Cast to PeriodArray/PeriodIndex at a particular frequency.
Converts DatetimeArray/Index to PeriodArray/PeriodIndex.
One of pandas’ period aliases or an Period object. Will be inferred by default.
When converting a DatetimeArray/Index with non-regular values, so that a frequency cannot be inferred.
See also
PeriodIndexImmutable ndarray holding ordinal values.
DatetimeIndex.to_pydatetimeReturn DatetimeIndex as object.
Examples
>>> df = pd.DataFrame({"y": [1, 2, 3]},
... index=pd.to_datetime(["2000-03-31 00:00:00",
... "2000-05-31 00:00:00",
... "2000-08-31 00:00:00"]))
>>> df.index.to_period("M")
PeriodIndex(['2000-03', '2000-05', '2000-08'],
dtype='period[M]')
Infer the daily frequency
>>> idx = pd.date_range("2017-01-01", periods=2)
>>> idx.to_period()
PeriodIndex(['2017-01-01', '2017-01-02'],
dtype='period[D]')
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https://pandas.pydata.org/pandas-docs/version/2.3.0/reference/api/pandas.Series.dt.to_period.html