Tutorial by Examples: l

This example shows how to use two audio sources, and alter one of them based on the other. In this case we create an audio Ducker, that will lower the volume of the primary track if the secondary track produces sound. The ScriptProcessorNode will send regular events to its audioprocess handler. In ...

Matrix multiplication can be done in two equivalent ways with the dot function. One way is to use the dot member function of numpy.ndarray. >>> import numpy as np >>> A = np.ones((4,4)) >>> A array([[ 1., 1., 1., 1.], [ 1., 1., 1., 1.], [ 1., 1.,...

class Plane { enum Emergency: ErrorType { case NoFuel case EngineFailure(reason: String) case DamagedWing } var fuelInKilograms: Int //... init and other methods not shown func fly() throws { // ... if fuelInKilograms ...

const int a = 0; /* This variable is "unmodifiable", the compiler should throw an error when this variable is changed */ int b = 0; /* This variable is modifiable */ b += 10; /* Changes the value of 'b' */ a += 10; /* Throws a compiler error */ The const qualif...

process.argv is an array containing the command line arguments. The first element will be node, the second element will be the name of the JavaScript file. The next elements will be any additional command line arguments. Code Example: Output sum of all command line arguments index.js var sum = 0...

Here we make a simple echo websocket using asyncio. We define coroutines for connecting to a server and sending/receiving messages. The communcations of the websocket are run in a main coroutine, which is run by an event loop. This example is modified from a prior post. import asyncio import ai...

A singleton is a pattern that restricts the instantiation of a class to one instance/object. Using a decorator, we can define a class as a singleton by forcing the class to either return an existing instance of the class or create a new instance (if it doesn't exist). def singleton(cls): i...

Using vanilla mathematics: var from:Point = new Point(100, 50); var to:Point = new Point(80, 95); var angle:Number = Math.atan2(to.y - from.y, to.x - from.x); Using a new vector representing the difference between the first two: var difference:Point = to.subtract(from); var angle:Number ...

A whole circle is 360 degrees or Math.PI * 2 radians. Half of those values follows to be 180 degrees or Math.PI radians. A quarter is then 90 degrees or Math.PI / 2 radians. To get a segment as a percentage of a whole circle in radians: function getSegment(percent:Number):Number { retur...

Assuming you have the angle you'd like to move in and an object with x and y values you want to move: var position:Point = new Point(10, 10); var angle:Number = 1.25; You can move along the x axis with Math.cos: position.x += Math.cos(angle); And the y axis with Math.sin: position.y += Mat...

You can test whether a point is inside a rectangle using Rectangle.containsPoint(): var point:Point = new Point(5, 5); var rectangle:Rectangle = new Rectangle(0, 0, 10, 10); var contains:Boolean = rectangle.containsPoint(point); // true

Prerequesites Grunt requires Node.js and npm to be installed. If you don’t have Node.js and/or npm installed on your machine, go to https://nodejs.org and download the installer or package for your operating system. First-time install If you're installing Grunt for the first time, you'll first ha...

clojure.spec/and & clojure.spec/or can be used to create more complex specs, using multiple specs or predicates: (clojure.spec/def ::pos-odd (clojure.spec/and odd? pos?)) (clojure.spec/valid? ::pos-odd 1) ;;=> true (clojure.spec/valid? ::pos-odd -3) ;;=> false or works similarl...

You can spec collections in a number of ways. coll-of allows you to spec collections and provide some additional constraints. Here's a simple example: (clojure.spec/valid? (clojure.spec/coll-of int?) [1 2 3]) ;; => true (clojure.spec/valid? (clojure.spec/coll-of int?) '(1 2 3)) ;; => tru...

Sometimes you may only need to simulate an event with two outcomes, maybe with different probabilities, but you may find yourself in a situation that calls for many possible outcomes with different probabilities. Let's imagine you want to simulate an event that has six equally probable outcomes. T...

This example demonstrates creating a basic application in ExtJS using Sencha Cmd to bootstrap the process - this method will automatically generate some code and a skeleton structure for the project. Open a console window and change the working directory to an appropriate space in which to work. ...

A While loop starts by evaluating a condition. If it is true, the body of the loop is executed. After the body of the loop is executed, the While condition is evaluated again to determine whether to re-execute the body. Dim iteration As Integer = 1 While iteration <= 10 Console.Writeline(ite...

A package.json file, usually present in the project root, contains metadata about your app or module as well as the list of dependencies to install from npm when running npm install. To initialize a package.json type npm init in your command prompt. To create a package.json with default values use...

2.3-2.3.2 An enclosing CoordinatorLayout can be used to achieve Material Design Scrolling Effects when using inner layouts that support Nested Scrolling, such as NestedScrollView or RecyclerView. For this example: app:layout_scrollFlags="scroll|enterAlways" is used in the Toolbar pro...

Any time you instantiate a class that Implements IDisposable, you should call .Dispose1 on that class when you have finished using it. This allows the class to clean up any managed or unmanaged dependencies that it may be using. Not doing this could cause a memory leak. The Using keyword ensures th...