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 = "...
The canvas element was introduced in HTML5 for drawing graphics.
<canvas id="myCanvas">
Cannot display graphic. Canvas is not supported by your browser (IE<9)
</canvas>
The above will create a transparent HTML<canvas> element of 300×150 px in size.
You can us...
The family of x86 assembly languages represents decades of advances on the original Intel 8086 architecture. In addition to there being several different dialects based on the assembler used, additional processor instructions, registers and other features have been added over the years while still r...
Angular2 comes with a few built-in pipes:
PipeUsageExampleDatePipedate{{ dateObj | date }} // output is 'Jun 15, 2015'UpperCasePipeuppercase{{ value | uppercase }} // output is 'SOMETEXT'LowerCasePipelowercase{{ value | lowercase }} // output is 'sometext'CurrencyPipecurrency{{ 31.00 | currency:'US...
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...
std::enable_if is a convenient utility to use boolean conditions to trigger SFINAE. It is defined as:
template <bool Cond, typename Result=void>
struct enable_if { };
template <typename Result>
struct enable_if<true, Result> {
using type = Result;
};
That is, enable_...
The break keyword can be used in switch statements to exit the statement before evaluating all conditions.
Example:
switch('Condition')
{
'Condition'
{
'First Action'
}
'Condition'
{
'Second Action'
break
}
'Condition'
{
'Third Action'
}
}
Output...
Fixnum#to_s takes an optional base argument and represents the given number in that base:
2.to_s(2) # => "10"
3.to_s(2) # => "11"
3.to_s(3) # => "10"
10.to_s(16) # => "a"
If no argument is provided, then it represents the number in bas...
It is common for memory performance to compress multiple values into a single primitive value.
This may be useful to pass various information into a single variable.
For example, one can pack 3 bytes - such as color code in RGB - into an single int.
Packing the values
// Raw bytes as input
byte...
The SQL 2008 standard defines the FETCH FIRST clause to limit the number of records returned.
SELECT Id, ProductName, UnitPrice, Package
FROM Product
ORDER BY UnitPrice DESC
FETCH FIRST 10 ROWS ONLY
This standard is only supported in recent versions of some RDMSs. Vendor-specific non-stand...
Pojo Model
public class Model {
private String firstName;
private String lastName;
private int age;
/* Getters and setters not shown for brevity */
}
Example: String to Object
Model outputObject = objectMapper.readValue(
"{\"firstName\":\"J...
It's possible to attach an object to an existing object as if there was a new property. This is called association and allows one to extend existing objects. It can be used to provide storage when adding a property via a class extension or otherwise add additional information to an existing object.
...
HTML5 data-* attributes provide a convenient way to store data in HTML elements. The stored data can be read or modified using JavaScript
<div data-submitted="yes" class="user_profile">
… some content …
</div>
Data attribute structure is data-*, i.e. the n...
You can use the <img> or <object> elements to embed external SVG elements. Setting the height and width is optional but is highly recommended.
Using the image element
<img src="attention.svg" width="50" height="50">
Using <img> does not allo...
You can add external SVG files using the background-image property, just as you would do with any other image.
HTML:
<div class="attention"></div>
CSS:
.attention {
background-image: url(attention.svg);
background-size: 100% 100%;
width: 50px;
height: ...
To search if a String contains a substring, do the following:
NSString *myString = @"This is for checking substrings";
NSString *subString = @"checking";
BOOL doesContainSubstring = [myString containsString:subString]; // YES
If targeting iOS 7 or OS X 10.9 (or earlier)...
typedef double (^Operation)(double first, double second);
If you declare a block type as a typedef, you can then use the new type name instead of the full description of the arguments and return values. This defines Operation as a block that takes two doubles and returns a double.
The type can b...
