pandas.core.window.Expanding.apply

Expanding.apply(self, func, raw=None, args=(), kwargs={})

The expanding function’s apply function.

Parameters:

func : function

Must produce a single value from an ndarray input if raw=True or a single value from a Series if raw=False.

raw : bool, default None

• False : passes each row or column as a Series to the function.
• True or None : the passed function will receive ndarray objects instead. If you are just applying a NumPy reduction function this will achieve much better performance.

The raw parameter is required and will show a FutureWarning if not passed. In the future raw will default to False.

New in version 0.23.0.

*args, **kwargs

Arguments and keyword arguments to be passed into func.

Returns:

Series or DataFrame

Return type is determined by the caller.

See also

Series.expanding

Series expanding.

DataFrame.expanding

DataFrame expanding.