From 00523967f1c101f13f21be1b3245c2ca842efbd5 Mon Sep 17 00:00:00 2001 From: Phillip Cloud Date: Sat, 7 Jun 2014 21:29:22 -0400 Subject: [PATCH] BUG/TST: test for groupby max nan subselection bug --- pandas/tests/test_groupby.py | 11 +++++++++++ 1 file changed, 11 insertions(+) diff --git a/pandas/tests/test_groupby.py b/pandas/tests/test_groupby.py index 4aae5dfea3982..1f1853186ac8a 100644 --- a/pandas/tests/test_groupby.py +++ b/pandas/tests/test_groupby.py @@ -4369,6 +4369,17 @@ def test_ops_general(self): exc.args += ('operation: %s' % op,) raise + def test_max_nan_bug(self): + raw = """,Date,app,File +2013-04-23,2013-04-23 00:00:00,,log080001.log +2013-05-06,2013-05-06 00:00:00,,log.log +2013-05-07,2013-05-07 00:00:00,OE,xlsx""" + df = pd.read_csv(StringIO(raw), parse_dates=[0]) + gb = df.groupby('Date') + r = gb[['File']].max() + e = gb['File'].max().to_frame() + tm.assert_frame_equal(r, e) + self.assertFalse(r['File'].isnull().any()) def assert_fp_equal(a, b): assert (np.abs(a - b) < 1e-12).all()