Tutorial by Examples: t

There might be times where you have a data frame and you want to remove all the rows that might contain an NA value, for that the function complete.cases is the best option. We will use the first 6 rows of the airquality dataset to make an example since it already has NAs x <- head(airquality) ...

A constant expression is an expression that yields a primitive type or a String, and whose value can be evaluated at compile time to a literal. The expression must evaluate without throwing an exception, and it must be composed of only the following: Primitive and String literals. Type ca...

ll | grep ^- | awk -F"." '{print $2 "." $3}' | awk -F":" '{print $2}' | awk '{$1=""; print $0}' | cut -c2- | awk -F"." '{print "mkdir ""$1"";mv ""$1"."$2"" ""$1"""}' >...

In Apache Spark while doing shuffle operations like join and cogroup a lot of data gets transferred across network. Now, to control the number of partitions over which shuffle happens can be controlled by configurations given in Spark SQL. That configuration is as follows: spark.sql.shuffle.partiti...

Java expressions are evaluated following the following rules: Operands are evaluated from left to right. The operands of an operator are evaluated before the operator. Operators are evaluated according to operator precedence Argument lists are evaluated from left to right. Simple Example I...

git filter-branch --force --index-filter \ 'git rm --cached --ignore-unmatch PATH-TO-YOUR-FILE-WITH-SENSITIVE-DATA' \ --prune-empty --tag-name-filter cat -- --all Add your file with sensitive data to .gitignore to ensure that you don't accidentally commit it again. echo "YOUR-FILE-WITH-SE...

BFG Repo cleaner is an alternative to git filter-branch. It can be used to remove sensitive data or large files that were committed wrongly like binaries compiled from the source. It is written in Scala. Project website: BFG Repo Cleaner Requirements The Java Runtime Environment (Java 7 or above ...

Objects become eligible for garbage collection (GC) if they are no longer reachable by the main entry point(s) in a program. GC is usually not performed explicitly by the user, but to let the GC know an object is no longer needed a developer can: Dereference / assign null someFunction { var ...

When interfacing with C APIs, one might want to back off Swift reference counter. Doing so is achieved with unmanaged objects. If you need to supply a type-punned pointer to a C function, use toOpaque method of the Unmanaged structure to obtain a raw pointer, and fromOpaque to recover the original ...

; IF d0 == 10 GO TO ten, ELSE GO TO other CMP #10,d0 ; compare register contents to immediate value 10 ; instruction affects the zero flag BEQ ten ; branch if zero flag set other: ; do whatever needs to be done for d0 != 10 BRA ...

The Z80 has a specific instruction to implement loop counts: DJNZstanding for "decrement B register and jump if not zero". So, B is the register of choice to implement loops on this processor. FOR...NEXT needs to be implemented "backwards", because the register counts down to zer...

SampleViewModel.vb 'Import classes related to WPF for simplicity Imports System.Collections.ObjectModel Imports System.ComponentModel Public Class SampleViewModel Inherits DependencyObject 'A class acting as a ViewModel must inherit from DependencyObject 'A simple string p...

self.view.backgroundColor = [UIColor colorWithPatternImage:[UIImage imageNamed:@"Background.png"]];

1- Define Your own custom Block typedef void(^myCustomCompletion)(BOOL); 2- Create custom method which takes your custom completion block as a parameter. -(void) customMethodName:(myCustomCompletion) compblock{ //do stuff // check if completion block exist; if we do not check it will ...

React components that are pure functions of their props and do not require any internal state can be written as JavaScript functions instead of using the standard class syntax, as: import React from 'react' const HelloWorld = (props) => ( <h1>Hello, {props.name}!</h1> ); ...

To use typescript with react in a node project, you must first have a project directory initialized with npm. To initialize the directory with npm init Installing via npm or yarn You can install React using npm by doing the following: npm install --save react react-dom Facebook released its ow...

The simplest react component without a state and no properties can be written as: import * as React from 'react'; const Greeter = () => <span>Hello, World!</span> That component, however, can't access this.props since typescript can't tell if it is a react component. To access ...

VueJS can be used to easily handle user input as well, and the two way binding using v-model makes it really easy to change data easily. HTML : <script src="https://unpkg.com/vue/dist/vue.js"></script> <div id="app"> {{message}} <input v-model="...

In case you have json with an ISO date string like this JSON.stringify({date: new Date()}) // -> "{"date":"2016-12-12T13:24:34.470Z"}" You can map it to elm Date type: import Html exposing (text) import Json.Decode as JD import Date payload = ""&...

Campaign Monitor built a nifty tool that generates code for buttons in HTML email. It uses a cominbation os CSS and VML (for Microsoft Outlook) to display background images or patterns in most major email clients. <div><!--[if mso]> <v:roundrect xmlns:v="urn:schemas-microsoft...