Tutorial by Examples: l

List of Comparison Operators

OperatorComparisonExample==Equali == 0===Equal Value and Typei === "5"!=Not Equali != 5!==Not Equal Value or Typei !== 5>Greater thani > 5<Less thani < 5>=Greater than or equali >= 5<=Less than or equali <= 5

JavaScript • Comparison Operations

Creating a Simple VB.NET WinForms Application using a Text Editor

Open a text editor (like Notepad), and type the code below: Imports System.ComponentModel Imports System.Drawing Imports System.Windows.Forms Namespace SampleApp Public Class MainForm : Inherits Form Private btnHello As Button ' The form's constructor: thi...

winforms • Getting started with winforms

Cross Validation and Tuning with xgboost

library(caret) # for dummyVars library(RCurl) # download https data library(Metrics) # calculate errors library(xgboost) # model ############################################################################### # Load data from UCI Machine Learning Repository (http://archive.ics.uci.edu/ml/data...

R Language • xgboost

Overview of the basic path drawing commands: lines and curves

================== TODO: Link each of the drawing commands below to their individual examples. I don't know how to do this since the links to the individual examples point towards the "draft" folder. TODO: Add examples for these path "action" commands: stroke(), fill(), clip() ...

html5-canvas • Path (Syntax only)

lineTo (a path command)

context.lineTo(endX, endY) Draws a line segment from the current pen location to coordinate [endX,endY] <!doctype html> <html> <head> <style> body{ background-color:white; } #canvas{border:1px solid red; } </style> <script> window.onload=(fun...

html5-canvas • Path (Syntax only)

closePath (a path command)

context.closePath() Draws a line from the current pen location back to the beginning path coordinate. For example, if you draw 2 lines forming 2 legs of a triangle, closePath will "close" the triangle by drawing the third leg of the triangle from the 2nd leg's endpoint back to the firs...

html5-canvas • Path (Syntax only)

Elementary set operations

It's possible to perform elementary set operations with Matlab. Let's assume we have given two vectors or arrays A = randi([0 10],1,5); B = randi([-1 9], 1,5); and we want to find all elements which are in A and in B. For this we can use C = intersect(A,B); C will include all numbers which ...

MATLAB Language • Set operations

Installation or Setup

Linux Requirements (r0.16.0) Mandatory As per current Apache-Pig documentation it supports only Unix & Windows operating systems. Hadoop 0.23.X, 1.X or 2.X Java 1.6 or Later versions installed and JAVA_HOME environment variable set to Java installation directory Optional Python 2.7 ...

apache-pig • Getting started with apache-pig

Consuming a Successful Future

The easiest way to consume a successful Future-- or rather, get the value inside the Future-- is to use the map method. Suppose some code calls the divide method of the FutureDivider object from the "Creating a Future" example. What would the code need to look like to get the quotient of...

Scala Language • Futures

Consuming a Failed Future

Sometimes the computation in a Future can create an exception, which will cause the Future to fail. In the "Creating a Future" example, what if the calling code passed 55 and 0 to the divide method? It'd throw an ArithmeticException after trying to divide by zero, of course. How would t...

Scala Language • Futures

CROSS APPLY & LATERAL JOIN

A very interesting type of JOIN is the LATERAL JOIN (new in PostgreSQL 9.3+), which is also known as CROSS APPLY/OUTER APPLY in SQL-Server & Oracle. The basic idea is that a table-valued function (or inline subquery) gets applied for every row you join. This makes it possible to, for example...

SQL • JOIN

FULL JOIN

One type of JOIN that is less known, is the FULL JOIN. (Note: FULL JOIN is not supported by MySQL as per 2016) A FULL OUTER JOIN returns all rows from the left table, and all rows from the right table. If there are rows in the left table that do not have matches in the right table, or if there a...

SQL • JOIN

ESCAPE statement in the LIKE-query

If you implement a text-search as LIKE-query, you usually do it like this: SELECT * FROM T_Whatever WHERE SomeField LIKE CONCAT('%', @in_SearchText, '%') However, (apart from the fact that you shouldn't necessarely use LIKE when you can use fulltext-search) this creates a problem when someb...

SQL • LIKE operator

Rebuild index

Over the course of time B-Tree indexes may become fragmented because of updating/deleting/inserting data. In SQLServer terminology we can have internal (index page which is half empty ) and external (logical page order doesn't correspond physical order). Rebuilding index is very similar to dropping...

SQL • Indexes

Finding the minimum or maximum element

If your array or array-like object is numeric, that is, if all its elements are numbers, then you can use Math.min.apply or Math.max.apply by passing null as the first argument, and your array as the second. var myArray = [1, 2, 3, 4]; Math.min.apply(null, myArray); // 1 Math.max.apply(null, my...

JavaScript • Arrays

Loading default configuration

To read default configuration properties: package com.example; public class ExampleApplication { private Properties getDefaults() throws IOException { Properties defaults = new Properties(); try (InputStream defaultsStream = ExampleApplication.class.getResou...

Java Language • Resources (on classpath)

Find max and min Element and Respective Index in a Vector

To find the largest or smallest element stored in a vector, you can use the methods std::max_element and std::min_element, respectively. These methods are defined in <algorithm> header. If several elements are equivalent to the greatest (smallest) element, the methods return the iterator to th...

C++ • std::vector

Custom Tag Helper

You can create your own tag helpers by implementing ITagHelper or deriving from the convenience class TagHelper. The default convention is to target an html tag that matches the name of the helper without the optional TagHelper suffix. For example WidgetTagHelper will target a <widget> ta...

asp.net-core • Tag Helpers

Login View Component

The default project template creates a partial view _LoginPartial.cshtml which contains a bit of logic for finding out whether the user is logged in or not and find out its user name. Since a view component might be a better fit (as there is logic involved and even 2 services injected) the followin...

asp.net-core • View Components

Usage of alert()

The alert() method of the window object displays an alert box with a specified message and an OK or Cancel button. The text of that button depends on the browser and can't be modified. Syntax alert("Hello world!"); // Or, alternatively... window.alert("Hello world!"); Prod...

JavaScript • Modals - Prompts