pandas-dev/pandas (original) (raw)

import pandas as pd pd.Series([0, 0], dtype='object').argmax()

I was doing action = state_action.idxmax() where state_action was of type 'pandas.core.series.Series'. When I run in 0.21.0, it gives the following error:

File "/usr/local/lib/python3.5/dist-packages/pandas/core/series.py", line 1357, in idxmax
i = nanops.nanargmax(_values_from_object(self), skipna=skipna)
File "/usr/local/lib/python3.5/dist-packages/pandas/core/nanops.py", line 74, in _f
raise TypeError(msg.format(name=f.name.replace('nan', '')))
TypeError: reduction operation 'argmax' not allowed for this dtype

However, when I downgraded to pandas 0.20.3, it worked just fine. You might wanna look into this. :)