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Elm Language • Ports (JS interop)

Keyword-only and Keyword-required arguments

Python 3 allows you to define function arguments which can only be assigned by keyword, even without default values. This is done by using star * to consume additional positional parameters without setting the keyword parameters. All arguments after the * are keyword-only (i.e. non-positional) arg...

Python Language • *args and **kwargs

Convert all columns of a data.frame to character class

A common task is to convert all columns of a data.frame to character class for ease of manipulation, such as in the cases of sending data.frames to a RDBMS or merging data.frames containing factors where levels may differ between input data.frames. The best time to do this is when the data is read ...

R Language • Data frames

Rational Numbers

Rational represents a rational number as numerator and denominator: r1 = Rational(2, 3) r2 = 2.5.to_r r3 = r1 + r2 r3.numerator # => 19 r3.denominator # => 6 Rational(2, 4) # => (1/2) Other ways of creating a Rational Rational('2/3') # => (2/3) Rational(3) # => (3/1...

Ruby Language • Numbers

Complex Numbers

1i # => (0+1i) 1.to_c # => (1+0i) rectangular = Complex(2, 3) # => (2+3i) polar = Complex('1@2') # => (-0.4161468365471424+0.9092974268256817i) polar.rectangular # => [-0.4161468365471424, 0.9092974268256817] rectangular.polar # => [3.605551275463989, 0.9827937232...

Ruby Language • Numbers

Block DO construct

A do construct is a looping construct which has a number of iterations governed by a loop control integer i do i=1, 5 print *, i end do print *, i In the form above, the loop variable i passes through the loop 5 times, taking the values 1 to 5 in turn. After the construct has completed th...

Fortran • Execution Control

Looping through a collection using CFML tags.

<cfset attributes = { "name": "Sales", "type": "text", "value": "Connection" }> <!--- cfloop tag with attribute collection can be used to loop through the elements of a struc...

coldfusion • CFLOOP How-To

Looping through a collection using CFSCRIPT.

<cfscript> /*define collection*/ attributes = { "name": "Sales", "type": "text", "value": "Connection" }; for(attribute in attributes){ /* attribute variable will contain the key name of each key value ...

coldfusion • CFLOOP How-To

Queue Driver Configuration

Each of Laravel's queue drivers are configured from the config/queue.php file. A queue driver is the handler for managing how to run a queued job, identifying whether the jobs succeeded or failed, and trying the job again if configured to do so. Out of the box, Laravel supports the following queue ...

Laravel • Queues

Setting parameters for PreparedStatement

Placeholders in the query string need to be set by using the set* methods: String sql = "SELECT * FROM EMP WHERE JOB = ? AND SAL > ?"; //Create statement to make your operations PreparedStatement statement = connection.prepareStatement(sql); statement.setString(1, "MANAGER&...

jdbc • PreparedStatement

Installation or Setup

SQL Server Reporting Services can typically be installed with SQL Server installation media. An installation of SQL Server will be required, either locally or on a server. Starting with SQL Server 2008 R2, SSRS has the option to integrate with SharePoint instead of running a separate website.

reporting-services • Getting started with reporting-services

Simple Dual Port RAM

Simple Dual Port RAM with separate addresses and clocks for read/write operations. module simple_ram_dual_clock #( parameter DATA_WIDTH=8, //width of data bus parameter ADDR_WIDTH=8 //width of addresses buses )( input [DATA_WIDTH-1:0] data, //da...

verilog • Memories

Simple Mouse Event Structure

Through the use of event types you can easily reduce code bloat that often occurs when defining events for many objects on stage by filtering events in 1 function rather than defining many event handling functions. Imagine we have 10 objects on stage named object1, object2 ... object10 You could d...

ActionScript 3 • Working with Events

Validating User Account On Publish

Sometimes it's a good idea to further secure your publishes by requiring a user login. Here is how you achieve this via Meteor. import { Recipes } from '../imports/api/recipes.js'; import { Meteor } from 'meteor/meteor'; Meteor.publish('recipes', function() { if(this.userId) { return Re...

meteor • Publishing Data

int literals

int literals are defined by simply using integral values within the range of int: int i = 5;

C# Language • Literals

uint literals

uint literals are defined by using the suffix U or u, or by using an integral values within the range of uint: uint ui = 5U;

C# Language • Literals

string literals

string literals are defined by wrapping the value with double-quotes ": string s = "hello, this is a string literal"; String literals may contain escape sequences. See String Escape Sequences Additionally, C# supports verbatim string literals (See Verbatim Strings). These are def...

C# Language • Literals

char literals

char literals are defined by wrapping the value with single-quotes ': char c = 'h'; Character literals may contain escape sequences. See String Escape Sequences A character literal must be exactly one character long (after all escape sequences have been evaluated). Empty character literals are ...

C# Language • Literals

byte literals

byte type has no literal suffix. Integer literals are implicitly converted from int: byte b = 127;

C# Language • Literals

sbyte literals

sbyte type has no literal suffix. Integer literals are implicitly converted from int: sbyte sb = 127;

C# Language • Literals