manager in Linux from the command line My goal is to use Google Music Manager on a Linux server.  I'm wondering if the music manager can operate from the command line and with no GUI.  If I could set the software up to watch a particular directory on the server and upload from there, that would be the only necessary functionality.  Thank you. escaping double quotes and percent signs (%) in cron The following command works from prompt but not from crontab.   grep abc  /var/log/messages | grep "`date '+%B %d'`" | mail -s"abc log of `hostname`" shantanu.oak+`hostname`@gmail.com   I need to add it to daily cron. PHP syntax for dereferencing function result Let $a$ and $b$ be positive reals. Show that $$\lim\limits_{n\to\infty} \left(\frac{a^{\frac{1}{n}}+b^{\frac{1}{n}}}{2}\right)^n =\sqrt{ab}$$ Javascript close alert box I want to be able to close an alert box automatically using Javascript after a certain amount of time or on a specific event (i.e. onkeypress).  From my research, it doesn't look like that's possible with the built-in alert() function.  Is there a way to override it and have control over the dialog box that it opens?  Also, I don't want an override that shows a hidden div as the alert.  I need an actual dialog box. How we can show every permutation is either even or odd,but not both......I can't arrive at a proof for this ..... Can anybody give me the proof...  Thanks in advance... GCSE: Find the number of person that will go to a party Short Question:  Why can we manipulate a read-only file in Vim using : + w + q + ! even without being an administrator?  Long Question:  I have a text file (myFile.txt) which is read-only for everyone:  navid@navid-ThinkPad-T530:~/ubuntuTest$ ls -l myFile.txt  -r--r--r-- 1 navid navid 26 Aug 22 21:21 myFile.txt   I can open it with Vim without having admin privileges:  navid@navid-ThinkPad-T530:~/ubuntuTest$ vi myFile.txt    I modify it and press: Esc + : + w + q + Enter and I see this error message:  E45: 'readonly' option is set (add ! to override)   So far, everything makes sense.  But when I press: Esc + : + w + q + ! + Enter, Vim saves the changes.  I'm using Ubuntu 16.04 and VIM 7.4. As the title say, I want to prove that  $C_c^{\infty}(\mathbb R^n)$ is dense in $W^{k,p}(\mathbb R^n)$  i.e.  $\displaystyle{ W^{k,p} (\mathbb R^n) = W_0^{k,p}(\mathbb R^n)  \quad (\star)}$. In a book I found that in order to prove it, we need the following claim:  Claim: Let $\displaystyle{\zeta \in C^{\infty} ([0, \infty)) }$ such that $\zeta (t)  =1 $ for $ t \leq 1 $ and $\displaystyle{ \zeta (t) =0 }$ for $ t \geq 2$. For $R&gt;0$ and  $x \in \mathbb R^n$ define $\displaystyle{ \eta_R (x) = \zeta \left( \frac{|x|}{R} \right)}$. If $ \displaystyle{ u \in W^{k,p} ( \mathbb R^n) }$ with $1 \leq p &lt; \infty $ then, $\displaystyle{ \eta_R u \to u }$ in $W^{k,p}(\mathbb R^n) $ as $ R \to \infty$.  If I prove the claim then the $(\star)$ follows using mollifiers. But unfortuently I have stuck, with the proof of the claim.  Any ideas? What is $\arctan(x) + \arctan(y)$ I know $$g(x) = \arctan(x)+\arctan(y) = \arctan\left(\frac{x+y}{1-xy}\right)$$  which follows from the formula for $\tan(x+y)$. But my question is that my book defines it to be domain specific, by which I mean, has different definitions for different domains:  $$g(x) = \begin{cases}\arctan\left(\dfrac{x+y}{1-xy}\right), &amp;xy &lt; 1 \\[1.5ex]  \pi + \arctan\left(\dfrac{x+y}{1-xy}\right), &amp;x&gt;0,\; y&gt;0,\; xy&gt;1 \\[1.5ex]  -\pi + \arctan\left(\dfrac{x+y}{1-xy}\right), &amp;x&lt;0,\; y&lt;0,\; xy &gt; 1\end{cases}$$  Furthermore, When I plot the function $2\arctan(x)$, it turns out that the book definition is correct. I don't understand how such peculier definition emerges. Thank you. What is the difference between "Build and view" and "Compile"? Is there a built-in function to print all the current properties and values of an object? So what I'm looking for here is something like PHP's  function.  This is so I can debug my scripts by seeing what's the state of the object in question. How to break multi digit number into separate digits in VHDL? I found the method .But I do not know how to perform this in VHDL. Let a fixed point number (12 downto -19) like 3456.478396 I need break this number entirely into separate numbers 3456.478396 --> 3,  4, 5,  6,  (dot) ,  4,  7,  8,  3,  9,  6...  into 11 integer type variables. How to perform this in VHDL?  signal example : sfixed(4 downto -4); --'example' contains 9.75 then it is storage as "01001.1100". --simply example ="10011100". --10011100 --&gt; integer 156   How to get back original 9.75 number from 156 to separate into single digits?  I USED,  library ieee; library ieee_proposed; use ieee.std_logic_1164.all; use ieee.numeric_std.all; use ieee_proposed.float_pkg.ALL; use ieee_proposed.fixed_pkg.ALL; use ieee_proposed.fixed_float_types.ALL; I don't understand, because if 'don't' is 'do not' then wouldn't the sentence without conjunctions be 'do not you dare' which I'm pretty sure isn't grammatically correct. Like, when we say the term it means something else, certainly not 'do not you dare' anyway. Any ideas on why? I am so glad English is my first language. Mouse rotated 90 degrees "In a party people shake hands with one another" In a party people shake hands with one another (not necessarily everyone with everyone else).   (a) Show that 2 people shake hands the same no. of times.   (b) Show that the number of people who shake hands an odd no. of time is even.        I find this question to be very tough and I can't find a way to even start answering this. It would be great if I could get a small hint in order for me to at least start it.