Tutorial by Examples: dp

NSE functions should be used in interactive programming. However, when developping new functions in a new package, it's better to use SE version. Load dplyr and lazyeval : library(dplyr) library(lazyeval) Filtering NSE version filter(mtcars, cyl == 8) filter(mtcars, cyl < 6) filter(mtca...

A savepoint stores two things: (a) the positions of all datasources, (b) the states of operators. Savepoints are useful in many circonstances: slight application code updates Flink update changes in parallelism ... As of version 1.3 (also valid for earlier version): checkpoint must be ...

After you installed XAMPP and setup the MySQL database you can install WordPress. Download the latest version of WordPress. Unzip the file and insert the folder in the root directory of your webserver (if you used the suggested path during the setup of XAMPP it is "c:\xampp\htdocs"). ...

The sample command can be used to simulate classic probability problems like drawing from an urn with and without replacement, or creating random permutations. Note that throughout this example, set.seed is used to ensure that the example code is reproducible. However, sample will work without expl...

If you add this to your functions.php it removes the WordPress version number from the RSS feed and the header. function remove_wordpress_ver() { return ''; } add_filter('the_generator', 'remove_wordpress_ver', 999);

You can use any name for the function. function custom_postype(){ register_post_type('cus_post',array( 'labels'=>array( 'name'=>'khaiyam'// Use any name you want to show in menu for your users ), 'public'=>true,// **Must required ...

Instead of specifying connection parameters like user and password (see a complete list here) in the URL or a separate parameters, you can pack them into a java.util.Properties object: /** * Connect to a PostgreSQL database. * @param url the JDBC URL to connect to. Must start with "jdbc:...

The following code, inserted in your wp-config.php file, will log all errors, notices, and warnings to a file called debug.log in the wp-content directory. It will also hide the errors so they do not interrupt page generation. // Enable WP_DEBUG mode define( 'WP_DEBUG', true ); // Enable Debug...

Dialog dlg; DialogGroup dGrp; DialogField dialogField; dlg = new Dialog("Evil Dialog"); dGrp = dlg.addGroup("A Group"); dialogField = dlg.addFieldValue(extendedTypeStr(NoYesId), NoYes::Yes, "I hereby sell my soul"); if (dlg.run()) { info(dialogField.valu...

In C, pointers can be cast to a void*, which needs an explicit cast in C++. The following is illegal in C++, but legal in C: void* ptr; int* intptr = ptr; Adding an explicit cast makes this work, but can cause further issues.

Create a new rails app hello-world from command in Windows and Terminal in Linux. rails new hello-world Now move to new app directory cd hello-world Now generate a controller rails generate controller hello_world index Here index is the name of method in hello_world controller. You can c...

There are two ever-so-slightly different engines of regular expressions implemented in R. The default is called POSIX-consistent; all regex functions in R are also equipped with an option to turn on the latter type: perl = TRUE. Look-ahead/look-behind perl = TRUE enables look-ahead and look-behind...

Here, we try to explain OCP using codebase. First we'll show a scenario that violate OCP and then we'll remove that violation. Area Calculation (OCP violation Code) : public class Rectangle{ public double Width {get; set;} public double Height {get; set;} } public class Circle{ public do...

ng build –prod Above given command with extra option like –prod would generate the production build project bundle. Once the above command gets executed in the root directory of your project would appear a directory called dist. In which all the production build bundle of your project appears in ...

import * as React from 'react'; import * as ReactDOM from 'react-dom'; import { Route, BrowserRouter as Router, Link, match } from 'react-router-dom'; // define React components for multiple pages class Home extends React.Component<any, any> { render() { return ( <div&g...

This solution is more involved, leveraging custom TypeScript decorators which inject match, history and/or location data into your React.Component class, which gets you full type safety without needing any type guards, as the previous example required. // Routed.ts - defines decorators import { Ro...

dplyr uses Non-Standard Evaluation(NSE), which is why we normally can use the variable names without quotes. However, sometimes during the data pipeline, we need to get our variable names from other sources such as a Shiny selection box. In case of functions like select, we can just use select_ to u...

Simple Codec Here to illustrate the working principle we can use simple encryption and decryption as follows. public static String encrypt(String input) { // Simple encryption, not very strong! return Base64.encodeToString(input.getBytes(), Base64.DEFAULT); } public static String dec...

Simple Codec Here to illustrate the working principle we can use simple encryption and decryption as follows. public static String encrypt(String input) { // Simple encryption, not very strong! return Base64.encodeToString(input.getBytes(), Base64.DEFAULT); } public static String dec...

The NamedParameterJdbcTemplate class adds support for programming JDBC statements using named parameters, as opposed to programming JDBC statements using only classic placeholder ( '?') arguments. The NamedParameterJdbcTemplate class wraps a JdbcTemplate, and delegates to the wrapped JdbcTempl...