convert a mixed number string to a decimal in Ruby

decimalize.rb

  def decimalize(string)
    return 0.0 if string.nil? || string.empty?
    string.gsub!(/[^\d\s\/]/, "")
    fraction, numeral = string.split.reverse
    fraction ||= '0/1'
    numeral.to_i + Rational(fraction).to_f
  end

# decimalize('1 1/2') => 1.5
# decimalize('2 3/4 inches') => 2.75
# decimalize('3 11/8') => 4.375
# decimalize('') => 0.0
# decimalize(nil) => 0.0