pandas.core.window.rolling.Rolling.std — pandas 3.0.0.dev0+2123.ge2bd8e60f0 documentation (original) (raw)
Rolling.std(ddof=1, numeric_only=False, engine=None, engine_kwargs=None)[source]#
Calculate the rolling standard deviation.
Parameters:
ddofint, default 1
Delta Degrees of Freedom. The divisor used in calculations is N - ddof
, where N
represents the number of elements.
numeric_onlybool, default False
Include only float, int, boolean columns.
Added in version 1.5.0.
enginestr, default None
'cython'
: Runs the operation through C-extensions from cython.'numba'
: Runs the operation through JIT compiled code from numba.None
: Defaults to'cython'
or globally settingcompute.use_numba
Added in version 1.4.0.
engine_kwargsdict, default None
- For
'cython'
engine, there are no acceptedengine_kwargs
- For
'numba'
engine, the engine can acceptnopython
,nogil
andparallel
dictionary keys. The values must either beTrue
orFalse
. The defaultengine_kwargs
for the'numba'
engine is{'nopython': True, 'nogil': False, 'parallel': False}
Added in version 1.4.0.
Returns:
Series or DataFrame
Return type is the same as the original object with np.float64
dtype.
See also
Equivalent method for NumPy array.
Series.rolling
Calling rolling with Series data.
DataFrame.rolling
Calling rolling with DataFrames.
Series.std
Aggregating std for Series.
DataFrame.std
Aggregating std for DataFrame.
Notes
The default ddof
of 1 used in Series.std()
is different than the default ddof
of 0 in numpy.std().
A minimum of one period is required for the rolling calculation.
Examples
s = pd.Series([5, 5, 6, 7, 5, 5, 5]) s.rolling(3).std() 0 NaN 1 NaN 2 0.577350 3 1.000000 4 1.000000 5 1.154701 6 0.000000 dtype: float64