Tutorial by Examples: le

A tuple is a fixed length ordered sequence of other Erlang terms. Each element in the tuple can be any type of term (any data type). 1> {1, 2, 3}. {1,2,3} 2> {one, two, three}. {one,two,three} 3> {mix, atom, 123, {<<1,2>>, [list]}}. {mix,atom,123,{<<1,2>>,[list...

Migrations in a Laravel 5 application live in the database/migrations directory. Their filenames conform to a particular format: <year>_<month>_<day>_<hour><minute><second>_<name>.php One migration file should represent a schema update to solve a particu...

Creating a new migration file with the correct filename every time you need to change your schema would be a chore. Thankfully, Laravel's artisan command can generate the migration for you: php artisan make:migration add_last_logged_in_to_users_table You can also use the --table and --create fla...

.rds and .Rdata (also known as .rda) files can be used to store R objects in a format native to R. There are multiple advantages of saving this way when contrasted with non-native storage approaches, e.g. write.table: It is faster to restore the data to R It keeps R specific information encoded ...

We are going to be showing how to make a GET request to an API that responds with a JSON object or a JSON array. The first thing we need to do is add the Retrofit and GSON Converter dependencies to our module's gradle file. Add the dependencies for retrofit library as described in the Remarks secti...

Run-length encoding captures the lengths of runs of consecutive elements in a vector. Consider an example vector: dat <- c(1, 2, 2, 2, 3, 1, 4, 4, 1, 1) The rle function extracts each run and its length: r <- rle(dat) r # Run Length Encoding # lengths: int [1:6] 1 3 1 1 2 2 # valu...

One of the first questions people have when they begin to use PowerShell for scripting is how to manipulate the output from a cmdlet to perform another action. The pipeline symbol | is used at the end of a cmdlet to take the data it exports and feed it to the next cmdlet. A simple example is using...

Ansible maintains a PPA repository that can be used to install the Ansible binaries: sudo apt-add-repository ppa:ansible/ansible -y sudo apt-get update && sudo apt-get install ansible -y To install a specific version, use pip. The PPA may be out of date.

There are two main ways way to install Ansible on OS X, either using the Homebrew or Pip package manager. If you have homebrew, the latest Ansible can be installed using the following command: brew install ansible To install Ansible 1.9.X branch use following command: brew install homebrew/ver...

The virtualenvwrapper utility simplifies working with virtual environments and is especially useful if you are dealing with many virtual environments/projects. Instead of having to deal with the virtual environment directories yourself, virtualenvwrapper manages them for you, by storing all virtual...

The OR (||) operator returns true if one of its two operands evaluates to true, otherwise it returns false. For example, the following code evaluates to true because at least one of the expressions either side of the OR operator is true: if (10 < 20) || (20 < 10) { print("Expression...

When Fortran was originally developed memory was at a premium. Variables and procedure names could have a maximum of 6 characters, and variables were often implicitly typed. This means that the first letter of the variable name determines its type. variables beginning with i, j, ..., n are intege...

MKLocalSearch allows users to search for location using natural language strings like "gym". Once the search get completed, the class returns a list of locations within a specified region that match the search string. Search results are in form of MKMapItem within MKLocalSearchResponse ob...

Module is a collection of type declarations, data declarations and procedures. The basic syntax is: module module_name use other_module_being_used ! The use of implicit none here will set it for the scope of the module. ! Therefore, it is not required (although considered good practice...

The MATLAB Profiler is a tool for software profiling of MATLAB code. Using the Profiler, it is possible to obtain a visual representation of both execution time and memory consumption. Running the Profiler can be done in two ways: Clicking the "Run and Time" button in the MATLAB GUI...

Python 3.x3.3 Use yield from if you want to yield all values from another iterable: def foob(x): yield from range(x * 2) yield from range(2) list(foob(5)) # [0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 0, 1] This works with generators as well. def fibto(n): a, b = 1, 1 while True: ...

The following code is for iOS 8 and lower for creating a login alert. // Create the UIAlertView var loginAlertView = new UIAlertView(title, message, null, cancelTitle, okTitle); // Setting the AlertViewStyle to UIAlertViewStyle.LoginAndPasswordInput loginAlertView.AlertViewStyle = UIAlertViewS...

The module cmath includes additional functions to use complex numbers. import cmath This module can calculate the phase of a complex number, in radians: z = 2+3j # A complex number cmath.phase(z) # 0.982793723247329 It allows the conversion between the cartesian (rectangular) and polar repr...

Python has built-in support for complex arithmetic. The imaginary unit is denoted by j: z = 2+3j # A complex number w = 1-7j # Another complex number Complex numbers can be summed, subtracted, multiplied, divided and exponentiated: z + w # (3-4j) z - w # (1+10j) z * w # (23-11j) z / w # (...

function Invoke-MyCmdlet { [CmdletBinding(SupportsShouldProcess = $true)] param() # ... }