Computing time difference with timezone in Series with one row gives wrong result #12290
Description
When there are only one row containing timestamps with timezone in DataFrame, computing time difference between columns gives incorrect result - always '0 days':
In [133]: import pandas as pd In [134]: df = pd.DataFrame(columns=['s', 'f']) In [135]: df.s = [pd.Timestamp('2016-02-08 13:43:14.605000', tz='America/Sao_Paulo')] In [136]: df.f = [pd.Timestamp('2016-02-10 13:43:14.605000', tz='America/Sao_Paulo')] In [137]: df Out[137]: s f 0 2016-02-08 13:43:14.605000-02:00 2016-02-10 13:43:14.605000-02:00 In [138]: df.f - df.s # should give '2 days' Out[138]: 0 0 days Name: f, dtype: timedelta64[ns] In [139]: df.s - df.f # should give '-2 days' Out[139]: 0 0 days Name: s, dtype: timedelta64[ns] If there are more than one row, result is correct:
In [140]: import pandas as pd In [141]: df = pd.DataFrame(columns=['s', 'f']) In [142]: df.s = [pd.Timestamp('2016-02-08 13:43:14.605000', tz='America/Sao_Paulo'), pd.Timestamp('2016-02-08 13:43:14.605000', tz='America/Sao_P aulo')] In [143]: df.f = [pd.Timestamp('2016-02-10 13:43:14.605000', tz='America/Sao_Paulo'), pd.Timestamp('2016-02-11 15:43:14.605000', tz='America/Sao_P aulo')] In [144]: df Out[144]: s f 0 2016-02-08 13:43:14.605000-02:00 2016-02-10 13:43:14.605000-02:00 1 2016-02-08 13:43:14.605000-02:00 2016-02-11 15:43:14.605000-02:00 In [145]: df.f - df.s Out[145]: 0 2 days 00:00:00 1 3 days 02:00:00 Name: f, dtype: timedelta64[ns] One row containing timestamps in naive datetime also gives correct result:
In [147]: import pandas as pd In [148]: df = pd.DataFrame(columns=['s', 'f']) In [149]: df.s = [pd.Timestamp('2016-02-08 13:43:14.605000')] In [150]: df.f = [pd.Timestamp('2016-02-10 13:43:14.605000')] In [151]: df Out[151]: s f 0 2016-02-08 13:43:14.605 2016-02-10 13:43:14.605 In [152]: df.f - df.s Out[152]: 0 2 days dtype: timedelta64[ns] Installed versions:
In [162]: pd.show_versions() INSTALLED VERSIONS ------------------ commit: None python: 2.7.6.final.0 python-bits: 64 OS: Linux OS-release: 3.13.0-49-generic machine: x86_64 processor: x86_64 byteorder: little LC_ALL: None LANG: en_US.UTF-8 pandas: 0.17.1 nose: None pip: 8.0.2 setuptools: 18.2 Cython: None numpy: 1.10.4 scipy: None statsmodels: None IPython: 4.0.3 sphinx: None patsy: None dateutil: 2.4.2 pytz: 2015.7 blosc: None bottleneck: None tables: None numexpr: None matplotlib: None openpyxl: None xlrd: None xlwt: None xlsxwriter: None lxml: None bs4: None html5lib: None httplib2: 0.9.2 apiclient: 1.4.2 sqlalchemy: None pymysql: None psycopg2: 2.6.1 (dt dec pq3 ext lo64) Jinja2: None