Pandas Series: expanding() function
Expanding transformations in Pandas
The expanding() function is used to provide expanding transformations.
Syntax:
Series.expanding(self, min_periods=1, center=False, axis=0)
Parameters:
| Name | Description | Type/Default Value | Required / Optional |
|---|---|---|---|
| min_periods | Minimum number of observations in window required to have a value (otherwise result is NA). | int Default Value : 1 |
Required |
| center | Set the labels at the center of the window. | bool |
Required |
| axis | If the axis is a MultiIndex (hierarchical), group by a particular level or levels. | nt or str |
Required |
Returns: a Window sub-classed for the particular operation
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.
Python-Pandas Code:
import numpy as np
import pandas as pd
df = pd.DataFrame({'Q': [0, 2, 4, np.nan, 6]})
df
Output:
Q
0 0.0
1 2.0
2 4.0
3 NaN
4 6.0
Python-Pandas Code:
import numpy as np
import pandas as pd
df = pd.DataFrame({'Q': [0, 2, 4, np.nan, 6]})
df.expanding(2).sum()
Output:
Q
0 NaN
1 2.0
2 6.0
3 6.0
4 12.0
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