pandas.DataFrame.expanding — pandas 0.18.1 documentation (original) (raw)

min_periods : int, default None

Minimum number of observations in window required to have a value (otherwise result is NA).

freq : string or DateOffset object, optional (default None) (DEPRECATED)

Frequency to conform the data to before computing the statistic. Specified as a frequency string or DateOffset object.

center : boolean, default False

Set the labels at the center of the window.

axis : int, default 0