pandas.expanding_apply¶
- pandas.expanding_apply(arg, func, min_periods=1, freq=None, center=False, time_rule=None)¶
Generic expanding function application
Parameters : arg : Series, DataFrame
func : function
Must produce a single value from an ndarray input
min_periods : int
Minimum number of observations in window required to have a value
freq : None or string alias / date offset object, default=None
Frequency to conform to before computing statistic
center : boolean, default False
Whether the label should correspond with center of window
time_rule : Legacy alias for freq
Returns : y : type of input argument