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If the size of your content is fixed, you can use absolute positioning to 50% with margin that reduces half of your content's width and height: HTML <div class="center"> Center vertically and horizontally </div> CSS .center { position: absolute; background...

A common thought pattern for inexperienced Java programmers is that exceptions are "a problem" or "a burden" and the best way to deal with this is catch them all1 as soon as possible. This leads to code like this: .... try { InputStream is = new FileInputStream(fileName);...

function earlyexit { "Hello" return "World" } "Hello" will be placed in the output pipeline, "World" will not

build.gradle: dependencies { compile 'com.android.support:appcompat-v7:23.3.0' compile 'com.jakewharton.rxbinding:rxbinding-appcompat-v7:0.4.0' } menu/menu.xml: <menu xmlns:android="http://schemas.android.com/apk/res/android" xmlns:app="http://schemas.android.c...

One of the use cases of callback URLs is OAuth. Let us do this with an Instagram Login: If the user enters their credentials and clicks the Login button, Instagram will validate the credentials and return an access_token. We need that access_token in our app. For our app to be able to listen to suc...

Consider this example function to check if a host is up: is_alive() { ping -c1 "$1" &> /dev/null } This function sends a single ping to the host specified by the first function parameter. The output and error output of ping are both redirected to /dev/null, so the functi...

ssh -p 21 [email protected] <<EOF echo 'printing pwd' echo "\$(pwd)" ls -a find '*.txt' EOF $ is escaped because we do not want it to be expanded by the current shell i.e $(pwd) is to be executed on the remote shell. Another way: ssh -p 21 [email protected] <...

An extremely simple tool for installing PostgreSQL on a Mac is available by downloading Postgres.app. You can change preferences to have PostgreSQL run in the background or only when the application is running.

In order to determine some simple statistics of a value in a column of a table, you can use an aggregate function. If your individuals table is: NameAgeAllie17Amanda14Alana20 You could write this statement to get the minimum, maximum and average value: SELECT min(age), max(age), avg(age) FROM i...

On Debian or Ubuntu, you can install SCons using $ sudo apt-get install scons On YUM-based systems, use $ sudo yum install scons You can install using an RPM by downloading it, then running $ sudo rpm -Uvh http://prdownloads.sourceforge.net/scons/scons-2.5.0-1.noarch.rpm

stats::heatmap Example 1 (Basic usage) require(graphics); require(grDevices) x <- as.matrix(mtcars) rc <- rainbow(nrow(x), start = 0, end = .3) cc <- rainbow(ncol(x), start = 0, end = .3) hv <- heatmap(x, col = cm.colors(256), scale = "column", RowSideColo...

There are some cases in mixins where there can be single or multiple arguments while using it. Let's take a case of border-radius where there can be single argument like border-radius:4px; or multiple arguments like border-radius:4px 3px 2px 1px;. Traditional with Keyword Arguments mixing will be l...

If you are behind a proxy, you have to tell git about it: git config --global http.proxy http://my.proxy.com:portnumber If you are no more behind a proxy: git config --global --unset http.proxy

Texture units are global state. If they were implemented in JavaScript they would look something like this // pseudo code gl = { activeTextureUnit: 0, textureUnits: [ { TEXTURE_2D: ?, TEXTURE_CUBE_MAP: ? }, { TEXTURE_2D: ?, TEXTURE_CUBE_MAP: ? }, { TEXTURE_2D: ?, TEXTURE_CUBE_...

If you need to clamp a number to keep it inside a specific range boundary function clamp(min, max, val) { return Math.min(Math.max(min, +val), max); } console.log(clamp(-10, 10, "4.30")); // 4.3 console.log(clamp(-10, 10, -8)); // -8 console.log(clamp(-10, 10, 12)); // ...

To make long text at most N characters long but leave last word intact, use .{0,N}\b pattern: ^(.{0,N})\b.*

GNU Emacs uses a special format for documentation: info. The Common Lisp standard has been converted to the Texinfo format, which can be used to create documentation browsable with the info reader in GNU Emacs. See here: dpans2texi.el converts the TeX sources of the draft ANSI Common Lisp standard...

The axis offsets for drawing the marker that are specified by refX and refY are applied before the rotation specified by the orient parameter. Below you can see the effects of various combinations of orient and refX, refY to illustrate this. <svg width="800px" height="600px"&...

For some use cases, you can use the using syntax to help define a custom scope. For example, you can define the following class to execute code in a specific culture. public class CultureContext : IDisposable { private readonly CultureInfo originalCulture; public CultureContext(string ...

In simple terms: UNION joins 2 result sets while removing duplicates from the result set UNION ALL joins 2 result sets without attempting to remove duplicates One mistake many people make is to use a UNION when they do not need to have the duplicates removed. The additional performance cost...