A prototype for Number.toFixed in JavaScript

if toFixed is not defined

1. if (!num.toFixed)
2. {
4.  Number.prototype.toFixed = function(precision) {
5.      var power = Math.pow(10, precision || 0);
6.      return String(Math.round(this * power)/power);
7.  }
9. }
11. // OR
13.   Number.prototype.toFixed = function(precision)
14.   {
15.      var num = (Math.round(this*Math.pow(10,precision))).toString();
16.      return num.substring(0,num.length-precision) + “.” +
17.             num.substring(num.length-precision, num.length);
18.   }