Tutorial by Examples: d

Getting the string representation of a Guid

A string representation of a Guid can be obtained by using the built in ToString method string myGuidString = myGuid.ToString(); Depending on your needs you can also format the Guid, by adding a format type argument to the ToString call. var guid = new Guid("7febf16f-651b-43b0-a5e3-0da8da4...

C# Language • Guid

Most Common Real Life Key Value Coding Example

Key Value Coding is integrated into NSObject using NSKeyValueCoding protocol. What this means? It means that any id object is capable of calling valueForKey method and its various variants like valueForKeyPath etc. ' It also means that any id object can invoke setValue method and its various vari...

Objective-C Language • Key Value Coding / Key Value Observing

clone() method

The clone() method is used to create and return a copy of an object. This method arguable should be avoided as it is problematic and a copy constructor or some other approach for copying should be used in favour of clone(). For the method to be used all classes calling the method must implement the...

Java Language • Object Class Methods and Constructor

Reducing the Capacity of a Vector

A std::vector automatically increases its capacity upon insertion as needed, but it never reduces its capacity after element removal. // Initialize a vector with 100 elements std::vector<int> v(100); // The vector's capacity is always at least as large as its size auto const old_capacity...

C++ • std::vector

Declaring a property

At its simplest, a property is a function which returns a Bool. prop_reverseDoesNotChangeLength xs = length (reverse xs) == length xs A property declares a high-level invariant of a program. The QuickCheck test runner will evaluate the function with 100 random inputs and check that the result is...

Haskell Language • QuickCheck

Dynamic class creation

Classes can be created dynamically through the use of Class.new. # create a new class dynamically MyClass = Class.new # instantiate an object of type MyClass my_class = MyClass.new In the above example, a new class is created and assigned to the constant MyClass. This class can be instanti...

Ruby Language • Classes

Joining Strings with a delimiter

Java SE 8 An array of strings can be joined using the static method String.join(): String[] elements = { "foo", "bar", "foobar" }; String singleString = String.join(" + ", elements); System.out.println(singleString); // Prints "foo + bar + foobar&qu...

Java Language • Strings

Current Date and Time

R is able to access the current date, time and time zone: Sys.Date() # Returns date as a Date object ## [1] "2016-07-21" Sys.time() # Returns date & time at current locale as a POSIXct object ## [1] "2016-07-21 10:04:39 CDT" as.numeric(Sys...

R Language • Date and Time

Formatting Dates

To format Dates we use the format(date, format="%Y-%m-%d") function with either the POSIXct (given from as.POSIXct()) or POSIXlt (given from as.POSIXlt()) d = as.Date("2016-07-21") # Current Date Time Stamp format(d,"%a") # Abbreviated Weekday ## [1] &qu...

R Language • The Date class

Formatting and printing date-time objects

# test date-time object options(digits.secs = 3) d = as.POSIXct("2016-08-30 14:18:30.58", tz = "UTC") format(d,"%S") # 00-61 Second as integer ## [1] "30" format(d,"%OS") # 00-60.99… Second as fractional ## [1] "30.579" for...

R Language • Date-time classes (POSIXct and POSIXlt)

Parsing strings into date-time objects

The functions for parsing a string into POSIXct and POSIXlt take similar parameters and return a similar-looking result, but there are differences in how that date-time is stored; see "Remarks." as.POSIXct("11:38", # time string format = "...

R Language • Date-time classes (POSIXct and POSIXlt)

Getting Started: Hello world!

Creating an HTML document and enabling knockout.js Create an HTML file and include knockout.js via a <script> tag. <!DOCTYPE html> <html> <head> <title>Hello world! (knockout.js)</title> </head> <body> <script src="https://cdnjs...

knockout.js • Getting started with knockout.js

First Module and Hello World

To start coding in the first place, you have to right click your VBA Project in the left list and add a new Module. Your first Hello-World Code could look like this: Sub HelloWorld() MsgBox "Hello, World!" End Sub To test it, hit the Play-Button in your Toolbar or simply hit the...

VBA • Getting started with VBA

Add shadows to text

Swift label1.layer.shadowOffset = CGSize(width: 3, height: 3) label1.layer.shadowOpacity = 0.7 label1.layer.shadowRadius = 2 Swift 3 label1.layer.shadowOffset = CGSize(width: 3, height: 3) label1.layer.shadowOpacity = 0.7 label1.layer.shadowRadius = 2 Objective-C label1.layer.shadowOffs...

iOS • UILabel

INSERT multiple rows of data

To insert multiple rows of data in SQL Server 2008 or later: INSERT INTO USERS VALUES (2, 'Michael', 'Blythe'), (3, 'Linda', 'Mitchell'), (4, 'Jillian', 'Carson'), (5, 'Garrett', 'Vargas'); To insert multiple rows of data in earlier versions of SQL Server, use "UNION ALL" like so: ...

Microsoft SQL Server • INSERT INTO

INSERT a single row of data

A single row of data can be inserted in two ways: INSERT INTO USERS(Id, FirstName, LastName) VALUES (1, 'Mike', 'Jones'); Or INSERT INTO USERS VALUES (1, 'Mike', 'Jones'); Note that the second insert statement only allows the values in exactly the same order as the table columns whereas in...

Microsoft SQL Server • INSERT INTO

DECIMAL and NUMERIC

Fixed precision and scale decimal numbers. DECIMAL and NUMERIC are functionally equivalent. Syntax: DECIMAL ( precision [ , scale] ) NUMERIC ( precision [ , scale] ) Examples: SELECT CAST(123 AS DECIMAL(5,2)) --returns 123.00 SELECT CAST(12345.12 AS NUMERIC(10,5)) --returns 12345.12000

SQL • Data Types

FLOAT and REAL

Approximate-number data types for use with floating point numeric data. SELECT CAST( PI() AS FLOAT) --returns 3.14159265358979 SELECT CAST( PI() AS REAL) --returns 3.141593

SQL • Data Types

MONEY and SMALLMONEY

Data types that represent monetary or currency values. Data typeRangeStoragemoney-922,337,203,685,477.5808 to 922,337,203,685,477.58078 bytessmallmoney-214,748.3648 to 214,748.36474 bytes

SQL • Data Types

BINARY and VARBINARY

Binary data types of either fixed length or variable length. Syntax: BINARY [ ( n_bytes ) ] VARBINARY [ ( n_bytes | max ) ] n_bytes can be any number from 1 to 8000 bytes. max indicates that the maximum storage space is 2^31-1. Examples: SELECT CAST(12345 AS BINARY(10)) -- 0x0000000000000000...

SQL • Data Types