Tutorial by Examples: i

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...

type person = {Name: string; Age: int} with // Defines person record member this.print() = printfn "%s, %i" this.Name this.Age let user = {Name = "John Doe"; Age = 27} // creates a new person user.print() // John Doe, 27

type person = {Name: string; Age: int} // Defines person record let user1 = {Name = "John Doe"; Age = 27} // creates a new person let user2 = {user1 with Age = 28} // creates a copy, with different Age let user3 = {user1 with Name = "Jane Doe"; Age = 29} //creates ...

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...

Similar to rgb() notation, but with an additional alpha (opacity) value. .red { /* Opaque red */ color: rgba(255, 0, 0, 1); } .red-50p { /* Half-translucent red. */ color: rgba(255, 0, 0, .5); } Syntax rgba(<red>, <green>, <blue>, <alpha>); Va...

For setting some zoom level, let say we want to zoom user's location with user location as center and 2km of area as radius. Then, we use following code MKUserLocation *userLocation = _mapView.userLocation; MKCoordinateRegion region = MKCoordinateRegionMakeWithDistance (userLocation.location.coord...

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...

div { -webkit-transition: all 4s ease; -moz-transition: all 4s ease; -o-transition: all 4s ease; transition: all 4s ease; }

The filter or map functions should often be replaced by list comprehensions. Guido Van Rossum describes this well in an open letter in 2005: filter(P, S) is almost always written clearer as [x for x in S if P(x)], and this has the huge advantage that the most common usages involve predicates tha...

You may wish to use Model Factories within your seeds. This will create 3 new users. use App\Models\User; class UserTableSeeder extends Illuminate\Database\Seeder{ public function run(){ factory(User::class)->times(3)->create(); } } You may also want to define ...

Artisan is a utility that can help you do specific repetitive tasks with bash commands. It covers many tasks, including: working with database migrations and seeding, clearing cache, creating necessary files for Authentication setup, making new controllers, models, event classes, and a lot more. ...

The following is the original "Hello, World!" program from the book The C Programming Language by Brian Kernighan and Dennis Ritchie (Ritchie was the original developer of the C programming language at Bell Labs), referred to as "K&R": K&R #include <stdio.h> ma...

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: ...

One might want to group their data by the runs of a variable and perform some sort of analysis. Consider the following simple dataset: (dat <- data.frame(x = c(1, 1, 2, 2, 2, 1), y = 1:6)) # x y # 1 1 1 # 2 1 2 # 3 2 3 # 4 2 4 # 5 2 5 # 6 1 6 The variable x has three runs: a run of l...

Given this setup code: var dict = new Dictionary<int, string>() { { 1, "First" }, { 2, "Second" }, { 3, "Third" } }; You may want to read the value for the entry with key 1. If key doesn't exist getting a value will throw KeyNotFoundException,...

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 # (...

To install Eclipse, go to the Eclipse Downloads Web page where there is usually a direct link to download the latest version of Eclipse. Starting Eclipse Mars (version 4.5), an installer can be downloaded which guides you through the installation procedure, as opposed to downloading the whole instal...