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Bridge pattern decouples abstraction from implementation so that both can vary independently. It has been achieved with composition rather than inheritance. Bridge UML diagram from wikipedia: You have four components in this pattern. Abstraction: It defines an interface RefinedAbstraction: It ...
example: df = pd.DataFrame({'group1' : ['A', 'A', 'A', 'A', 'B', 'B', 'B', 'B'], 'group2' : ['C', 'C', 'C', 'D', 'E', 'E', 'F', 'F'], 'B' : ['one', np.NaN, np.NaN, np.NaN, ...
If the value of the href-attribute begins with tel:, your device will dial the number when you click it. This works on mobile devices or on computers/tablets running software – like Skype or FaceTime – that can make phone calls. <a href="tel:11234567890">Call us</a> Most de...
SUB function allows to substitute text inside awk sub(regexp, replacement, target) where regexp could be a full regular expression $ cat file AAAAA BBBB CCCC DDDD EEEE FFFF GGGG $ awk '{sub("AAA","XXX", $0); print}' file XXXAA BBBB CCCC DDDD EEEE FFFF GGGG ...
A Range cannot be created or populated the same way a string would: Sub RangeTest() Dim s As String Dim r As Range 'Specific Type of Object, with members like Address, WrapText, AutoFill, etc. ' This is how we fill a String: s = "Hello World!" ' But we can...
# example data DT = data.table(iris) DT[, Bin := cut(Sepal.Length, c(4,6,8))] To apply the same summarizing function to every column by group, we can use lapply and .SD DT[, lapply(.SD, median), by=.(Species, Bin)] # Species Bin Sepal.Length Sepal.Width Petal.Length Petal.Width # 1...
To declare a bean, simply annotate a method with the @Bean annotation or annotate a class with the @Component annotation (annotations @Service, @Repository, @Controller could be used as well). When JavaConfig encounters such a method, it will execute that method and register the return value as a b...
Setup Ruby On Rails on Ubuntu 16.04 Xenial Xerus All commands should be run in Linux terminal (hotkey: Ctrl + Alt + T) You need to install Ruby on your local machine in development environment. The first step is to install some dependencies for Ruby. sudo apt-get update sudo apt-get install git...
Enabled directory index means that if someone access to any folder which don't contains index.php , index.html, index.htm or any other default file defined in DirectoryIndex in apache configuration then all files in that folder will be listed in browser if you try to visit that page. Often director...
Problem There is a series of repeating elements in page that you need to know which one an event occurred on to do something with that specific instance. Solution Give all common elements a common class Apply event listener to a class. this inside event handler is the matching selector elemen...
Be aware that Microsoft Excel 2013 (and higher) uses Single Document Interface (SDI) and that Excel 2010 (And below) uses Multiple Document Interfaces (MDI). This implies that for Excel 2013 (SDI), each workbook in a single instance of Excel contains its own ribbon UI: Conversely for Excel...
A function is a block of code that will be called several times during the execution. Instead of writing the same piece of code again and again, one can write this code inside a function and call that function whenever it is needed. A function : Must be declared in a class or a module Returns a...
Configuring your environment RabbitMQ looks for an set of environment variables in /etc/rabbitmq/rabbitmq-env.conf. If it does not exist, it assumes default values. All values in rabbitmq-env.conf get exported to the environment the RabbitMQ server runs in with a RABBITMQ_ prefix; this prefix is no...
From the documentation : In C#, arguments can be passed to parameters either by value or by reference. Passing by reference enables function members, methods, properties, indexers, operators, and constructors to change the value of the parameters and have that change persist in the calling e...
Detailed instructions on getting silverlight set up or installed.
The DATE data type does not handle time zones or changes in daylight savings time. Either: use the TIMESTAMP WITH TIME ZONE data type; or handle the changes in your application logic. A DATE can be stored as Coordinated Universal Time (UTC) and converted to the current session time zone like...
There is overflow in the following code int x = int.MaxValue; Console.WriteLine(x + x + 1L); //prints -1 Whereas in the following code there is no overflow int x = int.MaxValue; Console.WriteLine(x + 1L + x); //prints 4294967295 This is due to the left-to-right ordering of the operations...
Command line arguments parsing is Go is very similar to other languages. In you code you just access slice of arguments where first argument will be the name of program itself. Quick example: package main import ( "fmt" "os" ) func main() { progName := o...
Using the document-ready event can have small performance drawbacks, with delayed execution of up to ~300ms. Sometimes the same behavior can be achieved by execution of code just before the closing </body> tag: <body> <span id="greeting"></span> world! <sc...
You can create a task (Console Command) in Laravel using Artisan. From your command line: php artisan make:console MyTaskName This creates the file in app/Console/Commands/MyTaskName.php. It will look like this: <?php namespace App\Console\Commands; use Illuminate\Console\Command; c...

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