Tutorial by Examples: r

Elixir / Phoenix Install Homebrew first: /usr/bin/ruby -e "$(curl -fsSL https://raw.githubusercontent.com/Homebrew/install/master/install)" Then running brew install elixir will install both Elixir and it's dependency - Erlang. Install mix with mix local.hex. Install Phoenix as per ...

Writing and executing a simple TestNG program is mainly 3 step process. Code - write business logic of your test and annotate it with TestNG annotations Configure - add information of your test in testng.xml or in build.xml Run TestNG - it can be invoked from command line, ANT, IDE like Eclipse...

You might have realized that $emit is scoped to the component that is emitting the event. That's a problem when you want to communicate between components far from one another in the component tree. Note: In Vue1 you coud use $dispatch or $broadcast, but not in Vue2. The reason being that it doesn'...

This code places the hint text at form load and manipulates it as follows: C# private void Form_load(object sender, EventArgs e) { textBox.Text = "Place Holder text..."; } private void textBox_Enter(object sender, EventArgs e) { if(textBox.Text == "Place Holder text....

Project is following the structure from the Angular2 Quickstart guide here. RootOfProject | +-- app | |-- app.component.ts | |-- main.ts | |-- pipeUser.component.ts | \-- sanitize.pipe.ts | |-- index.html |-- main.html |-- pipe.html main.ts import { bootstrap } from '@angu...

<?php // hook into the init action and call create_book_taxonomies when it fires add_action( 'init', 'create_book_taxonomies', 0 ); // create taxonomy genres for the post type "book" function create_book_taxonomies() { // Add new taxonomy, make it hierarchical (like categorie...

UWP applications can easily store simple settings in a key/value store locally or even in the cloud so your application or a game can share settings between different user's devices. Following data types can be used for settings: UInt8, Int16, UInt16, Int32, UInt32, Int64, UInt64, Single, Double...

Real life use cases for Singleton pattern; If you are developing a client-server application, you need single instrance of ConnectionManager, which manages the life cycle of client connections. The basic APIs in ConnectionManager : registerConnection: Add new connection to existing list of connec...

A processing instruction is used to directly pass on some information or instruction to the application via the parser. <?my-application some instructions ?> The token after the initial question mark (here my-application) is called the target and identifies the application at which the ins...

Example of Receiver Operating Characteristic (ROC) metric to evaluate classifier output quality. ROC curves typically feature true positive rate on the Y axis, and false positive rate on the X axis. This means that the top left corner of the plot is the “ideal” point - a false positive rate of zero...

In most cases, the range_lookup is used as FALSE (an exact match). The default for this parameter is TRUE - it is less commonly used in this form, but this example shows one usecase. A supermarket gives a bonus based on the customers monthly spend. If the customer spends 250 EUR or more in a mon...

For accessing Cassandra cassandra-driver module from DataStax can be used. It supports all the features and can be easily configured. const cassandra = require("cassandra-driver"); const clientOptions = { contactPoints: ["host1", "host2"], keyspace: "te...

This basic Lucene example creates a simple index, and searches on it. Note: RAMDirectory creates a memory-resident index, and is handy for experimenting and testing, but in practice most people will need to have an index stored in the file system (see FSDirectory.open). import java.io.IOException...

While standard LaTeX is all that is needed for most simple mathematical formulae and equations, sometimes more symbols and tools are needed. There are multiple packages available that will enhance your equations and provide you with more to work with. Three of the main packages are described below. ...

Let's say you cannot find the symbol you need anywhere. You can create a custom symbol. For example, the code \documentclass{article} \usepackage{graphicx,amsmath,amssymb} \DeclareRobustCommand{\diamondtimes}{% \mathbin{\text{\rotatebox[origin=c]{45}{$\boxplus$}}}% } \begin{document} $a\d...

Matrices You must always use the amsmath package if you are going to use the following commands. There are four main types of matrix, as shown in the code below: \begin{matrix} a & b \\ c & d \end{matrix} \quad \begin{pmatrix} a & b \\ c & d \end{pmatrix} ...

Possible values are Continue | Ignore | Inquire | SilentlyContinue | Stop | Suspend. Value of this parameter will determine how the cmdlet will handle non-terminating errors (those generated from Write-Error for example; to learn more about error handling see [topic not yet created]). Default valu...

string setting = IsolatedStorageSettings.ApplicationSettings["Key"] as string;

The gridspec package allows more control over the placement of subplots. It makes it much easier to control the margins of the plots and the spacing between the individual subplots. In addition, it allows for different sized axes on the same figure by defining axes which take up multiple grid loca...

This is a simple implementation of Binary Search Tree Insertion using Python. An example is shown below: Following the code snippet each image shows the execution visualization which makes it easier to visualize how this code works. class Node: def __init__(self, val): self.l_chil...