BUG: np.timedelta64 arithmetic appears buggy #4135
Description
Buggy timedelta arithmetic with np.timedelta64 in np 1.7.1
In [41]: s = Series([Timestamp('20130301'),Timestamp('20130228 23:00:00'),Timestamp('20130228 22:00:00'),Timestamp('20130228 21:00:00')]) In [42]: s Out[42]: 0 2013-03-01 00:00:00 1 2013-02-28 23:00:00 2 2013-02-28 22:00:00 3 2013-02-28 21:00:00 dtype: datetime64[ns] In [43]: s + timedelta(hours=1) Out[43]: 0 2013-03-01 01:00:00 1 2013-03-01 00:00:00 2 2013-02-28 23:00:00 3 2013-02-28 22:00:00 dtype: datetime64[ns] Should be the same as above
In [45]: s + np.timedelta64(1,'h') Out[45]: 0 2013-03-01 00:00:00.000000001 1 2013-02-28 23:00:00.000000001 2 2013-02-28 22:00:00.000000001 3 2013-02-28 21:00:00.000000001 dtype: datetime64[ns]