BUG: GH3461 Fix sorting in a frame with a list of columns which contains datetime64

[jreback]

closes #3461

[dougvk]

Hello, I just built pandas from source, and received this error on running unit tests:

FAIL: test_sort_datetimes (pandas.tests.test_frame.TestDataFrame)
----------------------------------------------------------------------
Traceback (most recent call last):
  File "/Users/_/__/lib/python2.7/site-packages/pandas-0.11.1.dev_3406a54-py2.7-macosx-10.6-intel.egg/pandas/tests/test_frame.py", line 8473, in test_sort_datetimes
    assert_frame_equal(df1,df2)
  File "/Users/_/__/lib/python2.7/site-packages/pandas-0.11.1.dev_3406a54-py2.7-macosx-10.6-intel.egg/pandas/util/testing.py", line 230, in assert_frame_equal
    assert(left.index.equals(right.index))
AssertionError

----------------------------------------------------------------------
Ran 3428 tests in 106.337s

FAILED (SKIP=129, failures=1)

I was wondering if I might have an outdated dependency. As I intend to use DataFrames, I'm a little disturbed by this failed unit test.

[jtratner]

I get this error every time I run my own test suite. I've been ignoring it
because it passes in Travis and I never handle datetimes. That said, I ran
a test script over recent commits: the error occurs in every commit
starting from the one that merged this issue (pandas@2842383). I'm using
OSX 10.8 and get this error - maybe it's a mac thing?

On Thu, Jun 20, 2013 at 10:31 AM, Doug von Kohorn
[email protected]:

Hello, I just built pandas from source, and received this error on running
unit tests:

FAIL: test_sort_datetimes (pandas.tests.test_frame.TestDataFrame)

Traceback (most recent call last):
File "/Users//__/lib/python2.7/site-packages/pandas-0.11.1.dev_3406a54-py2.7-macosx-10.6-intel.egg/pandas/tests/test_frame.py", line 8473, in test_sort_datetimes
assert_frame_equal(df1,df2)
File "/Users//__/lib/python2.7/site-packages/pandas-0.11.1.dev_3406a54-py2.7-macosx-10.6-intel.egg/pandas/util/testing.py", line 230, in assert_frame_equal
assert(left.index.equals(right.index))
AssertionError

---

Ran 3428 tests in 106.337s

FAILED (SKIP=129, failures=1)

I was wondering if I might have an outdated dependency. As I intend to use
DataFrames, I'm a little disturbed by this failed unit test.

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Reply to this email directly or view it on GitHubhttps://github.com//pull/3464#issuecomment-19756711
.

[jreback]

interestingly see #3902 seems
that some int64 values on macos are different
than everyone else in tr world

I'll bet that thr value for NaT is corrupted

[jtratner]

I'd be happy to place around with this, but I can't find where in the numpy
docs/source NaT is defined, etc. Any tips on where to look?

On Thu, Jun 20, 2013 at 11:00 AM, jreback [email protected] wrote:

interestingly see #3902 https://github.com/pydata/pandas/issues/3902seems
that some int64 values on macos are different
than everyone else in tr world

I'll bet that thr value for NaT is corrupted

—
Reply to this email directly or view it on GitHubhttps://github.com//pull/3464#issuecomment-19758856
.

[jreback]

let's make a new issue about this....

pandas/src/numpy_helper.h.....get_nat

[jreback]

this is copied from #3902

and ONLY true on mac (AFAIK)

the wraparound is troubling.....

In [1]: pd.Timestamp(np.iinfo(np.int64).max)
Out[1]: Timestamp('2262-04-11 23:47:16.854775807', tz=None)

In [2]: pd.Timestamp(np.iinfo(np.int64).min)
Out[2]: NaT

In [3]: pd.Timestamp(np.iinfo(np.int64).min + 1)
Out[3]: Timestamp('2262-04-10 00:12:43.145224193', tz=None)