BUG: .describe() doesn't work for EAs #61707
Description
Pandas version checks
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Reproducible Example
import pandas as pd, pint_pandas
s = pd.Series([1, 2, 3], dtype='pint[kg]')
s.describe()
DimensionalityError Traceback (most recent call last)
...Issue Description
Series.describe sets the dtype for the results to Float64Dtype when the input is an EA. pint's Quantity
cannot be casted to Float64Dtype.
pandas/pandas/core/methods/describe.py
Line 255 in 35b0d1d
Expected Behavior
.describe should return a Series of objectdtype, or the dtype of the EA
Installed Versions
Replace this line with the output of pd.show_versions()
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kernelism commentedon Jun 26, 2025
take
andrewgsavage commentedon Jun 26, 2025
kernelism commentedon Jun 29, 2025
@andrewgsavage I’ve been exploring the codebase (still new here), and my initial thought is to check if the list of calculated statistics contains multiple types. If so, setting
dtype=Nonewould cause the result to be a Series with object dtype, which should resolve the issue. Does that sound right?andrewgsavage commentedon Jun 29, 2025
I think that is a good solution. I wonder how it would deal with an Series with int dtype. Should that give objects or float dtype?, since mean would give a float while mean would give int
kernelism commentedon Jun 30, 2025
In that case, it would never go into the if block checking if the series dtype is EA. It would automatically get a float type based on existing logic. Our fix would only pertain to EAs.
pandas/pandas/core/methods/describe.py
Lines 256 to 258 in 35b0d1d
Should I open a PR?