Nodejs Array Shuffle shuffle()

Method Source Code

// Randomizes the element ordering and returns the Array

Array.prototype.shuffle = function() {

    // Prototypes throw TypeErrors when the context or arguments are invalid

    if (Object.prototype.toString.call(this) !== '[object Array]') {
        throw new TypeError("`this` must be Array, not " + typeof this);
    }//from   w w  w .  j  a va  2 s. c o  m
    
    var length = this.length;
    
    // Fisher?Yates implementation ("gold standard" of shuffles)

    for (var i = length - 1; i >= 0; i--) {
        var randomIndex = Math.floor(Math.random() * length),
            temp = this[i];

        this[i] = this[randomIndex];
        this[randomIndex] = temp;
    }

    return this;
};

Related

1. shuffle()

   const ranks = [1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 11, 12, 13],
   suits = ["heart", "club", "diamond", "spade"];
   function Card(rank, suit) {
     this.rank = rank;
     this.suit = suit;
   function newDeck() {
     const deck = [];
     for(let i = 1; i < 14; i++){
   ...
   

2. shuffle()

   Array.prototype.shuffle = function () { 
     for(var j, x, i = this.length; i; j = Math.floor(Math.random() * i), x = this[--i], this[i] = this[j], this[j] = x);
     return this;
   };
   console.log("#FFFEFA".split(", ").shuffle());
   

3. shuffle()

   Array.prototype.shuffle = function () {
     for(var j, x, i = this.length; i; j = Math.floor(Math.random() * i), x = this[--i], this[i] = this[j], this[j] = x);
     return this;
   };
   

4. shuffle()

   Array.prototype.shuffle = function(){
      var new_arr = this.slice(0);
    for (var j, x, i = new_arr.length; i; j = Math.floor(Math.random() * i), x = new_arr[--i], new_arr[i] = new_arr[j], new_arr[j] = x);
      return new_arr;
   

5. shuffle()

   Array.prototype.shuffle = function() {
     var currentIndex = this.length, temporaryValue, randomIndex;
     while (0 !== currentIndex) {
       randomIndex = Math.floor(Math.random() * currentIndex);
       currentIndex -= 1;
       temporaryValue = this[currentIndex];
       this[currentIndex] = this[randomIndex];
       this[randomIndex] = temporaryValue;
   

6. shuffle()

   Array.prototype.shuffle = function(){
     var length = this.length;
     var i, j, temp;
     for(i = length - 1; i >= 0; i--){
       j = Math.floor(Math.random()*(i+1));
       temp = this[i];
       this[i] = this[j];
       this[j] = temp;
     return this;
   };
   var testArray = [1,2,3,4,5,6,7,8,9,10];
   console.log(testArray.shuffle());
   console.log(testArray);
   

7. shuffle()

   Array.prototype.shuffle = function(){
     var result = [];
     while(this.length > 0 ){
       result.push( this.splice(Math.floor(Math.random() * this.length), 1)[0] );
     return result;
   };
   

8. shuffle()

   Array.prototype.shuffle = function(){
     for (var i = 0; i < this.length; i++){
         var a = this[i];
         var b = Math.floor(Math.random() * this.length);
         this[i] = this[b];
         this[b] = a;
   function shuffleProperties(obj) {
   ...
   

9. shuffle()

   Array.prototype.shuffle = function () {
       let array = this, arraylength = array.length, randomIndex, temp;
       while (arraylength) {
           randomIndex = Math.floor(Math.random(arraylength) * arraylength--);
           temp = array[arraylength];
           array[arraylength] = array[randomIndex];
           array[randomIndex] = temp;
       return array;
   ...