Tutorial by Examples: num

When expecting someone to reproduce an R code that has random elements in it, the set.seed() function becomes very handy. For example, these two lines will always produce different output (because that is the whole point of random number generators): > sample(1:10,5) [1] 6 9 2 7 10 >...

If your enum class is required to have static fields, keep in mind they are created after the enum values themselves. That means, the following code will result in a NullPointerException: enum Example { ONE(1), TWO(2); static Map<String, Integer> integers = new HashMap<>(); ...

This can be easily accomplished by calling Enumerable#to_a on a Range object: (1..10).to_a #=> [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] (a..b) means that it will include all numbers between a and b. To exclude the last number, use a...b a_range = 1...5 a_range.to_a #=> [1, 2, 3, 4] or...

The normal way to create an array of numbers: numbers = [1, 2, 3, 4, 5] Range objects can be used extensively to create an array of numbers: numbers = Array(1..10) # => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] numbers = (1..10).to_a # => [1, 2, 3, 4, 5, 6, 7, 8, 9, 10] #step and #map methods...

import std.stdio; bool isPrime(int number) { foreach(i; 2..number) { if (number % i == 0) { return false; } } return true; } void main() { writeln(2.isPrime); writeln(3.isPrime); writeln(4.isPrime); 5.isPrime.writeln; } ...

FNR contains the number of the input file row being processed. In this example you will see awk starting on 1 again when starting to process the second file. Example with one file $ cat file1 AAAA BBBB CCCC $ awk '{ print FNR }' file1 1 2 3 Example with two files $ cat file1 AAAA BBBB...

As of IntelliJ IDEA version 2016.2, and IdeaVim version 0.46, IntelliJ's native option for showing line numbers is ineffective. When clicking Show line numbers, the line numbers immediately show and disappear. This problem is caused by a bug in the IdeaVim plugin, which can be resolved by using the...

Specific for <li> tags within an unordered list (<ul>): list-style: disc; /* A filled circle (default) */ list-style: circle; /* A hollow circle */ list-style: square; /* A filled square */ list-style: '-'; /* any string */ ...

After defining an enum using any of the above ways and setting a variable, you can print both the variable's value as well as the corresponding name from the enum for the value. Here's an example: // Define the enum var ColorsEnum = { WHITE: 0, GRAY: 1, BLACK: 2 } Object.freeze(ColorsEnum); // D...

An HTTP POST request is sent to a URL of the format: "https://api.twilio.com/2xxx-xx-xx/Accounts/[AccountSid]/Messages.json The example below uses a alphanumeric string as the sender. At the time of writing a sender ID can only be added through a service request Twlio. Example Request: To=&q...

A common use-case for iterators is to perform some operation over a collection of numbers. The example below demonstrates how each element within an array of numbers can be individually printed out to the console. This is possible because arrays implement the IEnumerable interface, allowing clients...

When working with large files, you can use the System.IO.File.ReadLines method to read all lines from a file into an IEnumerable<string>. This is similar to System.IO.File.ReadAllLines, except that it doesn't load the whole file into memory at once, making it more efficient when working with l...

Ada 2012(TC-1) with Ada.Text_IO; procedure Main is type Fruit is (Banana, Orange, Pear); X : Fruit := Orange; begin Ada.Text_IO.Put_Line (X'Image); Ada.Text_IO.Put_Line (Pear'Image); end Main; Result ORANGE PEAR

with Ada.Text_IO; procedure Main is type Fruit is (Banana, Orange, Pear); X : Fruit := Orange; begin Ada.Text_IO.Put_Line (Fruit'Image (X)); end Main; Result ORANGE

For immutable elements (e.g. None, string literals etc.): my_list = [None] * 10 my_list = ['test'] * 10 For mutable elements, the same construct will result in all elements of the list referring to the same object, for example, for a set: >>> my_list=[{1}] * 10 >>> print(my_...

In C++, a byte is the space occupied by a char object. The number of bits in a byte is given by CHAR_BIT, which is defined in climits and required to be at least 8. While most modern systems have 8-bit bytes, and POSIX requires CHAR_BIT to be exactly 8, there are some systems where CHAR_BIT is great...

One of the great things about Linq is that it is so easy to extend. You just need to create an extension method whose argument is IEnumerable<T>. public namespace MyNamespace { public static class LinqExtensions { public static IEnumerable<List<T>> Batch<T&...

ENUM provides a way to provide an attribute for a row. Attributes with a small number of non-numeric options work best. Examples: reply ENUM('yes', 'no') gender ENUM('male', 'female', 'other', 'decline-to-state') The values are strings: INSERT ... VALUES ('yes', 'female') SELECT ... --> ...

Enums are defined by the following the syntax above. typedef NS_ENUM(NSUInteger, MyEnum) { MyEnumValueA, MyEnumValueB, MyEnumValueC, }; You also can set your own raw-values to the enumeration types. typedef NS_ENUM(NSUInteger, MyEnum) { MyEnumValueA = 0, MyEnumValueB =...

The example below will collect the Device's OS version number and the the version of the application (which is defined in each projects' properties) that is entered into Version name on Android and Version on iOS. First make an interface in your PCL project: public interface INativeHelper { /...