Shuffle Array - JavaScript ES2015, ES6

shuffle.js

// original gist
const shuffleArray = arr => arr.sort(() => Math.random() - 0.5);

// fully random by @BetonMAN
const shuffleArray = arr => arr
  .map(a => [Math.random(), a])
  .sort((a, b) => a[0] - b[0])
  .map(a => a[1]);

shuffleArray([1, 2, 3]) //[3, 1, 2]

Thanks. Very useful snippet, but it's missing a final close parenthesis.

In ES6 you can omit the closing parenthesis :)

But still its missing one ;)

ty guys!

What about objects?

Problem of this shuffle implementation is that it's not fully random. If you want really fully random shuffle, you need to use a code like this:

var array = [1,2,3,4,5,6,7,8,9];

var shuffled = array.map((a) => [Math.random(),a]).sort((a,b) => a[0]-b[0]).map((a) => a[1]);

For more information see this

@stamster wut?

@BetonMAN, neat implementation! It seems that the only downside, comparing to the implementation from Wikipedia, is that "the time and space complexity of the sort cannot be guaranteed as it is implementation dependent." MDN Array.sort . It is O(n) in the implementation of Fisher–Yates shuffle on Wikipedia .

Remember that the time complexity of sorting an array with length n is theta(n*log(n)), but the common shuffle algorithm takes theta(n). If the array is long, try to avoid sorting.