v0.14.1.txt

.. _whatsnew_0141:

v0.14.1 (???)
-------------

This is a minor release from 0.14.0 and includes a small number of API changes, several new features,
enhancements, and performance improvements along with a large number of bug fixes. We recommend that all
users upgrade to this version.

- Highlights include:

  - Support for ``dateutil`` timezones. See :ref:`Here <whatsnew_0141.enhancements>`

- :ref:`Other Enhancements <whatsnew_0141.enhancements>`

- :ref:`API Changes <whatsnew_0141.api>`

- :ref:`Performance Improvements <whatsnew_0141.performance>`

- :ref:`Prior Deprecations <whatsnew_0141.prior_deprecations>`

- :ref:`Deprecations <whatsnew_0141.deprecations>`

- :ref:`Bug Fixes <whatsnew_0141.bug_fixes>`

.. _whatsnew_0141.api:

API changes
~~~~~~~~~~~






- All ``offsets`` suppports ``normalize`` keyword to specify whether ``offsets.apply``, ``rollforward`` and ``rollback`` resets time (hour, minute, etc) or not (default ``False``, preserves time) (:issue:`7156`)


  .. ipython:: python

   import pandas.tseries.offsets as offsets

   day = offsets.Day()
   day.apply(Timestamp('2014-01-01 09:00'))

   day = offsets.Day(normalize=True)
   day.apply(Timestamp('2014-01-01 09:00'))

- Improved inference of datetime/timedelta with mixed null objects. Regression from 0.13.1 in interpretation of an object Index
  with all null elements (:issue:`7431`)

- Openpyxl now raises a ValueError on construction of the openpyxl writer
  instead of warning on pandas import (:issue:`7284`).

- For ``StringMethods.extract``, when no match is found, the result - only
  containing ``NaN`` values - now also has ``dtype=object`` instead of
  ``float`` (:issue:`7242`)

- `StringMethods`` now work on empty Series (:issue:`7242`)
- ``Period`` objects no longer raise a ``TypeError`` when compared using ``==``
  with another object that *isn't* a ``Period``. See :issue:`7376`. Instead
  when comparing a ``Period`` with another object using ``==`` if the other
  object isn't a ``Period`` ``False`` is returned.

.. _whatsnew_0141.prior_deprecations:

Prior Version Deprecations/Changes
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

There are no prior version deprecations that are taking effect as of 0.14.1.

.. _whatsnew_0141.deprecations:

Deprecations
~~~~~~~~~~~~

There are no deprecations that are taking effect as of 0.14.1.

.. _whatsnew_0141.enhancements:

Enhancements
~~~~~~~~~~~~






















- Tests for basic reading of public S3 buckets now exist (:issue:`7281`).
- ``read_html`` now sports an ``encoding`` argument that is passed to the
  underlying parser library. You can use this to read non-ascii encoded web
  pages (:issue:`7323`).

- Support for dateutil timezones, which can now be used in the same way as
  pytz timezones across pandas. (:issue:`4688`)

  .. ipython:: python

   rng = date_range('3/6/2012 00:00', periods=10, freq='D',
                    tz='dateutil/Europe/London')
   rng.tz

  See :ref:`the docs <timeseries.timezone>`.

- Implemented ``sem`` (standard error of the mean) operation for ``Series``,
  ``DataFrame``, ``Panel``, and ``Groupby`` (:issue:`6897`)
- Add ``nlargest`` and ``nsmallest`` to the ``Series`` ``groupby`` whitelist,
  which means you can now use these methods on a ``SeriesGroupBy`` object
  (:issue:`7053`).



- All offsets ``apply``, ``rollforward`` and ``rollback`` can now handle ``np.datetime64``, previously results in ``ApplyTypeError`` (:issue:`7452`)




.. _whatsnew_0141.performance:

Performance
~~~~~~~~~~~
- Improvements in dtype inference for numeric operations involving yielding performance gains for dtypes: ``int64``, ``timedelta64``, ``datetime64`` (:issue:`7223`)
- Improvements in Series.transform for signifcant performance gains (:issue`6496`)







Experimental
~~~~~~~~~~~~

There are no experimental changes in 0.14.1

.. _whatsnew_0141.bug_fixes:

Bug Fixes
~~~~~~~~~












