Where should I put my script so that I can run it by a direct command?
Is there a standard place for placing custom Linux scripts?
Would you ever stop rolling the die? Associativity of symmetric difference of sets How do I loop through or enumerate a JavaScript object? I have a JavaScript object like the following:  var p = {     "p1": "value1",     "p2": "value2",     "p3": "value3" };   Now I want to loop through all p elements (p1, p2, p3...) And get their keys and values. How can I do that?  I can modify the JavaScript object if necessary. My ultimate goal is to loop through some key value pairs and if possible I want to avoid using eval. I have a table:  table votes (     id,     user,     email,     address,     primary key(id), );   Now I want to make the columns user, email, address unique (together).  How do I do this in MySql?  Of course the example is just... an example. So please don't worry about the semantics. Boundary Question in $\mathbb{R}^{2}$ (Manifolds) How can I start learning about political philosophy? I'm interested in learning about political philosophy. What are the best ways to start? Are there any websites for beginners? Are there any books such as the "For Dummies" series? Are there any audio or video introductions to familiarize myself with the terminology? Finding a 2x2 Matrix raised to the power of 1000 Delete with Join in MySQL Here is the script to create my tables:   CREATE TABLE clients (    client_i INT(11),    PRIMARY KEY (client_id) ); CREATE TABLE projects (    project_id INT(11) UNSIGNED,    client_id INT(11) UNSIGNED,    PRIMARY KEY (project_id) ); CREATE TABLE posts (    post_id INT(11) UNSIGNED,    project_id INT(11) UNSIGNED,    PRIMARY KEY (post_id) );   In my PHP code, when deleting a client, I want to delete all projects posts:  DELETE  FROM posts INNER JOIN projects ON projects.project_id = posts.project_id WHERE projects.client_id = :client_id;   The posts table does not have a foreign key client_id, only project_id. I want to delete the posts in projects that have the passed client_id.  This is not working right now because no posts are deleted. Connect Tikz nodes via two parallel arrows I am just starting to learn using Tikz and am a little lost within its seemingly infinite amount of options and possibilities.  What I am trying to do is visualize a few Matlab function interaction (which one calls which one, what is the in- and output). Since there are only about six subroutines, I place each one manually as a node. This is an example:  \documentclass{article} \usepackage{tikz} \usetikzlibrary{shapes,positioning}  \begin{document}  \begin{tikzpicture}[auto] \node           [rounded rectangle,draw]        (node1)     {Node 1}; \coordinate [above=of node1]                                (input); \node           [rounded rectangle,draw]    at  (-10:6cm) (node2)       {Node 2}; \draw           [-&gt;,very thick]             ([xshift=0.1cm]  input.south)  --                  node {right}                ([xshift=0.1cm]  node1.north); \draw           [-&gt;,very thick]             ([xshift=-0.1cm] node1.north) --                  node {left}                 ([xshift=-0.1cm] input.south); \draw                                            (node1) -- (node2);  \end{tikzpicture}  \end{document}     Now I would like to apply these double in/out arrows I (probably pretty awkwardly) created using xshift to all node connections, so in this example also for the connection between Node 1 and Node 2. Ideally, the space between these two arrows would be the same, independant of their angle and they would nicely connect to the outer line of the nodes. Any idea how I could achieve this? Similar questions I have found only used rectangle and orthogonal lines. There are a few examples of pairs of words ending with -ee/-er like employee and employer or advisee and adviser. What I was curious about is if there was any rule that would describe the relationship of the objects in a pair like this and situations when it's appropriate to create a counterpart for a given word.   I'll give you an example. It's relatively common in the computer programming world to see the word dragee, which describes an object that is being dragged with a mouse. I understand that this is a relatively new word and could not be found in any dictionary (I've tried). Is that acceptable to make up words like this one or is it just bad English? What's the simplest way to list conflicted files in Git? Highlight elements in the matrix I have a matrix and need to highlight some elements in the matrix. I have found how to highlight a single element (I want to put the cell in the square):  $$ A = \begin{bmatrix} \fbox{0} &amp; \fbox{0} &amp; 0 \\  \fbox{0} &amp; \fbox{0} &amp; 0 \\ 1 &amp; 1 &amp; 1 \\  \end{bmatrix}$$   But how can I outline elements of the submatrix like in the picture below? I need just a frame where some elements are located. Reset post score to 0 on migration Evaluating the integral $\int \frac{x^2+x}{(e^x+x+1)^2}dx$ I would like to create a minecraft server for me and and my boyfriend to play on.  How do I set it up? Do I need any additional software? Do you have some links to walkthroughs or tutorials?  I have tried to set this up a few times but have failed every time. Why did Dumbledore drink the potion in the attempt to get a Horcrux? I have read that positional parameters start at $1 (for example: $1, $2, $3 and so on are positional parameters). But $0 is not a positional parameter.  But why $0 is not a positional parameter?  I think this could be a reason, but not sure:  Positional parameters only take their values when a script is executed. For example: if we do ./myScript Hello, then $1 will have the value Hello. But $0 can take its value on two occasions: when a script is executed (it would have the value of the script name), and when bash itself is executed without a script (it would have the value bash or -bash). finding $\int_0^\infty \dfrac{dx}{1+x^4}$ through complex analysis java.io.Console support in Eclipse IDE I use the Eclipse IDE to develop, compile, and run my Java projects. Today, I'm trying to use the java.io.Console class to manage output and, more importantly, user input.  The problem is that System.console() returns null when an application is run "through" Eclipse. Eclipse run the program on a background process, rather than a top-level process with the console window we're familiar with.  Is there a way to force Eclipse to run the program as a top level process, or at least create a Console that the JVM will recognize? Otherwise, I'm forced to jar the project up and run on a command-line environment external to Eclipse. I have a directory which contains numbered image files, something like this:  01.png 02.png 03.png 03.svg 04.png 05.png 06.jpg 07.png 08.png 09.png 09.svg 10.png   Sometimes there may be multiple versions of a file in different formats (eg. a png and svg version of the 03 and 09 files above) but the numbers are otherwise consecutive.  Typically there are 40-80 such files in each directory.  The numbers correspond to the order these images appear in a manuscript (a Word document, but that's not important).  There is no other way to determine the order of the images.  If I add a new image to the manuscript I need to place a copy of the image in this directory with the correct numbering.  So if the new image is the fifth in the manuscript I need to rename the files in the directory to this in order to make room for it:  01.png 02.png 03.png 03.svg 04.png 06.png 07.jpg 08.png 09.png 10.png 10.svg 11.png   What is the most straightforward way from the command line, or from a script or macro to renumber all the files starting at a certain number?  I have a standard Fedora Linux install using bash.