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Two erlang processes can communicate with each other, wich is also known as message passing. This procedure is asynchronous in the form that the sending process will not halt after sending the message. Sending Messages This can be achieved with the construct Pid ! Message, where Pid is a valid pr...

using System.Text.RegularExpressions; string pattern = ":(.*?):"; string lookup = "--:text in here:--"; // Instanciate your regex object and pass a pattern to it Regex rgxLookup = new Regex(pattern, RegexOptions.Singleline, TimeSpan.FromSeconds(1)); // Get the match from y...

using System.Text.RegularExpressions; List<string> found = new List<string>(); string pattern = ":(.*?):"; string lookup = "--:text in here:--:another one:-:third one:---!123:fourth:"; // Instanciate your regex object and pass a pattern to it Regex rgxLookup = ...

class Product(models.Model): name = models.CharField(max_length=20) price = models.FloatField() To Get average price of all products: >>> from django.db.models import Avg, Max, Min, Sum >>> Product.objects.all().aggregate(Avg('price')) # {'price__avg': 124.0} To ...

PL/SQL stands for Procedural Language extensions to SQL. PL/SQL is available only as an "enabling technology" within other software products; it does not exist as a standalone language. You can use PL/SQL in the Oracle relational database, in the Oracle Server, and in client-side applicati...

Subtracting the values of two pointers to an object results in a signed integer *1. So it would be printed using at least the d conversion specifier. To make sure there is a type being wide enough to hold such a "pointer-difference", since C99 <stddef.h> defines the type ptrdiff_t. ...

Most performance tips are very dependent of the current state of JS engines and are expected to be only relevant at a given time. The fundamental law of performance optimization is that you must first measure before trying to optimize, and measure again after a presumed optimization. To measure cod...

The package's official wiki has some essential materials: As a new user, you will want to check out the vignettes, FAQ and cheat sheet. Before asking a question -- here on StackOverflow or anywhere else -- please read the support page. For help on individual functions, the syntax is h...

Go to application/model File name - Home_model.php Inside the file class Home_model extends CI_Model { public $variable; public function __construct() { parent::__construct(); } public function get_data() { $query = $this->db->get('tabl...

Syntax - $this->load->model('model_name'); Practice - $this->load->model('home_model'); If you would like your model assigned to a different object name you can specify it via the second parameter of the loading method: Syntax - $this->load->model('model_name', 'foobar'); ...

Syntax $this->load->model('model_name'); $this->model_name->method_name(); Practice $this->load->model('home_model'); $this->home_model->get_data();

Syntax $array = array( '' => , ); # can pass array $singelData = ''; # something just a filed value $this->load->model('model_name'); $this->model_name->method_name($singelData, $array); Practice $array = array( 'name' => 'codeigniter', 'version' =&g...

public function method_name($single, $array) { echo $single; print_r($array); } Beware with the order which pass from controller to model.

Python makes it extremely intuitive to check if a string contains a given substring. Just use the in operator: >>> "foo" in "foo.baz.bar" True Note: testing an empty string will always result in True: >>> "" in "test" True

Javascript engines first look for variables within the local scope before extending their search to larger scopes. If the variable is an indexed value in an array, or an attribute in an associative array, it will first look for the parent array before it finds the contents. This has implications wh...

Open index.ios.js or index.android.js and delete everything between the <View> </View>. After that, write <Text> Hello World! </Text> and run the emulator. You should see Hello World! written on the screen! Congrats! You've successfully written your first Hello World!

ACID tables are supported since hive 0.14 version. Below table supports UPDATE/DELETE/INSERT Below configuration changes required in hive-site.xml. hive.support.concurrency = true hive.enforce.bucketing = true hive.exec.dynamic.partition.mode = nonstrict hive.txn.manager =org.apache.hadoop...

You can evaluate any valid C# code: int value = await CSharpScript.EvaluateAsync<int>("15 * 89 + 95"); var span = await CSharpScript.EvaluateAsync<TimeSpan>("new DateTime(2016,1,1) - DateTime.Now"); If type is not specified, the result is object: object value = ...

{-# LANGUAGE RecordWildCards #-} data Client = Client { firstName :: String , lastName :: String , clientID :: String } deriving (Show) printClientName :: Client -> IO () printClientName Client{..} = do p...

# example data DT = as.data.table(mtcars, keep.rownames = TRUE) Editing a column Use the := operator inside j to create new columns or modify existing ones: DT[, mpg_sq := mpg^2] Editing on a subset of rows Use the i argument to subset to rows "where" edits should be made: DT[1:...