Tutorial by Examples: 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...

This a basic example aimed at new users. It does not focus on explaining the difference between char and cellstring. It might happen that you want to get rid of the ' in your strings, although you never added them. In fact, those are artifacts that the command window uses to distinguish between ...

Option Explicit Sub LoopAllSheets() Dim sht As Excel.Worksheet ' declare an array of type String without committing to maximum number of members Dim sht_Name() As String Dim i As Integer ' get the number of worksheets in Active Workbook , and put it as the maximum number of members in t...

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

if ($PSCmdlet.ShouldProcess("Target of action")) { # Do the thing } When using -WhatIf: What if: Performing the action "Invoke-MyCmdlet" on target "Target of action" When using -Confirm: Are you sure you want to perform this action? Performing operation &qu...

5.0 In PowerShell 5.0+ you can list available constructors by calling the static new-method without parentheses. PS> [DateTime]::new OverloadDefinitions ------------------- datetime new(long ticks) datetime new(long ticks, System.DateTimeKind kind) datetime new(int year, int month, int d...

class Person { [string] $Name [int] $Age Person([string] $Name) { $this.Name = $Name } Person([string] $Name, [int]$Age) { $this.Name = $Name $this.Age = $Age } }

Declaration-site variance can be thought of as declaration of use-site variance once and for all the use-sites. class Consumer<in T> { fun consume(t: T) { ... } } fun charSequencesConsumer() : Consumer<CharSequence>() = ... val stringConsumer : Consumer<String> = cha...

--- trim: a string-trimming module for Lua -- Author, date, perhaps a nice license too -- -- The code here is taken or adapted from material in -- Programming in Lua, 3rd ed., Roberto Ierusalimschy -- trim_all(string) => return string with white space trimmed on both sides local trim_al...

-- The following assumes that trim module is installed or in the caller's package.path, -- which is a built-in variable that Lua uses to determine where to look for modules. local trim = require "trim" local msg = " Hello, world! " local cleaned = trim.trim_all(msg)...

Microsoft Windows applications are usually written as either a console application or a windowed application (there are other types such as services and plug-ins). The difference for the programmer is the difference in the interface for the main entry point for the application source provided by the...

MSBuild 2015 On Windows there are three choices to get MSBuild: Install Visual Studio 2015 Download Microsoft Build Tools which includes VB and C# compilers. Build from Source On Linux Build from Source using this guide

Reading a file line by line public class Main { public static void main(String[] args) { try { Scanner scanner = new Scanner(new File("example.txt")); while(scanner.hasNextLine()) { String line = scanner.nextLine(); ...

The data.table package provides a convenient way to group by runs in data. Consider the following example data: library(data.table) (DT <- data.table(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 ...

1) scikit learn scikit-learn is a Python module for machine learning built on top of SciPy and distributed under the 3-Clause BSD license. It features various classification, regression and clustering algorithms including support vector machines, random forests, gradient boosting, k-means and DBSCA...

DT[where, select|update|do, by] syntax is used to work with columns of a data.table. The "where" part is the i argument The "select|update|do" part is the j argument These two arguments are usually passed by position instead of by name. Our example data below is mtcars =...