Tutorial by Examples: l

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...

Sometimes a column should show different content than just the toString value of the cell item. In this case the TableCells created by the cellFactory of the TableColumn is customized to change the layout based on the item. Important Note: TableView only creates the TableCells that are shown in the...

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 ...

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...

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...

Metaclass syntax Python 2.x2.7 class MyClass(object): __metaclass__ = SomeMetaclass Python 3.x3.0 class MyClass(metaclass=SomeMetaclass): pass Python 2 and 3 compatibility with six import six class MyClass(six.with_metaclass(SomeMetaclass)): pass

Ubuntu On recent Ubuntu versions, you can install an up-to-date version of CouchDB with sudo apt-get install couchdb. For older versions, such as Ubuntu 14.04, you should run: sudo add-apt-repository ppa:couchdb/stable -y sudo apt-get update sudo apt-get install couchdb -y Fedora To install ...

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...

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

<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 ...

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.

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...

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...

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...

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

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;

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...

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 ...

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

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