# File lib/powerbar.rb, line 394 def append(at, v) return if @sample_interval > at - @last_sample_at @sample_interval += @sample_interval_step_up if @sample_interval < @sample_interval_max rate = (v - @counter) / (at - @last_sample_at).to_f return if rate.nan? @last_sample_at = at @counter = v self << rate shift while @window < length self end