graphite-project/graphite-web — pull request #984 by andrewbaxter (2014-10-06 07:10:00+00:00)
Title: Delay function

This delays a series by a number of time steps. The delay method is the same as in derivative (Nones appended to the beginning).

Our immediate use case is computing a derivative using divideSeries, to find the percent difference from the previous data point.