mars.dataframe.Series.expanding#

Series.expanding(min_periods=1, center=False, axis=0)#

Provide expanding transformations.

Parameters

  • min_periods (int, default 1) –

  • value (Minimum number of observations in window required to have a) –

  • NA). ((otherwise result is) –

  • center (bool, default False) –

  • window. (Set the labels at the center of the) –

  • axis (int or str, default 0) –

Return type

a Window sub-classed for the particular operation

See also

rolling

Provides rolling window calculations.

ewm

Provides exponential weighted functions.

Notes

By default, the result is set to the right edge of the window. This can be changed to the center of the window by setting center=True.

Examples

>>> import numpy as np
>>> import mars.dataframe as md
>>> df = md.DataFrame({'B': [0, 1, 2, np.nan, 4]})
>>> df.execute()
     B
0  0.0
1  1.0
2  2.0
3  NaN
4  4.0
>>> df.expanding(2).sum().execute()
     B
0  NaN
1  1.0
2  3.0
3  3.0
4  7.0