pydata/pandas — pull request #8151 by behzadnouri (2014-08-31 22:39:18+00:00)
Title: BUG: consistency between logical ops & type casts

Closes [#6528](https://github.com/pydata/pandas/issues/6528).
Currently series logical operations are bound to return a series with `dtype='bool'`. That being a good decision or not, it is good to have some internal consistency:

>>> a = pd.Series([nan, nan, nan])
>>> b = pd.Series([False, True, nan])
>>> a | b == b | a # no symmetry
0 True
1 False
2 True
dtype: bool
>>> a & b == a.astype(bool) & b.astype(bool)
0 True
1 False
2 False
dtype: bool