MultiIndex.from_tuples returns an Index when all tuples are length 1 (original) (raw)

In [1]: import pandas as pd In [2]: pd.MultiIndex.from_tuples([('a',), ('b',)]) Out[2]: Index(['a', 'b'], dtype='object')

This should return a MultiIndex I think, like

Out[5]: MultiIndex(levels=[['a', 'b']], labels=[[0, 1]])

Well, pd.MultiIndex([['a', 'b']], [[0, 1]]) returns the same thing as from_tuples (an index) so maybe this is intentional.

Trying to figure out if this is intentional or not (this came up in my categorical dtype refactor).