Tutorial by Examples: en

CHICKEN is a Scheme interpreter and compiler with its own extension module system called "eggs". It is capable of compiling Scheme to native code by first compiling Scheme to C. Installing Debian or Ubuntu or other derived distros: sudo apt-get install chicken-bin Fedora / RHEL / Ce...

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

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'])

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: += -= *= /= %= &= |= ^= <<= >>=

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...

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...

Selenium is a set of tools designed to automate browsers. It is commonly used for web application tests across multiple platforms. There are a few tools available under the Selenium umbrella, such as Selenium WebDriver(ex-Selenium RC), Selenium IDE and Selenium Grid. WebDriver is a remote control i...

{ "some_string": null, "ather_string": "something" } If we will use this way: JSONObject json = new JSONObject(jsonStr); String someString = json.optString("some_string"); We will have output: someString = "null"; So we need to...

BEGIN UPDATE Employees SET PhoneNumber = '5551234567' WHERE Id = 1; UPDATE Employees SET Salary = 650 WHERE Id = 3; END

String concatenation can be performed using the + operator. For example: String s1 = "a"; String s2 = "b"; String s3 = "c"; String s = s1 + s2 + s3; // abc Normally a compiler implementation will perform the above concatenation using methods involving a StringBui...

> ourList = [1,2,3,4,5] [1,2,3,4,5] : List number > > firstElement = List.head ourList Just 1 : Maybe Int > > allButFirst = List.tail ourList Just [2,3,4,5] : Maybe (List Int) This wrapping into Maybe type happens because of the following scenario: What should List.head ret...

List.map : (a -> b) -> List a -> List b is a higher-order function that applies a one-parameter function to each element of a list, returning a new list with the modified values. import String ourList : List String ourList = ["wubba", "lubba", "dub",...

def numberOrCharacterSwitch(toggleNumber: Boolean)(number: Int)(character: Char): String = if (toggleNumber) number.toString else character.toString // need to explicitly specify the type of the parameter to be curried // resulting function signature Boolean => String val switchBetween3A...

Flask lets you use templates for dynamic web page content. An example project structure for using templates is as follows: myproject/ /app/ /templates/ /index.html /views.py views.py: from flask import Flask, render_template app = Flask(__name__) @app...

Full example code included at the end Windows components for OpenGL WGL WGL (can be pronounced wiggle) stands for "Windows-GL", as in "an interface between Windows and OpenGL" - a set of functions from the Windows API to communicate with OpenGL. WGL functions have a wgl prefix...

var MyDict = new Dictionary<string,T>(StringComparison.InvariantCultureIgnoreCase)

Any text following a " character on the same line is commented out: DATA ls_booking TYPE flightb. " Commented text

Grand Central Dispatch works on the concept of "Dispatch Queues". A dispatch queue executes tasks you designate in the order which they are passed. There are three types of dispatch queues: Serial Dispatch Queues (aka private dispatch queues) execute one task at a time, in order. They a...

3.0 To run tasks on a dispatch queue, use the sync, async, and after methods. To dispatch a task to a queue asynchronously: let queue = DispatchQueue(label: "myQueueName") queue.async { //do something DispatchQueue.main.async { //this will be called in main t...

Java doesn't provide a direct method in java.util.Arrays to remove an element from an array. To perform it, you can either copy the original array to a new one without the element to remove or convert your array to another structure allowing the removal. Using ArrayList You can convert the array t...