Tutorial by Examples: in

STEP 1: CREATE A DIRECTORY IN HDFS, UPLOAD A FILE AND LIST CONTENTS Let’s learn by writing the syntax. You will be able to copy and paste the following example commands into your terminal: hadoop fs -mkdir: Takes the path URI’s as an argument and creates a directory or multiple directories. Usag...

You can combine the results of two identically structured queries with the UNION keyword. For example, if you wanted a list of all contact info from two separate tables, authors and editors, for instance, you could use the UNION keyword like so: select name, email, phone_number from authors u...

So you want to deploy your app to multiple sites? and your project has too many dependencies to install them one-by-one? Npm has a solution just issue the following command: npm init In the project's root folder then follow the instructions on screen (type in the desired value then press enter) ...

In many languages, new instances of a class are created using a special new keyword. In Ruby, new is also used to create instances of a class, but it isn't a keyword; instead, it's a static/class method, no different from any other static/class method. The definition is roughly this: class MyClass ...

This example sorts elements in ascending order of a key using a map. You can use any type, including class, instead of std::string, in the example below. #include <iostream> #include <utility> #include <map> int main() { std::map<double, std::string> sorted_map; ...

To detect the endian of the device var isLittleEndian = true; (()=>{ var buf = new ArrayBuffer(4); var buf8 = new Uint8ClampedArray(buf); var data = new Uint32Array(buf); data[0] = 0x0F000000; if(buf8[0] === 0x0f){ isLittleEndian = false; } })(); Lit...

db.people.createIndex({name: 1}) This creates an ascending single field index on the field name. In this type of indexes the sort order is irrelevant, because mongo can traverse the index in both directions.

Pattern matching extensions for C# enable many of the benefits of pattern matching from functional languages, but in a way that smoothly integrates with the feel of the underlying language switch expression Pattern matching extends the switch statement to switch on types: class Geometry {} cl...

The Timeline object allows you to get the execution time for each node in the graph: you use a classic sess.run() but also specify the optional arguments options and run_metadata you then create a Timeline object with the run_metadata.step_stats data Here is an example program that measures...

1. Setup your formatter and routing in Register of (App_Start/WebApiConfig) public static class WebApiConfig { public static void Register(HttpConfiguration config) { GlobalConfiguration.Configuration.Formatters.Clear(); GlobalConfiguration.Configuration.Formatters.Add...

To make a script to replace a phrase use the ::abbreviation:: hotstring syntax. It will replace btw with by the way whenever you enter btw and then the space key. ::btw::by the way If you wanted to make a login script to make logging in faster you could make a script like this (the file is not e...

A model represents some data object in an application. For example you can have a model such as: Fruit, Car, Building, etc. in your application. Models are normally used by stores. Here is example how you would define a new model class. e.g. Ext.define('MyApp.model.Person', { extend: 'Ext.data...

When should I use it When the code inside an inline listener is too big and your method / class becomes ugly and hard to read You want to perform same action in various elements (view) of your app To achieve this you need to create a class implementing one of the listeners in the View API. ...

The NVIDIA installation guide ends with running the sample programs to verify your installation of the CUDA Toolkit, but doesn't explicitly state how. First check all the prerequisites. Check the default CUDA directory for the sample programs. If it is not present, it can be downloaded from the offi...

There are two ways to setup the Apache Flex SDK. You can use the provided Apache Flex SDK Installer, an Adobe AIR application that automates the process (on Windows or OS X/macOS). Or you can install it manually which obviously requires a greater comfort with your platform but provides more flexibi...

public class Sheep { private String name; private int weight; public Sheep(String name, int weight) { this.name = name; this.weight = weight; } public static Sheep newInstance(Sheep other); return new Sheep(other.name, other.wei...

To show and hide a FloatingActionButton with the default animation, just call the methods show() and hide(). It's good practice to keep a FloatingActionButton in the Activity layout instead of putting it in a Fragment, this allows the default animations to work when showing and hiding. Here is an ...

String templates are a convenient way of mixing literal strings with values from variables: WRITE |Hello, { lv_name }, nice to meet you!|. It can also format things like dates. To use the logged on user's date format: WRITE |The order was completed on { lv_date DATE = USER } and can not be chan...

Suppose we have the following XAML snippet: <ListBox x:Name="MyListBox" /> Then in the code-behind for this XAML file, we write the following in the constructor: MyListBox.ItemsSource = new[] { 1, 2, 3, 4, 5 }; Running the application, we get a list of numbers we enter...

CREATE DATABASE LINK dblink_name CONNECT TO remote_username IDENTIFIED BY remote_password USING 'tns_service_name'; The remote DB will then be accessible in the following way: SELECT * FROM MY_TABLE@dblink_name; To test a database link connection without needing to know any of the objec...