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Angles are in Radians, not Degrees. All computations are done in IEEE 754 64-bit floating point. All floating point computations are subject to small errors, known as machine ε (epsilon) errors, so avoid trying to compare them for equality. There is no way to avoid these errors when using floating p...

Round a decimal number to an integer value For exact numeric values (e.g. DECIMAL): If the first decimal place of a number is 5 or higher, this function will round a number to the next integer away from zero. If that decimal place is 4 or lower, this function will round to the next integer value cl...

Mixins are a sort of class that is used to "mix in" extra properties and methods into a class. This is usually fine because many times the mixin classes don't override each other's, or the base class' methods. But if you do override methods or properties in your mixins this can lead to une...

To install and load the current stable version of ggplot2 for your R installation use: # install from CRAN install.packages("ggplot2") To install the development version from github use # install.packages("devtools") devtools::install_github("hadley/ggplot2") ...

As ES6 introduced Symbols, which are both unique and immutable primitive values that may be used as the key of an Object property, instead of using strings as possible values for an enum, it's possible to use symbols. // Simple symbol const newSymbol = Symbol(); typeof newSymbol === 'symbol' // t...

The SilverStripe CMS can be customised to change the CMS logo, link and application name. This can be achieved with the following config.yml settings LeftAndMain: application_name: 'My Application' application_link: 'http://www.example.com/' extra_requirements_css: - mysite/css/cms.c...

import java.util.Scanner; Scanner s = new Scanner(System.in); int number = s.nextInt(); If you want to read an int from the command line, just use this snippet. First of all, you have to create a Scanner object, that listens to System.in, which is by default the Command Line, when you start ...

SpriteKit functionality can be implemented in a subclass of SKScene. For example, a game may implement the main game functionality within an SKScene subclass called GameScene. In Swift: import SpriteKit class GameScene: SKScene { override func didMoveToView(view: SKView) { /* Co...

Chaining assignments as part of a var declaration will create global variables unintentionally. For example: (function foo() { var a = b = 0; })() console.log('a: ' + a); console.log('b: ' + b); Will result in: Uncaught ReferenceError: a is not defined 'b: 0' In the above examp...

Mapping Applying a function to all elements of an array : array_map('strtoupper', $array); Be aware that this is the only method of the list where the callback comes first. Reducing (or folding) Reducing an array to a single value : $sum = array_reduce($numbers, function ($carry, $number) { ...

After your service worker is registered, the browser will try to install & later activate the service worker. Install event listener this.addEventListener('install', function(event) { console.log('installed'); }); Caching One can use this install event returned to cache the assets ne...

MySQL offers a number of different numeric types. These can be broken down into GroupTypesInteger TypesINTEGER, INT, SMALLINT, TINYINT, MEDIUMINT, BIGINTFixed Point TypesDECIMAL, NUMERICFloating Point TypesFLOAT, DOUBLEBit Value TypeBIT

Minimal unsigned value is always 0. TypeStorage(Bytes)Minimum Value(Signed)Maximum Value(Signed)Maximum Value(Unsigned)TINYINT1-27-12827-112728-1255SMALLINT2-215-32,768215-132,767216-165,535MEDIUMINT3-223-8,388,608223-18,388,607224-116,777,215INT4-231-2,147,483,648231-12,147,483,647232-14,294,967,2...

MySQL's DECIMAL and NUMERIC types store exact numeric data values. It is recommended to use these types to preserve exact precision, such as for money. Decimal These values are stored in binary format. In a column declaration, the precision and scale should be specified Precision represents the n...

FLOAT and DOUBLE represent approximate data types. TypeStoragePrecisionRangeFLOAT4 bytes23 significant bits / ~7 decimal digits10^+/-38DOUBLE8 bytes53 significant bits / ~16 decimal digits10^+/-308 REAL is a synonym for FLOAT. DOUBLE PRECISION is a synonym for DOUBLE. Although MySQL also permits...

WebSocket provides a duplex/bidirectional communication protocol over a single TCP connection. the client opens a connection to a server that is listening for a WebSocket request a client connects to a server using a URI. A server may listen to requests from multiple clients. Server Endpoint...

It's best for readability (and your sanity) to avoid escaping the escapes. That's where raw strings literals come in. (Note that some languages allow delimiters, which are preferred over strings usually. But that's another section.) They usually work the same way as this answer describes: [A] ba...

In most programming languages, in order to have a backslash in a string generated from a string literal, each backslash must be doubled in the string literal. Otherwise, it will be interpreted as an escape for the next character. Unfortunately, any backslash required by the regex must be a literal ...

The easiest and quickest way to encode a Haskell data type to JSON with Aeson is using generics. {-# LANGUAGE DeriveGeneric #-} import GHC.Generics import Data.Text import Data.Aeson import Data.ByteString.Lazy First let us create a data type Person: data Person = Person { firstName :...

Detailed instructions on excel-formula(s). There are many formulas that you can choose from. They are divided up into 7 different categories and are on the FORMULAS tab in Excel. The categories are: Financial Logical Text Date & Time Lookup & Reference Math & trig More Function...