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Specific to Windows System and android Phone: Requirements: USB Cable Android Device Android Driver Software Basically after connecting USB cable PC detects the Android Device and it will automatically search for the required Drivers for that Android Device. If that drivers are not found th...

Removing duplicate values in a list can be done by converting the list to a set (that is an unordered collection of distinct objects). If a list data structure is needed, then the set can be converted back to a list using the function list(): names = ["aixk", "duke", "edik&...

It is possible, inside a closure, to use an external variable with the special keyword use. For instance: <?php $quantity = 1; $calculator = function($number) use($quantity) { return $number + $quantity; }; var_dump($calculator(2)); // Shows "3" You can go further by ...

In general, an observer is a class with a specific method being called when an action on the observed object occurs. In certain situations, closures can be enough to implement the observer design pattern. Here is a detailed example of such an implementation. Let's first declare a class whose purpos...

We define two sets a and b >>> a = {1, 2, 2, 3, 4} >>> b = {3, 3, 4, 4, 5} NOTE: {1} creates a set of one element, but {} creates an empty dict. The correct way to create an empty set is set(). Intersection a.intersection(b) returns a new set with elements present in bot...

Even though Python natively supports big integers, taking the nth root of very large numbers can fail in Python. x = 2 ** 100 cube = x ** 3 root = cube ** (1.0 / 3) OverflowError: long int too large to convert to float When dealing with such large integers, you will need to use a custom f...

git is fundamentally a key-value store. When you add data to git, it builds an object and uses the SHA-1 hash of the object's contents as a key. Therefore, any content in git can be looked up by it's hash: git cat-file -p 4bb6f98 There are 4 types of Object: blob tree commit tag

A commit is probably the object type most familiar to git users, as it's what they are used to creating with the git commit commands. However, the commit does not directly contain any changed files or data. Rather, it contains mostly metadata and pointers to other objects which contain the actual c...

A tree basically represents a folder in a traditional filesystem: nested containers for files or other folders. A tree contains: 0 or more blob objects 0 or more tree objects Just as you can use ls or dir to list the contents of a folder, you can list the contents of a tree object. $ git ca...

A blob contains arbitrary binary file contents. Commonly, it will be raw text such as source code or a blog article. But it could just as easily be the bytes of a PNG file or anything else. If you have the hash of a blob, you can look at it's contents. $ git cat-file -p d429810 package com.exampl...

The git commit command does a few things: Create blobs and trees to represent your project directory - stored in .git/objects Creates a new commit object with your author information, commit message, and the root tree from step 1 - also stored in .git/objects Updates the HEAD ref in .git/HEAD t...

Running git checkout -b <refname> will create a new ref that points to the current commit. $ cat .git/head 1f324a $ git checkout -b TestBranch $ cat .git/refs/heads/TestBranch 1f324a

The non-block do construct looks like integer i do 100, i=1, 5 100 print *, i That is, where the labelled termination statement is not a continue statement. There are various restrictions on the statement that can be used as the termination statement and the whole thing is generally v...

MySQL's DELETE statement can use the JOIN construct, allowing also to specify which tables to delete from. This is useful to avoid nested queries. Given the schema: create table people ( id int primary key, name varchar(100) not null, gender char(1) not null ); insert people (id,na...

The reduce function can be used to sum the elements in a list. (reduce '+ '(1 2 3 4)) ;;=> 10 By default, reduce performs a left-associative reduction, meaning that the sum 10 is computed as (+ (+ (+ 1 2) 3) 4) The first two elements are summed first, and then that result (3) is added to...

Common Lisp already has a reverse function, but if it didn't, then it could be implemented easily using reduce. Given a list like (1 2 3) === (cons 1 (cons 2 (cons 3 '()))) the reversed list is (cons 3 (cons 2 (cons 1 '()))) === (3 2 1) That may not be an obvious use of reduce, but if we ha...

You can use curl: curl -o- https://raw.githubusercontent.com/creationix/nvm/v0.31.3/install.sh | bash Or you can use wget: wget -qO- https://raw.githubusercontent.com/creationix/nvm/v0.31.3/install.sh | bash

Listing available remote versions for installation nvm ls-remote Installing a remote version nvm install <version> For example nvm install 0.10.13

To list available local versions of node through NVM: nvm ls For example, if nvm ls returns: $ nvm ls v4.3.0 v5.5.0 You can switch to v5.5.0 with: nvm use v5.5.0

The prop-types package allows you to add runtime type checking to your component that ensures the types of the props passed to the component are correct. For instance, if you don't pass a name or isYummy prop to the component below it will throw an error in development mode. In production mode the p...