Tutorial by Examples: ar

In C, character constants and string literals are different things. A character surrounded by single quotes like 'a' is a character constant. A character constant is an integer whose value is the character code that stands for the character. How to interpret character constants with multiple charac...

To know the path of the directory your file is in you can use: Esc to enter command mode :pwd This will print the path to the directory at the bottom of the editor, like this I'm a ninja ~ ~ ~ ~ ~ /home/ubuntu/myfolder 1,5 All Now...

Singleton classes share their instance/class variables with their object. class Example @@foo = :example end def Example.foo class_variable_get :@@foo end Example.foo #=> :example class Example def initialize @foo = 1 end def foo @foo end end e = Ex...

In Normal, type the following to delete a range of lines into a named register :10,20d a This will delete lines 10,20 in register "a. We can verify this by typing :reg This will show the text that was delete in register "a. To paste the contents in "a, just type "ap ...

Prerequisites Create a new project and add an iOS app to that project in the Firebase Console. Download and include GoogleServices-Info.plist in your application. Add Firebase Storage to your app Add the following dependency to your project's Podfile: pod 'Firebase/Storage' Run pod insta...

In functions, you can define a number of mandatory arguments: def fun1(arg1, arg2, arg3): return (arg1,arg2,arg3) which will make the function callable only when the three arguments are given: fun1(1, 2, 3) and you can define the arguments as optional, by using default values: def fun...

When you want to create a function that can accept any number of arguments, and not enforce the position or the name of the argument at "compile" time, it's possible and here's how: def fun1(*args, **kwargs): print(args, kwargs) The *args and **kwargs parameters are special parame...

Since Laravel version 5.2.31 the web middleware is applied by default within the RouteServiceProvider (https://github.com/laravel/laravel/commit/5c30c98db96459b4cc878d085490e4677b0b67ed) In app/Providers/RouteServiceProvider.php you will find the following functions which apply the middleware on ev...

The target attribute specifies a name or a keyword that indicates where to display the response that is received after submitting the form. The target attribute defines a name of, or keyword for, a browsing context (e.g. tab, window, or inline frame). From Tag with a target attribute: <form ta...

private final OkHttpClient client = new OkHttpClient(); public void run() throws Exception { RequestBody formBody = new FormBody.Builder() .add("search", "Jurassic Park") .build(); Request request = new Request.Builder() .url("https:...

private static final String IMGUR_CLIENT_ID = "..."; private static final MediaType MEDIA_TYPE_PNG = MediaType.parse("image/png"); private final OkHttpClient client = new OkHttpClient(); public void run() throws Exception { // Use the imgur image upload API as ...

2.12.2 You can use the minElement() and maxElement() methods to find the minimum or maximum element in a given sequence. For example, with an array of numbers: let numbers = [2, 6, 1, 25, 13, 7, 9] let minimumNumber = numbers.minElement() // Optional(1) let maximumNumber = numbers.maxElement()...

Often beginning MATLAB developers will use MATLAB's editor to write and edit code, in particular custom functions with inputs and outputs. There is a Run button at the top that is available in recent versions of MATLAB: Once the developer finishes with the code, they are often tempted to push th...

If you're just getting started with Chef, we recommend starting off with our Learn Chef tutorial at http://learn.chef.io/. If you have questions during or after that, check out or discussion forum/mailing list at https://discourse.chef.io/ or our public Slack team at https://community-slack.chef.io...

These are the datepart values available to date & time functions: datepartAbbreviationsyearyy, yyyyquarterqq, qmonthmm, mdayofyeardy, ydaydd, dweekwk, wwweekdaydw, whourhhminutemi, nsecondss, smillisecondmsmicrosecondmcsnanosecondns NOTE: Use of abbreviations is generally discouraged as they c...

DATEPART returns the specified datepart of the specified datetime expression as a numeric value. DATENAME returns a character string that represents the specified datepart of the specified date. In practice DATENAME is mostly useful for getting the name of the month or the day of the week. There a...

A CSS rule consists of a selector (e.g. h1) and declaration block ({}). h1 {}

The most basic instance of an if construct evaluates a condition and executes some code according to the condition outcome. If the condition returns true, the code within the conditional is executed. counter = 10 if counter is 10 console.log 'This will be executed!' The if construct can be e...

An array column is supported by PostgreSQL. Rails will automatically convert a PostgreSQL array to a Ruby array, and vice-versa. Create a table with an array column: create_table :products do |t| t.string :name t.text :colors, array: true, default: [] end Add an array column to an existi...

Unzipping a zip archive is done with unzip function from the utils package (which is included in base R). unzip(zipfile = "bar.zip", exdir = "./foo") This will extract all files in "bar.zip" to the "foo" directory, which will be created if necessary. Tilde...