Here you can find the source of average()
Array.prototype.average = function () { var sum = 0, j = 0; for (var i = 0; i < this.length, isFinite(this[i]); i++) { sum += parseFloat(this[i]); ++j; }/*from w w w .jav a2s. c om*/ return j ? sum / j : 0; };
Array.prototype.average = function () { return this.sum() / this.length
Array.prototype.average = function(){ return this.reduce( (a,b) => a + b, 0) / this.length
Array.prototype.average = function () { return this.sum() / this.length; }; console.log([1, 2, 3, 4].average());
Array.prototype.average = function () { return (!this.length) ? NaN : this.reduce((acc, value) => { return acc + value; }) / this.length; };
Array.prototype.average = function() if (this.length < 1) { return Number.NaN; return this.sum() / this.length;
Array.prototype.average = function() { var sum = this.sum(); var count = this.length; return sum/count;
Array.prototype.average = function(){ var sum = 0; for (var i of this){ sum += i; return sum / this.length;
Array.prototype.average = function(arr) { if(!arr) arr = this; var len = arr.length, i, avg = 0; for( i = 0; i < len; i++ ) { avg += arr[i]; return avg / len;
Array.prototype.average = function (fun) { return this.sum(fun) / this.length; };