class Array
  def sum
    if block_given?
      inject(0) {|sum, x| sum + yield(x) }
    else
      inject(0) {|sum, x| sum + x }
    end
  end

  def mean(&block)
    sum(&block).to_f / size
  end

  def variance
    # E(x^2) - E(x)^2
    mean{|x| x ** 2 } - mean ** 2
  end

  def deviation
    Math.sqrt(variance)
  end
end

class Compare
  def initialize(command, range = 1..ARGV[0].to_i)
    if ARGV.empty? then puts "Dude, pass how many iterations you wanna run for"; break; end
    @name = command.match(/ (.+)\./)[0].chop.lstrip  # need to replace with a better regexp
    @array = range.collect { `#{command}`.scan(/\d+:/).last.chop.to_i }
  end

  def output
    puts "#{@name} - average number of iterations: #{@array.mean}  - standard deviation of iteration values: #{@array.deviation}"
    puts @array.join(', ')
  end
end

time = Time.now

Compare.new("ruby original.rb").output
#Compare.new("runhaskell original.hs").output

puts "#{Time.now - time} seconds"