BUG: DataFrame.min with skipna=True raises TypeError when column contains np.nan and datetime.date #61204
Description
Pandas version checks
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I have confirmed this bug exists on the latest version of pandas.
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I have confirmed this bug exists on the main branch of pandas.
Reproducible Example
import pandas as pd import numpy as np import datetime data = { "dates": [ np.nan, np.nan, datetime.date(2025, 1, 3), datetime.date(2025, 1, 4), ], } df = pd.DataFrame(data) df.min(axis=0)Issue Description
The issue arises when calling DataFrame.min(axis=0) with skipna=True (default) on a column containing a mix of np.nan and datetime.date. This results in a TypeError because np.nan (a float) cannot be compared with datetime.date.
File "C:\Users\45217950\Downloads\GitHub\irr-cloud\test.py", line 29, in <module> df.min(axis=0) File "C:\Users\45217950\Downloads\GitHub\irr-cloud\.venv\Lib\site-packages\pandas\core\frame.py", line 11643, in min result = super().min(axis, skipna, numeric_only, **kwargs) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\45217950\Downloads\GitHub\irr-cloud\.venv\Lib\site-packages\pandas\core\generic.py", line 12388, in min return self._stat_function( ^^^^^^^^^^^^^^^^^^^^ File "C:\Users\45217950\Downloads\GitHub\irr-cloud\.venv\Lib\site-packages\pandas\core\generic.py", line 12377, in _stat_function return self._reduce( ^^^^^^^^^^^^^ File "C:\Users\45217950\Downloads\GitHub\irr-cloud\.venv\Lib\site-packages\pandas\core\frame.py", line 11562, in _reduce res = df._mgr.reduce(blk_func) ^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\45217950\Downloads\GitHub\irr-cloud\.venv\Lib\site-packages\pandas\core\internals\managers.py", line 1500, in reduce nbs = blk.reduce(func) ^^^^^^^^^^^^^^^^ File "C:\Users\45217950\Downloads\GitHub\irr-cloud\.venv\Lib\site-packages\pandas\core\internals\blocks.py", line 404, in reduce result = func(self.values) ^^^^^^^^^^^^^^^^^ File "C:\Users\45217950\Downloads\GitHub\irr-cloud\.venv\Lib\site-packages\pandas\core\frame.py", line 11481, in blk_func return op(values, axis=axis, skipna=skipna, **kwds) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\45217950\Downloads\GitHub\irr-cloud\.venv\Lib\site-packages\pandas\core\nanops.py", line 147, in f result = alt(values, axis=axis, skipna=skipna, **kwds) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\45217950\Downloads\GitHub\irr-cloud\.venv\Lib\site-packages\pandas\core\nanops.py", line 404, in new_func result = func(values, axis=axis, skipna=skipna, mask=mask, **kwargs) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\45217950\Downloads\GitHub\irr-cloud\.venv\Lib\site-packages\pandas\core\nanops.py", line 1098, in reduction result = getattr(values, meth)(axis) ^^^^^^^^^^^^^^^^^^^^^^^^^^^ File "C:\Users\45217950\Downloads\GitHub\irr-cloud\.venv\Lib\site-packages\numpy\_core\_methods.py", line 48, in _amin return umr_minimum(a, axis, None, out, keepdims, initial, where) ^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^ TypeError: '<=' not supported between instances of 'float' and 'datetime.date' This issue is related to issue #61187, but the specific case here involves datetime.date (not datetime.datetime), which behaves differently in pandas.
Expected Behavior
dates 2025-01-03 dtype: object Installed Versions
INSTALLED VERSIONS
commit : 0691c5c
python : 3.12.7
python-bits : 64
OS : Windows
OS-release : 10
Version : 10.0.19045
machine : AMD64
processor : Intel64 Family 6 Model 85 Stepping 7, GenuineIntel
byteorder : little
LC_ALL : None
LANG : en_US.UTF-8
LOCALE : English_United States.1252
pandas : 2.2.3
numpy : 2.2.3
pytz : 2025.1
dateutil : 2.9.0
pip : 24.2
Cython : None
sphinx : None
IPython : None
adbc-driver-postgresql: None
adbc-driver-sqlite : None
bs4 : None
blosc : None
bottleneck : None
dataframe-api-compat : None
fastparquet : None
fsspec : None
html5lib : None
hypothesis : None
gcsfs : None
jinja2 : None
lxml.etree : None
matplotlib : None
numba : None
numexpr : None
odfpy : None
openpyxl : 3.1.5
pandas_gbq : 0.28.0
psycopg2 : None
pymysql : None
pyarrow : 19.0.1
pyreadstat : None
pytest : None
python-calamine : None
pyxlsb : None
s3fs : None
scipy : 1.15.2
sqlalchemy : None
tables : None
tabulate : None
xarray : None
xlrd : None
xlsxwriter : 3.2.2
zstandard : None
tzdata : 2025.1
qtpy : None
pyqt5 : None