Call function producing a like-indexed Series on each group.
Return a Series with the transformed values.
To apply to each group. Should return a Series with the same index.
Examples
>>> s = pd.Series([1, 2],
... index=pd.date_range('20180101',
... periods=2,
... freq='1h'))
>>> s
2018-01-01 00:00:00 1
2018-01-01 01:00:00 2
Freq: h, dtype: int64
>>> resampled = s.resample('15min')
>>> resampled.transform(lambda x: (x - x.mean()) / x.std())
2018-01-01 00:00:00 NaN
2018-01-01 01:00:00 NaN
Freq: h, dtype: float64
© 2008–2011, AQR Capital Management, LLC, Lambda Foundry, Inc. and PyData Development Team
© 2011–2025, Open source contributors
Licensed under the 3-clause BSD License.
https://pandas.pydata.org/pandas-docs/version/2.3.0/reference/api/pandas.core.resample.Resampler.transform.html