pyspark.pandas.window.Expanding.min

Expanding.min() → FrameLike

Calculate the expanding minimum.

Note

the current implementation of this API uses Spark’s Window without specifying partition specification. This leads to move all data into single partition in single machine and could cause serious performance degradation. Avoid this method against very large dataset.

Returns
Series or DataFrame

Returned object type is determined by the caller of the expanding calculation.

See also

Series.expanding

Calling object with a Series.

DataFrame.expanding

Calling object with a DataFrame.

Series.min

Similar method for Series.

DataFrame.min

Similar method for DataFrame.

Examples

Performing a expanding minimum with a window size of 3.

>>> s = ps.Series([4, 3, 5, 2, 6])
>>> s.expanding(3).min()
0    NaN
1    NaN
2    3.0
3    2.0
4    2.0
dtype: float64