Tutorial by Examples: is

This example shows how a MongoDB collection can be displayed in a React component. The collection is continuously synchronized between server and client, and the page instantly updates as database contents change. To connect React components and Meteor collections, you'll need the react-meteor-data...

PMF FOR THE BINOMIAL DISTRIBUTION Suppose that a fair die is rolled 10 times. What is the probability of throwing exactly two sixes? You can answer the question using the dbinom function: > dbinom(2, 10, 1/6) [1] 0.29071 PMF FOR THE POISSON DISTRIBUTION The number of sandwhich ordered in ...

Instead of struct IShape { virtual ~IShape() = default; virtual void print() const = 0; virtual double area() const = 0; virtual double perimeter() const = 0; // .. and so on }; Visitors can be used: // The concrete shapes struct Square; struct Circle; // The v...

The Display Logic module allows you to add conditions for displaying or hiding certain form fields based on client-side behavior. This module is incredibly useful to make forms much more professional by showing only the appropriate fields and without adding a lot of custom JavaScript. Example usag...

Here we have a simple class to be tested that returns a Promise based on the results of an external ResponseProcessor that takes time to execute. For simplicty we'll assume that the processResponse method won't ever fail. import {processResponse} from '../utils/response_processor'; const ping =...

This function executes an AJAX request using the HEAD method allowing us to check whether a file exists in the directory given as an argument. It also enables us to launch a callback for each case (success, failure). function fileExists(dir, successCallback, errorCallback) { var xhttp = new XM...

You can also perform this task recursively, but I have chosen in this example to use an iterative approach. This task is useful if you are inserting all of your nodes at the beginning of a linked list. Here is an example: #include <stdio.h> #include <stdlib.h> #define NUM_ITEMS 10...

The Python interpreter compiles code to bytecode before executing it on the Python's virtual machine (see also What is python bytecode?. Here's how to view the bytecode of a Python function import dis def fib(n): if n <= 2: return 1 return fib(n-1) + fib(n-2) # Display the disas...

Here is a class (Dog) creating its own dependency (Food): class Dog { public Dog() { var food = new Food(); this.eat(food); } } Here is the same class being injected with its dependency using constructor injection: class Dog { public Dog(Food food) { ...

using System; using System.IO; public class Program { public static void Main() { string filePath = "somePath"; if(File.Exists(filePath)) { Console.WriteLine("Exists"); } else ...

Polymorphism is one of the pillar of OOP. Poly derives from a Greek term which means 'multiple forms'. Below is an example which exhibits Polymorphism. The class Vehicle takes multiple forms as a base class. The Derived classes Ducati and Lamborghini inherits from Vehicle and overrides the base cl...

Recursive type Discriminated unions can be recursive, that is they can refer to themselves in their definition. The prime example here is a tree: type Tree = | Branch of int * Tree list | Leaf of int As an example, let's define the following tree: 1 2 5 3 4 We can defi...

Polymorphism means that a operation can also be applied to values of some other types. There are multiple types of Polymorphism: Ad hoc polymorphism: contains function overloading. The target is that a Method can be used with different types without the need of being generic. Parametric polym...

You can use the $q.all function to call a .then method after an array of promises has been successfully resolved and fetch the data they resolved with. Example: JS: $scope.data = [] $q.all([ $http.get("data.json"), $http.get("more-data.json"), ]).then(funct...

The $q constructor function is used to create promises from asynchronous APIs that use callbacks to return results. $q(function(resolve, reject) {...}) The constructor function receives a function that is invoked with two arguments, resolve and reject that are functions which are used to eithe...

Even experienced Java developers tend to think that Java has only three protection modifiers. The language actually has four! The package private (a.k.a. default) level of visibility is often forgotten. You should pay attention to what methods you make public. The public methods in an application a...

These Java issues can be very embarrassing, and sometimes remain undiscovered until run in production. Fallthrough behavior in switch statements is often useful; however, missing a “break” keyword when such behavior is not desired can lead to disastrous results. If you have forgotten to put a “break...

The tree command lists the contents of a specified directory in a tree-like format. If no directory is specified then, by default, the contents of the current directory are listed. Example Output: $ tree /tmp /tmp ├── 5037 ├── adb.log └── evince-20965    └── image.FPWTJY.png Use the tree ...

curl -XGET http://www.example.com:9200/myIndexName/_search?pretty=true&q=*:* This uses the Search API and will return all the entries under index myIndexName. Reference Link: Here

To find active ScriptableObjects during runtime, you can use Resources.FindObjectsOfTypeAll(). T[] instances = Resources.FindObjectsOfTypeAll<T>(); Where T is the type of the ScriptableObject instance you're searching. Active means it has been loaded in memory in some form before. This me...