Tutorial by Examples: l

Sometimes you will have a grid of subplots, and you want to have a single legend that describes all the lines for each of the subplots as in the following image. In order to do this, you will need to create a global legend for the figure instead of creating a legend at the axes level (which wil...

Deferred function calls serve a similar purpose to things like finally blocks in languages like Java: they ensure that some function will be executed when the outer function returns, regardless of if an error occurred or which return statement was hit in cases with multiple returns. This is useful f...

pacman is a simple package manager for R. pacman allows a user to compactly load all desired packages, installing any which are missing (and their dependencies), with a single command, p_load. pacman does not require the user to type quotation marks around a package name. Basic usage is as follows:...

Not always we have liberty to read from or write to a local system path. For example if R code streaming map-reduce must need to read and write to file connection. There can be other scenarios as well where one is going beyond local system and with advent of cloud and big data, this is becoming incr...

C++11 It's possible to write a generic function (for example min) which accepts various numerical types and arbitrary argument count by template meta-programming. This function declares a min for two arguments and recursively for more. template <typename T1, typename T2> auto min(const T1 &...

Make project (compile modifed and dependent) Windows: Ctrl + F9 OS X / macOS: Cmd + F9 Compile selected file, package or module This is useful to know, as when debugging this shortcut can be used to quickly reload / hotswap classes. Windows: Ctrl + Shift + F9 OS X / macOS: Cmd + Shift + F9 Se...

Basic code completion (the name of any class, method or variable) Windows: Ctrl + Space OS X / macOS: Cmd + Space Smart code completion (filters the list of methods and variables by expected type) Windows: Ctrl + Shift + Space OS X / macOS: Cmd + Shift + Space Overwriting code with a suggestio...

Search everywhere Double Shift Find Windows / Linux: Ctrl + F OS X / macOS: Cmd + F Find next F3 Find previous Shift + F3 Replace Windows / Linux: Ctrl + R OS X / macOS: Cmd + R Find in path Windows / Linux: Ctrl + Shift + F OS X / macOS: Cmd + Shift + F Replace in path Windows / Lin...

module SomeMixin def foo puts "foo!" end end class Bar include SomeMixin def baz puts "baz!" end end b = Bar.new b.baz # => "baz!" b.foo # => "foo!" # works thanks to the mixin Now Bar is a mix of it...

PowerShell remoting must first be enabled on the server to which you wish to remotely connect. Enable-PSRemoting -Force This command does the following: Runs the Set-WSManQuickConfig cmdlet, which performs the following tasks: Starts the WinRM service. Sets the startup type on the WinRM ser...

Using credentials from your local computer: Enter-PSSession 192.168.1.1 Prompting for credentials on the remote computer Enter-PSSession 192.168.1.1 -Credential $(Get-Credential)

You can read an a binary file using this piece of code in all recent versions of Java: Java SE 1.4 File file = new File("path_to_the_file"); byte[] data = new byte[(int) file.length()]; DataInputStream stream = new DataInputStream(new FileInputStream(file)); stream.readFully(data); s...

static void Main(string[] args) { string url = "www.stackoverflow.com"; var pingTask = PingUrlAsync(url); Console.WriteLine($"Waiting for response from {url}"); Task.WaitAll(pingTask); Console.WriteLine(pingTask.Re...

Code in an else block will only be run if no exceptions were raised by the code in the try block. This is useful if you have some code you don’t want to run if an exception is thrown, but you don’t want exceptions thrown by that code to be caught. For example: try: data = {1: 'one', 2: 'two'}...

A basic AppComponent that depends on a single AppModule to provide application-wide singleton objects. @Singleton @Component(modules = AppModule.class) public interface AppComponent { void inject(App app); Context provideContext(); Gson provideGson(); } A module to use to...

2.3 The CoordinatorLayout is a container somewhat similar to FrameLayout but with extra capabilities, it is called super-powered FrameLayout in the official documentation. By attaching a CoordinatorLayout.Behavior to a direct child of CoordinatorLayout, you’ll be able to intercept touch events, wi...

java.util.Date to java.sql.Date conversion is usually necessary when a Date object needs to be written in a database. java.sql.Date is a wrapper around millisecond value and is used by JDBC to identify an SQL DATE type In the below example, we use the java.util.Date() constructor, that creates a D...

This code compiles: Integer arg = null; int x = arg; But it will crash at runtime with a java.lang.NullPointerException on the second line. The problem is that a primitive int cannot have a null value. This is a minimalistic example, but in practice it often manifests in more sophisticated f...

Sometimes a RecyclerView will need to use several types of Views to be displayed in the list shown in the UI, and each View needs a different layout xml to be inflated. For this issue, you may use different ViewHolders in single Adapter, by using a special method in RecyclerView - getItemViewType(i...

At run time the following would display a list of url in your console and continue computation payload = [{url:..., title:...}, {url=..., title=...}] main = payload |> List.map .url -- only takes the url |> Debug.log " My list of URLs" -- pass the url...