class BenchmarkDriver::Output::Compare

def pretty_sec(sec, iter)
  r = Rational(sec, iter)
  case
  when r >= 1
    "#{'%3.2f' % r.to_f}s"
  when r >= 1/1000r
    "#{'%3.2f' % (r * 1_000).to_f}ms"
  when r >= 1/1000_000r
    "#{'%3.2f' % (r * 1_000_000).to_f}μs"
  else
    "#{'%3.2f' % (r * 1_000_000_000).to_f}ns"
  end
end