Tutorial by Topics: le

Data.table is a package that extends the functionality of data frames from base R, particularly improving on their performance and syntax. See the package's Docs area at Getting started with data.table for details. DT[i, j, by] # DT[where, select|update|do, by] DT[...][...] # chaining ####...

Debug.Print(string) Stop() / Stop

A CSS distance measurement is a number immediately followed by a length unit (px, em, pc, in, …) CSS supports a number of length measurements units. They are absolute or relative. valueunit 1em UnitDescription%Define sizes in terms of parent objects or current object dependent on prope...

A Virtual Environment is a tool to keep the dependencies required by different projects in separate places, by creating virtual Python environments for them. It solves the “Project X depends on version 1.x but, Project Y needs 4.x” dilemma, and keeps your global site-packages directory clean and man...

A UIAlertController object displays an alert message to the user. This class replaces the UIActionSheet and UIAlertView classes for displaying alerts. After configuring the alert controller with the actions and style you want, present it using the presentViewController:animated:completion: ...

This section provides an overview of what selenium-webdriver is, and why a developer might want to use it. It should also mention any large subjects within selenium-webdriver, and link out to the related topics. Since the Documentation for selenium-webdriver is new, you may need to create initia...

Lens is a library for Haskell that provides lenses, isomorphisms, folds, traversals, getters and setters, which exposes a uniform interface for querying and manipulating arbitrary structures, not unlike Java's accessor and mutator concepts. What is a Lens? Lenses (and other optics) allow us...

Gradle is an open-source, general-purpose build tool. It is popular in the Java community and is the preferred build tool for Android. Highlighted Gradle features Declarative build scripts are code written in Groovy or Kotlin. Lots of core and community plugins which use a flexible, convent...

Pseudo-elements, just like pseudo-classes, are added to a CSS selectors but instead of describing a special state, they allow you to scope and style certain parts of an html element. For example, the ::first-letter pseudo-element targets only the first letter of a block element specified by the sel...

A tuple is a immutable list of values. Tuples are one of Python's simplest and most common collection types, and can be created with the comma operator (value = 1, 2, 3). (1, a, "hello") # a must be a variable () # an empty tuple (1,) # a 1-element tuple. (1) is not a tu...

There are two ways to get the GAE SDK (the standalone GAE SDK vs Google Cloud SDK gcloud). There are slight differences when the deploying the app using gcloud. If you are using gcloud, you can use gcloud app deploy ~/my_app/app.yaml. The behaviour is different from using the old appcfg.py. If you...

An .htaccess file controls how Apache interacts with your site. When an .htaccess file is placed in your domain’s directory (usually root directory), the file is detected and executed by Apache. An .htaccess file is commonly used for the following: Denying specific IPs to your site Password p...

file, err := os.Open(name) // Opens a file in read-only mode. A non-nil error is returned if the file could not be opened. file, err := os.Create(name) // Creates or opens a file if it already exists in write-only mode. The file is overwritten to if it already exists. A non-nil error is returned...

scikit-learn is a general-purpose open-source library for data analysis written in python. It is based on other python libraries: NumPy, SciPy, and matplotlib scikit-learncontains a number of implementation for different popular algorithms of machine learning.