def frequency

      return brute_frequency unless @seconds && @seconds.length > 1

      delta = 60
      prev = @seconds[0]

      @seconds[1..-1].each do |sec|
        d = sec - prev
        delta = d if d < delta
      end

      delta
    end
def frequency

      return brute_frequency unless @seconds && @seconds.length > 1

      delta = 60
      prev = @seconds[0]

      @seconds[1..-1].each do |sec|
        d = sec - prev
        delta = d if d < delta
      end

      delta
    end
Returns a quickly computed approximation of the frequency for this
 cron line.

 #brute_frequency, on the other hand, will compute the frequency by
 examining a whole, that can take more than seconds for a seconds
 level cron...