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The following example shows a basic main GUI window with a label widget, a toolbar, and a status bar using PyQt4. import sys from PyQt4 import QtGui class App(QtGui.QApplication): def __init__(self, sys_argv): super(App, self).__init__(sys_argv) self.build_ui() ...

The hashlib module allows creating message digest generators via the new method. These generators will turn an arbitrary string into a fixed-length digest: import hashlib h = hashlib.new('sha256') h.update(b'Nobody expects the Spanish Inquisition.') h.digest() # ==> b'.\xdf\xda\xdaVR[\x12\...

This method looks for the existence of browser specific things. This would be more difficult to spoof, but is not guaranteed to be future proof. // Opera 8.0+ var isOpera = (!!window.opr && !!opr.addons) || !!window.opera || navigator.userAgent.indexOf(' OPR/') >= 0; // Firefox 1.0+ ...

Let's add a custom operator to multiply a CGSize func *(lhs: CGFloat, rhs: CGSize) -> CGSize{ let height = lhs*rhs.height let width = lhs*rhs.width return CGSize(width: width, height: height) } Now this works let sizeA = CGSize(height:100, width:200) let sizeB = 1.1 * si...

When you are copying a string into a malloced buffer, always remember to add 1 to strlen. char *dest = malloc(strlen(src)); /* WRONG */ char *dest = malloc(strlen(src) + 1); /* RIGHT */ strcpy(dest, src); This is because strlen does not include the trailing \0 in the length. If you take the ...

If realloc fails, it returns NULL. If you assign the value of the original buffer to realloc's return value, and if it returns NULL, then the original buffer (the old pointer) is lost, resulting in a memory leak. The solution is to copy into a temporary pointer, and if that temporary is not NULL, th...

Detailed instructions on getting asp.net-mvc-4 set up or installed.

Floating point types (float, double and long double) cannot precisely represent some numbers because they have finite precision and represent the values in a binary format. Just like we have repeating decimals in base 10 for fractions such as 1/3, there are fractions that cannot be represented fini...

PREPARE prepares a statement for execution EXECUTE executes a prepared statement DEALLOCATE PREPARE releases a prepared statement SET @s = 'SELECT SQRT(POW(?,2) + POW(?,2)) AS hypotenuse'; PREPARE stmt2 FROM @s; SET @a = 6; SET @b = 8; EXECUTE stmt2 USING @a, @b; Result: +------------+ |...

One of the most common things you'll need to do in the command prompt is navigate your file system. To do this, we'll utilize the cd and dir keywords. Start by opening up a command prompt using one of the methods mentioned here. You most likely see something similar to what's below, where UserNam...

WebGL is a browser technology so there isn't much to set up other than to have a browser. You can get started with WebGL on JSFiddle or Codepen or JSBIn or any number of other sites that let you edit HTML, CSS, and JavaScript online though there will be a few limitations (see below). You can also ho...

Using the calendar module import calendar from datetime import date def monthdelta(date, delta): m, y = (date.month+delta) % 12, date.year + ((date.month)+delta-1) // 12 if not m: m = 12 d = min(date.day, calendar.monthrange(y, m)[1]) return date.replace(day=d,month=m, year=...

Download driver via nuget. Using this command in the package manager console Install-Package mongocsharpdriver

#include <stdio.h> #include <stdlib.h> int main (void) { int * pdata; size_t n; printf ("Enter the size of the array: "); fflush(stdout); /* Make sure the prompt gets printed to buffered stdout. */ if (1 != scanf("%zu", &n)) /* If zu is n...

Detailed instructions on getting pymongo set up or installed. Installing with Pip To install pymongo for the first time: pip install pymongo Installing a specific version of pymongo: Where X.X.X is the version to be installed pip install pymongo==X.X.X Upgrading existing pymon...

Adding a Conditional attribute from System.Diagnostics namespace to a method is a clean way to control which methods are called in your builds and which are not. #define EXAMPLE_A using System.Diagnostics; class Program { static void Main() { ExampleA(); // This method will ...

Whitespace is handled by the lexical analyzer before being parsed. The lexical analyzer uses a stack to store indentation levels. At the beginning, the stack contains just the value 0, which is the leftmost position. Whenever a nested block begins, the new indentation level is pushed on the stack, ...

Creating a custom directive with isolated scope will separate the scope inside the directive from the outside scope, in order to prevent our directive from accidentally change the data in the parent scope and restricting it from reading private data from the parent scope. To create an isolated scop...

Mongoose populate is used to show data for referenced documents from other collections. Lets say we have a Person model that has referenced documents called Address. Person Model var Person = mongoose.model('Person', { fname: String, mname: String, lname: String, address: {typ...

Components are simply instances that implement the Ashley component class. import com.badlogic.ashley.core.Component; import com.badlogic.ashley.core.ComponentMapper; public class Position implements Component { public static final ComponentMapper<Position> Map = ...