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A default constructor is a type of constructor that requires no parameters when called. It is named after the type it constructs and is a member function of it (as all constructors are). class C{ int i; public: // the default constructor definition C() : i(0){ // member initial...

Subscripts can also be used with NSDictionary and NSMutableDictionary. The following code: NSMutableDictionary *myDictionary = [@{@"Foo": @"Bar"} mutableCopy]; [myDictionary setObject:@"Baz" forKey:@"Foo"]; NSLog(@"%@", [myDictionary objectForKey:...

In PCRE, matched groups used for backreferences before a recursion are kept in the recursion. But after the recursion they all reset to what they were before entering it. In other words, matched groups in the recursion are all forgotten. For example: (?J)(?(DEFINE)(\g{a}(?<a>b)\g{a}))(?<a...

In PCRE, it doesn't trackback after the first match for a recursion is found. So (?(DEFINE)(aaa|aa|a))(?1)ab doesn't match aab because after it matched aa in the recursion, it never try again to match only a.

Prerequisite steps: Install Java at your machine Visit neo4j website and click the link "Download Community Edition" or visit directly the download link. Unzip the .tar downloaded file in your home directory Start Neo4j from console (headless, without web server) Visit the sub-d...

Quite often you have a file which was edited within DOS or Windows and you are viewing it under UNIX. This can look like the following when you view the file with vi. First line of file^M Next Line^M And another^M If you wish to remove the ^M, it can be that you delete each ^M by hand. Alter...

If you get an error like this: Fatal error: Call to a member function fetch_assoc() on boolean in C:\xampp\htdocs\stack\index.php on line 7 Other variations include something along the lines of: mysql_fetch_assoc() expects parameter 1 to be resource, boolean given... These errors mean that t...

You first need to run a Stanford CoreNLP server: java -mx4g -cp "*" edu.stanford.nlp.pipeline.StanfordCoreNLPServer -port 9000 -timeout 50000 Here is a code snippet showing how to pass data to the Stanford CoreNLP server, using the pycorenlp Python package. from pycorenlp import Stanf...

My first Wicket setup, app showing Hello World on home screen: import org.apache.wicket.protocol.http.WebApplication; public class HelloWorldApplication extends WebApplication { public HelloWorldApplication() { } @Override public Class getHomePage() { retur...

class MyDataObject extends DataObject { private static $singular_name = 'My Object'; private static $plural_name = 'My Objects'; ... }

class MyDataObject extends DataObject { private static $db = array( 'Name' => 'Varchar' ); private static $has_one = array( 'OtherDataObject' => 'OtherDataObject' ); private static $summary_fields = array( 'Name', 'OtherDat...

class MyDataObject extends DataObject { private static $db = array( 'Name' => 'Varchar' ); private static $has_one = array( 'OtherDataObject' => 'OtherDataObject' ); private static $summary_fields = array( 'Name', 'OtherDat...

class MyDataObject extends DataObject { ... private static $has_many = array( 'OtherDataObjects' => 'OtherDataObject' ); function getCMSFields() { $fields = parent::getCMSFields(); if ($gridField = $fields->dataFieldByName('OtherDataObject...

class MyAdmin extends ModelAdmin { ... function getEditForm($id = null, $fields = null) { $form = parent::getEditForm($id, $fields); if ($this->modelClass == 'MyDataObjectName') { $form->Fields() ->fieldByName($this->sanitis...

Objects that respond to to_proc can be converted to procs with the & operator (which will also allow them to be passed as blocks). The class Symbol defines #to_proc so it tries to call the corresponding method on the object it receives as parameter. p [ 'rabbit', 'grass' ].map( &:upcase ) ...

To check whether a value is a character use the is.character() function. To coerce a variable to a character use the as.character() function. x <- "The quick brown fox jumps over the lazy dog" class(x) [1] "character" is.character(x) [1] TRUE Note that numerics can be ...

str.contains() method can be used to check if a pattern occurs in each string of a Series. str.startswith() and str.endswith() methods can also be used as more specialized versions. In [1]: animals = pd.Series(['cat', 'dog', 'bear', 'cow', 'bird', 'owl', 'rabbit', 'snake']) Check if strings con...

In [1]: ser = pd.Series(['lORem ipSuM', 'Dolor sit amet', 'Consectetur Adipiscing Elit']) Convert all to uppercase: In [2]: ser.str.upper() Out[2]: 0 LOREM IPSUM 1 DOLOR SIT AMET 2 CONSECTETUR ADIPISCING ELIT dtype: object All lowercase: In [3]: ser...

You can think of an OperationQueue as a line of tasks waiting to be executed. Unlike dispatch queues in GCD, operation queues are not FIFO (first-in-first-out). Instead, they execute tasks as soon as they are ready to be executed, as long as there are enough system resources to allow for it. Get th...

The Foundation framework provides the Operation type, which represents a high-level object that encapsulates a portion of work that may be executed on a queue. Not only does the queue coordinate the performance of those operations, but you can also establish dependencies between operations, create c...