Ruby function to detect the factors of a Fixednum.

factorize.rb

# @author David Wortham <djwortham+programming@gmail.com>
# @date 2011-04-30
# @license MIT License: http://www.opensource.org/licenses/mit-license.php

def factorize(input)
  remainingInput  = input
  factors = {}
  i       = 2
  while i <= remainingInput
    while remainingInput % i == 0
      if factors[i] == nil
        factors[i] = 1
      else
        factors[i] = factors[i] + 1
      end
      remainingInput = remainingInput / i
    end
    i = i + 1
  end
  return factors
end

# usage:
# allFactors = factors(12345)

# tip: reassemble factors:
# product = 1
# allFactors.each{|factor, times| product = product * (factor ** times)}