Nodejs Array Random random(num, enableDuplicate)

Method Source Code

Array.prototype.random = function(num, enableDuplicate){
   var array = [];
   var duplicate;
   if(typeof duplicate === "undefined"){
      duplicate = false;/*from w w  w  . ja v a  2  s  .c  o m*/
   }
   else{
      duplicate = enableDuplicate;
   }
   if(num <= this.length){
      var index;
      for(var i=0; i<num; i++){
         index = Math.floor(Math.random()*this.length);
         array.push(this[index]); 
         if(!enableDuplicate){
            this.splice(index, 1);
         }   
      }
      return array;
   }   
}
module.exports = Array;

Related

1. random()

   Array.prototype.random = function()
     return this[Random(0, this.length - 1)];
   

2. random()

   Array.prototype.random = function() {
     if (this.length == 0) return void 0;
     return this[Math.floor(Math.random() * this.length)];
   };
   

3. random(i)

   Array.prototype.random = function(i) {
       var random = [];
       for(; i > 0;) {
           random.push(this[Math.random() * this.length | 0]);
           i--;
       return random;
   };
   var usedNames = {};
   ...
   

4. random(last)

   Array.prototype.random = function(last) {
       var num = 0;
       do {
          num = Math.floor(Math.random() * this.length);
       } while (this[num] == last);
       return this[num];
   

5. random(nelm)

   Array.prototype.random = function(nelm) {
     nelm = nelm || 1;
     if (nelm <= 0) {
       nelm = 1;
     if (nelm === 1) {
       return this[Math.floor(Math.random() * this.length)];
     var ret = [], i;
   ...
   

6. randomElement()

   Array.prototype.randomElement = function () {
       return this[Math.floor(Math.random() * this.length)]
   

7. randomElement()

   function Weather() {
     this.currentWeather = ['stormy', 'sunny', 'sunny', 'sunny'].randomElement();
   Array.prototype.randomElement = function () {
     return this[Math.floor(Math.random() * this.length)];
   };
   

8. randomElement()

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

9. randomPick()

   Array.prototype.randomPick = function () {
       return this[_.random(this.length - 1)];
   };