Skip to content

BUG: pandas Timestamp tz_localize and tz_convert do not preserve freq attribute #25247

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
jreback merged 14 commits into from
Feb 11, 2019
Merged

BUG: pandas Timestamp tz_localize and tz_convert do not preserve freq attribute #25247

Show file tree
Hide file tree
Changes from 6 commits
Commits
Show all changes
14 commits
Select commit Hold shift + click to select a range
bb5731d
fix bug
charlesdong1991 Feb 9, 2019
8910104
add frq
charlesdong1991 Feb 9, 2019
bdd8b2e
experiment
charlesdong1991 Feb 9, 2019
64b1a88
code change based on review
charlesdong1991 Feb 9, 2019
9fc0b0a
correct pytest msg
charlesdong1991 Feb 9, 2019
c65a35c
fix pep8
charlesdong1991 Feb 9, 2019
d4a1515
code change based on review
charlesdong1991 Feb 9, 2019
2734a3b
code change based on review
charlesdong1991 Feb 10, 2019
e514a23
fix test
charlesdong1991 Feb 10, 2019
89af164
fix test
charlesdong1991 Feb 10, 2019
45d7b01
fix test
charlesdong1991 Feb 10, 2019
6666ea5
fix linting error
charlesdong1991 Feb 10, 2019
d923ddf
fix linting
charlesdong1991 Feb 10, 2019
115b87c
move test
charlesdong1991 Feb 10, 2019
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
2 changes: 1 addition & 1 deletion doc/source/whatsnew/v0.25.0.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -93,7 +93,7 @@ Timezones
^^^^^^^^^

- Bug in :func:`to_datetime` with ``utc=True`` and datetime strings that would apply previously parsed UTC offsets to subsequent arguments (:issue:`24992`)
-
- Bug in :func:`tz_localize` and :func:`tz_convert` does not propagate freq if ``Timestamp`` is initiated with freq (:issue:`25241`)
Copy link
Copy Markdown
Member

@mroeschke mroeschke Feb 10, 2019

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

Could you specify Timestamp.tz_localize and Timestamp.tz_convert? Then you can remove the additional Timestamp towards the end.

Double back ticks around freq as well.

Copy link
Copy Markdown
Contributor Author

@charlesdong1991 charlesdong1991 Feb 10, 2019

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

done, thanks for your review! @mroeschke

-

Numeric
Expand Down
6 changes: 3 additions & 3 deletions pandas/_libs/tslibs/timestamps.pyx
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -1187,12 +1187,12 @@ class Timestamp(_Timestamp):
value = tz_localize_to_utc(np.array([self.value], dtype='i8'), tz,
ambiguous=ambiguous,
nonexistent=nonexistent)[0]
return Timestamp(value, tz=tz)
return Timestamp(value, tz=tz, freq=self.freq)
else:
if tz is None:
# reset tz
value = tz_convert_single(self.value, UTC, self.tz)
return Timestamp(value, tz=None)
return Timestamp(value, tz=tz, freq=self.freq)
else:
raise TypeError('Cannot localize tz-aware Timestamp, use '
'tz_convert for conversions')
Expand Down Expand Up @@ -1222,7 +1222,7 @@ class Timestamp(_Timestamp):
'tz_localize to localize')
else:
# Same UTC timestamp, different time zone
return Timestamp(self.value, tz=tz)
return Timestamp(self.value, tz=tz, freq=self.freq)

astimezone = tz_convert

Expand Down
7 changes: 7 additions & 0 deletions pandas/tests/scalar/timestamp/test_timestamp.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -780,6 +780,13 @@ def test_hash_equivalent(self):
stamp = Timestamp(datetime(2011, 1, 1))
assert d[stamp] == 5

def test_tz_convert_freq(self, tz_naive_fixture):
# GH25241
t1 = Timestamp('2019-01-01 10:00', freq='H')
assert t1.tz_localize(tz=tz_naive_fixture).freq == t1.freq
t2 = Timestamp('2019-01-02 12:00', tz='UTC', freq='T')
assert t2.tz_convert(tz='UTC') == t2
Copy link
Copy Markdown
Contributor

@nmusolino nmusolino Feb 9, 2019

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

I think you need to assert that the freq attributes are equal, as opposed to comparing the timestamps.

Timestamp freq values do not influence equality comparisons or hash values. Here's a quick example that shows this:

>>> t1 = pandas.Timestamp('2018-01-01 10:00', freq='H') 
>>> t2 = pandas.Timestamp('2018-01-01 10:00', freq='T') 
>>> t1 == t2
True
>>> t1.freq == t2.freq
False

Copy link
Copy Markdown
Contributor Author

@charlesdong1991 charlesdong1991 Feb 9, 2019

Choose a reason for hiding this comment

The reason will be displayed to describe this comment to others. Learn more.

ahh, nice catch!!

t1 = pd.Timestamp('2018-01-01 10:00', freq='H')
t2 = pd.Timestamp('2018-01-01 10:00')])

and t1 != t2! thanks! @nmusolino



class TestTimestampNsOperations(object):

Expand Down
3 changes: 2 additions & 1 deletion pandas/tests/series/indexing/test_indexing.py
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -114,7 +114,8 @@ def test_getitem_get(test_data):

# missing
d = test_data.ts.index[0] - BDay()
with pytest.raises(KeyError, match=r"Timestamp\('1999-12-31 00:00:00'\)"):
msg = r"Timestamp\('1999-12-31 00:00:00', freq='B'\)"
with pytest.raises(KeyError, match=msg):
test_data.ts[d]

# None
Expand Down