def asfreq(self, freq=None, how: str = "E") -> "PeriodArray":
"""
Convert the Period Array/Index to the specified frequency `freq`.
Parameters
----------
freq : str
A frequency.
how : str {'E', 'S'}
Whether the elements should be aligned to the end
or start within pa period.
* 'E', 'END', or 'FINISH' for end,
* 'S', 'START', or 'BEGIN' for start.
January 31st ('END') vs. January 1st ('START') for example.
Returns
-------
Period Array/Index
Constructed with the new frequency.
Examples
--------
>>> pidx = pd.period_range('2010-01-01', '2015-01-01', freq='A')
>>> pidx
PeriodIndex(['2010', '2011', '2012', '2013', '2014', '2015'],
dtype='period[A-DEC]', freq='A-DEC')
>>> pidx.asfreq('M')
PeriodIndex(['2010-12', '2011-12', '2012-12', '2013-12', '2014-12',
'2015-12'], dtype='period[M]', freq='M')
>>> pidx.asfreq('M', how='S')
PeriodIndex(['2010-01', '2011-01', '2012-01', '2013-01', '2014-01',
'2015-01'], dtype='period[M]', freq='M')
"""
how = libperiod.validate_end_alias(how)
freq = Period._maybe_convert_freq(freq)
base1 = self.freq._period_dtype_code
base2 = freq._period_dtype_code
asi8 = self.asi8
# self.freq.n can't be negative or 0
end = how == "E"
if end:
ordinal = asi8 + self.freq.n - 1
else:
ordinal = asi8
new_data = period_asfreq_arr(ordinal, base1, base2, end)
if self._hasnans:
new_data[self._isnan] = iNaT
return type(self)(new_data, freq=freq)
def to_timestamp(self, freq=None, how: str = "start") -> DatetimeArray:
"""
Cast to DatetimeArray/Index.
Parameters
----------
freq : str or DateOffset, optional
Target frequency. The default is 'D' for week or longer,
'S' otherwise.
how : {'s', 'e', 'start', 'end'}
Whether to use the start or end of the time period being converted.
Returns
-------
DatetimeArray/Index
"""
from pandas.core.arrays import DatetimeArray
how = libperiod.validate_end_alias(how)
end = how == "E"
if end:
if freq == "B" or self.freq == "B":
# roll forward to ensure we land on B date
adjust = Timedelta(1, "D") - Timedelta(1, "ns")
return self.to_timestamp(how="start") + adjust
else:
adjust = Timedelta(1, "ns")
return (self + self.freq).to_timestamp(how="start") - adjust
if freq is None:
freq = self._dtype._get_to_timestamp_base()
base = freq
else:
freq = Period._maybe_convert_freq(freq)
base = freq._period_dtype_code
new_parr = self.asfreq(freq, how=how)
new_data = libperiod.periodarr_to_dt64arr(new_parr.asi8, base)
dta = DatetimeArray(new_data)
if self.freq.name == "B":
# See if we can retain BDay instead of Day in cases where
# len(self) is too small for infer_freq to distinguish between them
diffs = libalgos.unique_deltas(self.asi8)
if len(diffs) == 1:
diff = diffs[0]
if diff == self.freq.n:
dta._freq = self.freq
elif diff == 1:
dta._freq = self.freq.base
# TODO: other cases?
return dta
else:
return dta._with_freq("infer")
def to_timestamp(self, freq=None, how="start"):
"""
Cast to DatetimeArray/Index.
Parameters
----------
freq : str or DateOffset, optional
Target frequency. The default is 'D' for week or longer,
'S' otherwise.
how : {'s', 'e', 'start', 'end'}
Whether to use the start or end of the time period being converted.
Returns
-------
DatetimeArray/Index
"""
from pandas.core.arrays import DatetimeArray
how = libperiod.validate_end_alias(how)
end = how == "E"
if end:
if freq == "B" or self.freq == "B":
# roll forward to ensure we land on B date
adjust = Timedelta(1, "D") - Timedelta(1, "ns")
return self.to_timestamp(how="start") + adjust
else:
adjust = Timedelta(1, "ns")
return (self + self.freq).to_timestamp(how="start") - adjust
if freq is None:
base = self.freq._period_dtype_code
freq = libfrequencies.get_to_timestamp_base(base)
base = freq
else:
freq = Period._maybe_convert_freq(freq)
base = freq._period_dtype_code
new_data = self.asfreq(freq, how=how)
new_data = libperiod.periodarr_to_dt64arr(new_data.asi8, base)
return DatetimeArray(new_data)._with_freq("infer")
def asfreq(self, freq=None, how: str = "E") -> PeriodArray:
"""
Convert the {klass} to the specified frequency `freq`.
Equivalent to applying :meth:`pandas.Period.asfreq` with the given arguments
to each :class:`~pandas.Period` in this {klass}.
Parameters
----------
freq : str
A frequency.
how : str {{'E', 'S'}}, default 'E'
Whether the elements should be aligned to the end
or start within pa period.
* 'E', 'END', or 'FINISH' for end,
* 'S', 'START', or 'BEGIN' for start.
January 31st ('END') vs. January 1st ('START') for example.
Returns
-------
{klass}
The transformed {klass} with the new frequency.
See Also
--------
{other}.asfreq: Convert each Period in a {other_name} to the given frequency.
Period.asfreq : Convert a :class:`~pandas.Period` object to the given frequency.
Examples
--------
>>> pidx = pd.period_range('2010-01-01', '2015-01-01', freq='A')
>>> pidx
PeriodIndex(['2010', '2011', '2012', '2013', '2014', '2015'],
dtype='period[A-DEC]')
>>> pidx.asfreq('M')
PeriodIndex(['2010-12', '2011-12', '2012-12', '2013-12', '2014-12',
'2015-12'], dtype='period[M]')
>>> pidx.asfreq('M', how='S')
PeriodIndex(['2010-01', '2011-01', '2012-01', '2013-01', '2014-01',
'2015-01'], dtype='period[M]')
"""
how = libperiod.validate_end_alias(how)
freq = Period._maybe_convert_freq(freq)
base1 = self.freq._period_dtype_code
base2 = freq._period_dtype_code
asi8 = self.asi8
# self.freq.n can't be negative or 0
end = how == "E"
if end:
ordinal = asi8 + self.freq.n - 1
else:
ordinal = asi8
new_data = period_asfreq_arr(ordinal, base1, base2, end)
if self._hasnans:
new_data[self._isnan] = iNaT
return type(self)(new_data, freq=freq)