Nodejs Array Mean mean()

Method Source Code

Array.prototype.mean = function() {
    return !this.length ? 0
        : this.reduce(function(pre, cur, i) {
            return (pre * i + cur) / (i + 1);
            });/*from   w w w .  j  a  v  a2 s .  c o  m*/
    }

console.log( [1,2,3,4,5].mean() );   // 3
console.log( [].mean() );            // 0

Related

1. mean()

   Array.prototype.mean = function () {
     var sum = this.reduce(
       function (prev, cur) {
         return prev + cur;
     );
     return sum / this.length;
   

2. mean()

   Array.prototype.mean = function(){ 
     return this.reduce(function(previousMean, currentValue, i){
       return previousMean + (1/(i + 1))*(currentValue - previousMean);
     });
   };
   Array.prototype.median = function() {
      var values = this;
       values.sort( function(a,b) {return a - b;} );
       var half = Math.floor(values.length/2);
   ...
   

3. mean()

   Array.prototype.mean = function () {
       var sum = this.reduce(function(previousValue, currentValue) {
           return previousValue + currentValue;
       });
       return sum / this.length;
   };
   

4. mean()

   Array.prototype.mean = function() {
       mean = 0;
       for (var i = 0; i < this.length; i++) {
           mean += this[i];
       mean = mean / this.length;
       return mean;
   };