Is there a JavaScript function that reduces a fraction

Question

say we have fraction 2/4, it can be reduced to 1/2.

Is there a JavaScript function that can do the reducing?

Answer 1

// Reduce a fraction by finding the Greatest Common Divisor and dividing by it. function reduce(numerator,denominator){   var gcd = function gcd(a,b){     return b ? gcd(b, a%b) : a;   };   gcd = gcd(numerator,denominator);   return [numerator/gcd, denominator/gcd]; }  reduce(2,4); // [1,2]  reduce(13427,3413358); // [463,117702] 

Answer 2

No, but you can write one yourself fairly easily. Essentially you need to divide the top and bottom parts of the fraction by their 'Greatest Common Denominator'... Which you can calculate from Euclid's algorithm.

Read here for more info: http://www.jimloy.com/number/euclids.htm

edit:

code (because everyone seems to be doing it, this doesn't use recursion though)

var FractionReduce = (function(){     //Euclid's Algorithm     var getGCD = function(n, d){         var numerator = (n<d)?n:d;         var denominator = (n<d)?d:n;                 var remainder = numerator;         var lastRemainder = numerator;          while (true){             lastRemainder = remainder;             remainder = denominator % numerator;             if (remainder === 0){                 break;             }             denominator = numerator;             numerator = remainder;         }         if(lastRemainder){             return lastRemainder;         }     };      var reduce = function(n, d){         var gcd = getGCD(n, d);          return [n/gcd, d/gcd];     };      return {             getGCD:getGCD,             reduce:reduce            };  }());  alert(FractionReduce.reduce(3413358, 13427));