Tutorial by Examples: e

Basic Responsive Application

package { import flash.display.Sprite; import flash.display.StageAlign; import flash.display.StageScaleMode; import flash.events.Event; public class Main extends Sprite { //Document Class Main Constructor public function Main() { ...

ActionScript 3 • Responsive Application Design

Compare NSURL

NSString *urlString = @"https://www.stackoverflow.com"; NSURL *myUrl = [NSURL URLWithString: urlString]; NSURL *myUrl2 = [NSURL URLWithString: urlString]; if ([myUrl isEqual:myUrl2]) return YES;

Objective-C Language • NSURL

Using IBInspectable and IBDesignable

One (or two) of the coolest new features in recent Xcode releases are the IBInspectable properties and IBDesignable UIViews. These have nothing to do with the functionality of your application but instead impact the developer experience in Xcode. The goal is to be able to visually inspect custom v...

iOS • UIView

View logcat

You can run logcat as an adb command or directly in a shell prompt of your emulator or connected device. To view log output using adb, navigate to your SDK platform-tools/ directory and execute: $ adb logcat Alternatively, you can create a shell connection to a device and then execute: $ adb sh...

Android • ADB (Android Debug Bridge)

Installation or Setup

Detailed instructions on getting mapbox set up or installed.

mapbox • Getting started with mapbox

Iterating Over a Hash

A Hash includes the Enumerable module, which provides several iteration methods, such as: Enumerable#each, Enumerable#each_pair, Enumerable#each_key, and Enumerable#each_value. .each and .each_pair iterate over each key-value pair: h = { "first_name" => "John", "last_na...

Ruby Language • Hashes

Selecting with table alias

SELECT e.Fname, e.LName FROM Employees e The Employees table is given the alias 'e' directly after the table name. This helps remove ambiguity in scenarios where multiple tables have the same field name and you need to be specific as to which table you want to return data from. SELECT e.Fname,...

SQL • SELECT

Use the `email` as username and get rid of the `username` field

If you want to get rid of the username field and use email as unique user identifier, you will have to create a custom User model extending AbstractBaseUser instead of AbstractUser. Indeed, username and email are defined in AbstractUser and you can't override them. This means you will also have to r...

Django • Extending or Substituting User Model

Basic Setup

Backbone requires Underscore and (optionally) jQuery - for DOM manipulation (using Backbone.View) and RESTful persistence. The quickest way to get up and running with Backbone is to create an index.html file with simple script tags in the HTML <head>: <html> <head> ...

backbone.js • Getting started with backbone.js

CREATE TABLE With FOREIGN KEY

Below you could find the table Employees with a reference to the table Cities. CREATE TABLE Cities( CityID INT IDENTITY(1,1) NOT NULL, Name VARCHAR(20) NOT NULL, Zip VARCHAR(10) NOT NULL ); CREATE TABLE Employees( EmployeeID INT IDENTITY (1,1) NOT NULL, FirstName VARCHA...

SQL • CREATE TABLE

Parsing dates when reading from csv

You can specify a column that contains dates so pandas would automatically parse them when reading from the csv pandas.read_csv('data_file.csv', parse_dates=['date_column'])

pandas • Pandas IO tools (reading and saving data sets)

Example usage

Read text file from path: val sc: org.apache.spark.SparkContext = ??? sc.textFile(path="/path/to/input/file") Read files using wildcards: sc.textFile(path="/path/to/*/*") Read files specifying minimum number of partitions: sc.textFile(path="/path/to/input/file&qu...

apache-spark • Text files and operations in Scala

Recursive functions

A recursive function is a function that calls itself in its definition. For example the mathematical function, factorial, defined by factorial(n) = n*(n-1)*(n-2)*...*3*2*1. can be programmed as def factorial(n): #n here should be an integer if n == 0: return 1 else: ...

Python Language • Functions

sealed

When applied to a class, the sealed modifier prevents other classes from inheriting from it. class A { } sealed class B : A { } class C : B { } //error : Cannot derive from the sealed class When applied to a virtual method (or virtual property), the sealed modifier prevents this method (proper...

C# Language • Keywords

sizeof

Used to obtain the size in bytes for an unmanaged type int byteSize = sizeof(byte) // 1 int sbyteSize = sizeof(sbyte) // 1 int shortSize = sizeof(short) // 2 int ushortSize = sizeof(ushort) // 2 int intSize = sizeof(int) // 4 int uintSize = sizeof(uint) // 4 int longSize = sizeof(long) // 8 ...

C# Language • Keywords

Binary operators with assignment

C# has several operators that can be combined with an = sign to evaluate the result of the operator and then assign the result to the original variable. Example: x += y is the same as x = x + y Assignment operators: += -= *= /= %= &= |= ^= <<= >>=

C# Language • Operators

Sending a minimal HTTP request manually using Telnet

This example demonstrates that HTTP is a text-based Internet communications protocol, and shows a basic HTTP request and the corresponding HTTP response. You can use Telnet to manually send a minimal HTTP request from the command line, as follows. Start a Telnet session to the web server www.e...

HTTP • HTTP requests

HTTP Analytics through an Event Emitter

In the HTTP server code (e.g. server.js): const EventEmitter = require('events') const serverEvents = new EventEmitter() // Set up an HTTP server const http = require('http') const httpServer = http.createServer((request, response) => { // Handler the request... // Then emit an event...

Node.js • Event Emitters

Flash Develop Installation

FlashDevelop is a multi-platform open source IDE created in 2005 for Flash developers. With no cost, it's a very popular way to get started developing with AS3. To Install FlashDevelop: Download The Installation File and run the installer Once installation is complete, run FlashDevelop. On the ...

ActionScript 3 • Getting started with ActionScript 3

Apache Flex Installation

from http://flex.apache.org/doc-getstarted.html Download the SDK installer Run the SDK installer. The first question you will be asked is the installation directory. on a Mac, use /Applications/Adobe Flash Builder 4.7/sdks/4.14.0/ on a PC, use C:\Program Files(x86)\Adobe Flash Builder ...

ActionScript 3 • Getting started with ActionScript 3