BUG: GroupBy.value_counts sorting order by rhshadrach · Pull Request #56016 · pandas-dev/pandas (original) (raw)

Thanks - good call. I added a test and found a bug calling .sortlevel() in the categorical section. But the categorical behavior is still buggy here; namely

multi_index, _ = MultiIndex.from_product(
levels_list, names=[ping.name for ping in groupings]
).sortlevel()

is constructing the index by taking the cartesian product across all groupings; it should only be doing this for the categorical variables. That's not an easy fix, but will be handled in #55738 where we can just remove that whole block of code.