Tutorial by Examples: a

Absolute Path to Static Files Directory Example

// Set up Express var express = require('express'); var app = express(); // Serve files from the absolute path of the directory app.use(express.static(__dirname + '/public')); // Start Express server app.listen(3030);

express • Handling static files

Absolute Path to Directory & Virtual Path Prefix Example

// Set up Express var express = require('express'); var app = express(); /* Serve from the absolute path of the directory that you want to serve with a */ virtual path prefix app.use('/static', express.static(__dirname + '/public')); // Start Express server app.listen(3030);

express • Handling static files

Join two files read with textFile()

Joins in Spark: Read textFile 1 val txt1=sc.textFile(path="/path/to/input/file1") Eg: A B 1 2 3 4 Read textFile 2 val txt2=sc.textFile(path="/path/to/input/file2") Eg: A C 1 5 3 6 Join and print the result. txt1.join(txt2).foreach(p...

apache-spark • Text files and operations in Scala

Map, filter, and reduce

Two of the most fundamental higher-order functions included in the standard library are map and filter. These functions are generic and can operate on any iterable. In particular, they are well-suited for computations on arrays. Suppose we have a dataset of schools. Each school teaches a particular...

Julia Language • Higher-Order Functions

Apple's IFA vs. IFV (Apple Identifier for Advertisers vs. Identifier for Vendors)

You can use the IFA for measuring ad clicks and the IFV for measuring app installs. IFA has built-in privacy mechanisms that make it perfect for advertising. In contrast, the IFV is for developers to use internally to measure users who install their apps. IFA ASIdentifierManager class pr...

iOS • UUID (Universally Unique Identifier)

Pitfall - Using "Yoda notation" to avoid NullPointerException

A lot of example code posted on StackOverflow includes snippets like this: if ("A".equals(someString)) { // do something } This does "prevent" or "avoid" a possible NullPointerException in the case that someString is null. Furthermore, it is arguable that ...

Java Language • Java Pitfalls - Nulls and NullPointerException

"Hello World" as a library

This example shows how to deploy the "Hello World" program as a library and how to link it with other targets. Say we have the same set of source/header files as in the http://www.riptutorial.com/cmake/example/22391/-hello-world--with-multiple-source-files example. Instead of building fro...

cmake • Getting started with cmake

When are bit-fields useful?

A bit-field is used to club together many variables into one object, similar to a structure. This allows for reduced memory usage and is especially useful in an embedded environment. e.g. consider the following variables having the ranges as given below. a --> range 0 - 3 b --> range 0 -...

C Language • Bit-fields

Basic PL/pgSQL Trigger Function

This is a simple trigger function. CREATE OR REPLACE FUNCTION my_simple_trigger_function() RETURNS trigger AS $BODY$ BEGIN -- TG_TABLE_NAME :name of the table that caused the trigger invocation IF (TG_TABLE_NAME = 'users') THEN --TG_OP : operation the trigger was fired IF (TG_O...

postgresql • Triggers and Trigger Functions

_design/example

Design documents contain application logic. Any document in a database that has an _id starting with "_design/" can be used as design document. Usually there is one design document for each application. { "_id": "_design/example", "view": { ...

couchdb • Design Documents

Assignments model in PL/SQL

All programming languages allow us to assign values to variables. Usually, a value is assigned to variable, standing on left side. The prototype of the overall assignment operations in any contemporary programming language looks like this: left_operand assignment_operand right_operand instructions_...

plsql • Assignments model and language

Setting and getting pixel values of a Gray image in C++

// PixelAccessTutorial.cpp : Defines the entry point for the console // Environment: Visual studio 2015, Windows 10 // Assumptions: Opecv is installed configured in the visual studio project // Opencv version: OpenCV 3.1 #include "stdafx.h" #include<opencv2/core/core.hpp> #i...

opencv • Pixel Access

Angular 2 for-loop

For live plnkr click... <!doctype html> <html> <head> <title>ng for loop in angular 2 with ES5.</title> <script type="text/javascript" src="https://code.angularjs.org/2.0.0-alpha.28/angular2.sfx.dev.js"></script> <scr...

Angular 2 • Angular - ForLoop

Selecting by multiple criteria [C#]

It's also possible to use selectors together. This is done by using the OpenQA.Selenium.Support.PageObjects.ByChained object: element = driver.FindElement(new ByChained(By.TagName("input"), By.ClassName("class")); Any number of Bys can be chained and are used as an AND type ...

selenium-webdriver • Locating Web Elements

Canny Algorithm - C++

Below is an usage of canny algorithm in c++. Note that the image is first converted to grayscale image, then Gaussian filter is used to reduce the noise in the image. Then Canny algorithm is used for edge detection. // CannyTutorial.cpp : Defines the entry point for the console application. // En...

opencv • Edge detection

Reading .gz textfile line after line

This class open a .gz file (usual format of compressed log files) and will return a line at each call of .NextLine() There is no memory usage for temporary decompression, very useful for large file. Imports System.IO Class logread_gz Private ptr As FileStream Private UnGZPtr As Compress...

Visual Basic .NET Language • Reading compressed textfile on-the-fly

Extract the text contents from a div with a particular id

Taggy-lens allows us to use lenses to parse and inspect HTML documents. #!/usr/bin/env stack -- stack --resolver lts-7.0 --install-ghc runghc --package text --package lens --package taggy-lens {-# LANGUAGE OverloadedStrings #-} import qualified Data.Text.Lazy as TL import qualified Data.Tex...

Haskell Language • Parsing HTML with taggy-lens and lens

Installation or Setup

Detailed instructions on getting phonegap-build set up or installed.

phonegap-build • Getting started with phonegap-build

Array in CFScript

<cfscript> oneDimensionArray = ArrayNew(1); oneDimensionArray[1] = 1; oneDimensionArray[2] = 'one'; oneDimensionArray[3] = '1'; </cfscript> <cfif IsDefined("oneDimensionArray")> <cfdump var="#oneDimensionArray#"> </cfif>...

coldfusion • ColdFusion Arrays

Android Studio update channels

Overview Android Studio's built-in update mechanism can be set to receive updates through any one of these four channels: Canary: Bleeding edge, released about weekly. These are early previews released in order to obtain real-world feedback during development. The canary channel will always have...

android-studio • Android Studio updates