- Bug in ``DatetimeIndex.insert`` doesn't preserve ``name`` and ``tz`` (:issue:`7299`)
- Bug in ``DatetimeIndex.asobject`` doesn't preserve ``name`` (:issue:`7299`)
- Bug in multi-index slicing with datetimelike ranges (strings and Timestamps), (:issue:`7429`)
- Bug in ``Index.min`` and ``max`` doesn't handle ``nan`` and ``NaT`` properly (:issue:`7261`)
- Bug in ``resample`` where ``fill_method`` was ignored if you passed ``how`` (:issue:`7261`)
- Bug in ``TimeGrouper`` doesn't exclude column specified by ``key`` (:issue:`7227`)
- Bug in ``DataFrame`` and ``Series`` bar and barh plot raises ``TypeError`` when ``bottom``
  and ``left`` keyword is specified (:issue:`7226`)
- BUG in ``DataFrame.hist`` raises ``TypeError`` when it contains non numeric column (:issue:`7277`)
- BUG in ``Index.delete`` does not preserve ``name`` and ``freq`` attributes (:issue:`7302`)
- Bug in ``DataFrame.query()``/``eval`` where local string variables with the @
  sign were being treated as temporaries attempting to be deleted
  (:issue:`7300`).
- Bug in ``Float64Index`` which didn't allow duplicates (:issue:`7149`).
- Bug in ``DataFrame.replace()`` where truthy values were being replaced
  (:issue:`7140`).
- Bug in ``StringMethods.extract()`` where a single match group Series
  would use the matcher's name instead of the group name (:issue:`7313`).
- Bug in ``isnull()`` when ``mode.use_inf_as_null == True`` where isnull
  wouldn't test ``True`` when it encountered an ``inf``/``-inf``
  (:issue:`7315`).
- Bug in inferred_freq results in None for eastern hemisphere timezones (:issue:`7310`)
- Bug in ``Easter`` returns incorrect date when offset is negative (:issue:`7195`)
- Bug in broadcasting with ``.div``, integer dtypes and divide-by-zero (:issue:`7325`)
- Bug in ``CustomBusinessDay.apply`` raiases ``NameError`` when ``np.datetime64`` object is passed (:issue:`7196`)
- Bug in ``MultiIndex.append``, ``concat`` and ``pivot_table`` don't preserve timezone (:issue:`6606`)
- Bug in ``.loc`` with a list of indexers on a single-multi index level (that is not nested) (:issue:`7349`)
- Bug in ``Series.map`` when mapping a dict with tuple keys of different lengths (:issue:`7333`)
- Bug all ``StringMethods`` now work on empty Series (:issue:`7242`)
- Fix delegation of `read_sql` to `read_sql_query` when query does not contain
 'select' (:issue:`7324`).
- Bug where a string column name assignment to a ``DataFrame`` with a
  ``Float64Index`` raised a ``TypeError`` during a call to ``np.isnan``
  (:issue:`7366`).
- Bug where ``NDFrame.replace()`` didn't correctly replace objects with
  ``Period`` values (:issue:`7379`).
- Bug in ``.ix`` getitem should always return a Series (:issue:`7150`)
- Bug in multi-index slicing with incomplete indexers (:issue:`7399`)
- Bug in multi-index slicing with a step in a sliced level (:issue:`7400`)
- Bug where negative indexers in ``DatetimeIndex`` were not correctly sliced
  (:issue:`7408`)
- Bug where ``NaT`` wasn't repr'd correctly in a ``MultiIndex`` (:issue:`7406`,
  :issue:`7409`).
- Bug where bool objects were converted to ``nan`` in ``convert_objects``
  (:issue:`7416`).
- Bug in ``quantile`` ignoring the axis keyword argument (:issue`7306`)
- Bug where ``nanops._maybe_null_out`` doesn't work with complex numbers
  (:issue:`7353`)
- Bug in several ``nanops`` functions when ``axis==0`` for
  1-dimensional ``nan`` arrays (:issue:`7354`)
- Bug where ``nanops.nanmedian`` doesn't work when ``axis==None``
  (:issue:`7352`)
- Bug where ``nanops._has_infs`` doesn't work with many dtypes
  (:issue:`7357`)
- Bug in ``StataReader.data`` where reading a 0-observation dta failed (:issue:`7369`)





- BUG in ``resample`` raises ``ValueError`` when target contains ``NaT`` (:issue:`7227`)



- Bug in ``Index.astype(float)`` where it would return an ``object`` dtype
  ``Index`` (:issue:`7464`).



- Bug in non-monotonic ``Index.union`` may preserve ``name`` incorrectly (:issue:`7458`)
- Bug in ``DatetimeIndex.intersection`` doesn't preserve timezone (:issue:`4690`)