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The coordinate systems of Matplotlib come very handy when trying to annotate the plots you make. Sometimes you would like to position text relatively to your data, like when trying to label a specific point. Other times you would maybe like to add a text on top of the figure. This can easily be achi...

SELECT DATE('2003-12-31 01:02:03'); The output will be: 2003-12-31

Use git revert to revert existing commits, especially when those commits have been pushed to a remote repository. It records some new commits to reverse the effect of some earlier commits, which you can push safely without rewriting history. Don't use git push --force unless you wish to bring down ...

Visitor pattern allows you to add new operations or methods to a set of classes without modifying the structure of those classes. This pattern is especially useful when you want to centralise a particular operation on an object without extending the object Or without modifying the object. UML diag...

Consider using Extension Methods as Functions which wrap other code, here's a great example that uses both a static method and and extension method to wrap the Try Catch construct. Make your code Bullet Proof... using System; using System.Diagnostics; namespace Samples { /// <summary&g...

Database connections are set up using the CF Administrator tool. See Database Connections for how to connect a datasource. To execute queries all you need is the <cfquery> tag. The <cfquery> tag connects to and opens the database for you, all you need to do is supply it with the name of...

namespace HelloWorld; interface type App = class public class method Main(args: array of String); end; implementation class method App.Main(args: array of String); begin Console.WriteLine('Hello World'); end; end.

Lambda expressions are similar to anonymous functions in other languages. Lambda expressions are open formulas which also specify variables which are to be bound. Evaluation (finding the value of a function call) is then achieved by substituting the bound variables in the lambda expression's body, ...

It is sometimes required for a process to concurrently write and read the same "data". The ReadWriteLock interface, and its ReentrantReadWriteLock implementation allows for an access pattern that can be described as follow : There can be any number of concurrent readers of the data. If...

using System; using System.Runtime.InteropServices; namespace ComLibrary { [ComVisible(true)] public interface IMainType { int GetInt(); void StartTime(); int StopTime(); } [ComVisible(true)] [ClassInterface(ClassInterfaceType.N...

Extensions add new functionality to an existing class, structure, enumeration, or protocol type. This includes the ability to extend types for which you do not have access to the original source code. Extensions in Swift can: Add computed properties and computed type properties Define instance ...

In the Xcode, you have three separate areas of working - Navigators (in red), Debug area(in green) and Utilities(in blue). The workspace window always includes the editor area. When you select a file in your project, its contents appear in the editor area, where Xcode opens the file in an appropri...

You can specify your Lint checking preferences in the lint.xml file. If you are creating this file manually, place it in the root directory of your Android project. If you are configuring Lint preferences in Android Studio, the lint.xml file is automatically created and added to your Android project...

You can disable Lint checking from your Java and XML source files. Configuring lint checking in Java To disable Lint checking specifically for a Java class or method in your Android project, add the @SuppressLint annotation to that Java code. Example: @SuppressLint("NewApi") @Override...

Now that you have an object, it might be good to figure out what it is. You can use the Get-Member cmdlet to see what an object is and what it contains: Get-Item c:\windows | Get-Member This yields: TypeName: System.IO.DirectoryInfo Followed by a list of properties and methods the object ha...

The [RegularExpression] attribute can decorate any properties or public fields and specifies a regular expression that must be matched for the property be considered valid. [RegularExpression(validationExpression)] public string Property { get; set; } Additionally, it accepts an optional ErrorM...

Meteor reads a mobile-config.js file in the root of your app directory during build, and uses the settings specified there to generate Cordova’s config.xml. Project_folder ├── /.meteor └── mobile-config.js Most configurations can be achieved with mobile-config.js (app metadata, preferences, ...

The clearfix hack is a popular way to contain floats (N. Gallagher aka @necolas) Not to be confused with the clear property, clearfix is a concept (that is also related to floats, thus the possible confusion). To contain floats, you've to add .cf or .clearfix class on the container (the parent)...

Sometimes you may want to perform some additional actions to Auto Layout calculations done by UIKit itself. Example: when you have a UIView that has a maskLayer, you may need to update maskLayer as soon as Auto Layout changes UIView's frame // CustomView.m - (void)layoutSubviews { [super la...

Using the same example as Evaluating a NodeList in an XML document, here is how you would make multiple XPath calls efficiently: Given the following XML document: <documentation> <tags> <tag name="Java"> <topic name="Regular expression...