.. _whatsnew_0192: Version 0.19.2 (December 24, 2016) ---------------------------------- {{ header }} .. ipython:: python :suppress: from pandas import * # noqa F401, F403 This is a minor bug-fix release in the 0.19.x series and includes some small regression fixes, bug fixes and performance improvements. We recommend that all users upgrade to this version. Highlights include: - Compatibility with Python 3.6 - Added a `Pandas Cheat Sheet `__. (:issue:`13202`). .. contents:: What's new in v0.19.2 :local: :backlinks: none .. _whatsnew_0192.enhancements: Enhancements ~~~~~~~~~~~~ The ``pd.merge_asof()``, added in 0.19.0, gained some improvements: - ``pd.merge_asof()`` gained ``left_index``/``right_index`` and ``left_by``/``right_by`` arguments (:issue:`14253`) - ``pd.merge_asof()`` can take multiple columns in ``by`` parameter and has specialized dtypes for better performance (:issue:`13936`) .. _whatsnew_0192.performance: Performance improvements ~~~~~~~~~~~~~~~~~~~~~~~~ - Performance regression with ``PeriodIndex`` (:issue:`14822`) - Performance regression in indexing with getitem (:issue:`14930`) - Improved performance of ``.replace()`` (:issue:`12745`) - Improved performance ``Series`` creation with a datetime index and dictionary data (:issue:`14894`) .. _whatsnew_0192.bug_fixes: Bug fixes ~~~~~~~~~ - Compat with python 3.6 for pickling of some offsets (:issue:`14685`) - Compat with python 3.6 for some indexing exception types (:issue:`14684`, :issue:`14689`) - Compat with python 3.6 for deprecation warnings in the test suite (:issue:`14681`) - Compat with python 3.6 for Timestamp pickles (:issue:`14689`) - Compat with ``dateutil==2.6.0``; segfault reported in the testing suite (:issue:`14621`) - Allow ``nanoseconds`` in ``Timestamp.replace`` as a kwarg (:issue:`14621`) - Bug in ``pd.read_csv`` in which aliasing was being done for ``na_values`` when passed in as a dictionary (:issue:`14203`) - Bug in ``pd.read_csv`` in which column indices for a dict-like ``na_values`` were not being respected (:issue:`14203`) - Bug in ``pd.read_csv`` where reading files fails, if the number of headers is equal to the number of lines in the file (:issue:`14515`) - Bug in ``pd.read_csv`` for the Python engine in which an unhelpful error message was being raised when multi-char delimiters were not being respected with quotes (:issue:`14582`) - Fix bugs (:issue:`14734`, :issue:`13654`) in ``pd.read_sas`` and ``pandas.io.sas.sas7bdat.SAS7BDATReader`` that caused problems when reading a SAS file incrementally. - Bug in ``pd.read_csv`` for the Python engine in which an unhelpful error message was being raised when ``skipfooter`` was not being respected by Python's CSV library (:issue:`13879`) - Bug in ``.fillna()`` in which timezone aware datetime64 values were incorrectly rounded (:issue:`14872`) - Bug in ``.groupby(..., sort=True)`` of a non-lexsorted MultiIndex when grouping with multiple levels (:issue:`14776`) - Bug in ``pd.cut`` with negative values and a single bin (:issue:`14652`) - Bug in ``pd.to_numeric`` where a 0 was not unsigned on a ``downcast='unsigned'`` argument (:issue:`14401`) - Bug in plotting regular and irregular timeseries using shared axes (``sharex=True`` or ``ax.twinx()``) (:issue:`13341`, :issue:`14322`). - Bug in not propagating exceptions in parsing invalid datetimes, noted in python 3.6 (:issue:`14561`) - Bug in resampling a ``DatetimeIndex`` in local TZ, covering a DST change, which would raise ``AmbiguousTimeError`` (:issue:`14682`) - Bug in indexing that transformed ``RecursionError`` into ``KeyError`` or ``IndexingError`` (:issue:`14554`) - Bug in ``HDFStore`` when writing a ``MultiIndex`` when using ``data_columns=True`` (:issue:`14435`) - Bug in ``HDFStore.append()`` when writing a ``Series`` and passing a ``min_itemsize`` argument containing a value for the ``index`` (:issue:`11412`) - Bug when writing to a ``HDFStore`` in ``table`` format with a ``min_itemsize`` value for the ``index`` and without asking to append (:issue:`10381`) - Bug in ``Series.groupby.nunique()`` raising an ``IndexError`` for an empty ``Series`` (:issue:`12553`) - Bug in ``DataFrame.nlargest`` and ``DataFrame.nsmallest`` when the index had duplicate values (:issue:`13412`) - Bug in clipboard functions on linux with python2 with unicode and separators (:issue:`13747`) - Bug in clipboard functions on Windows 10 and python 3 (:issue:`14362`, :issue:`12807`) - Bug in ``.to_clipboard()`` and Excel compat (:issue:`12529`) - Bug in ``DataFrame.combine_first()`` for integer columns (:issue:`14687`). - Bug in ``pd.read_csv()`` in which the ``dtype`` parameter was not being respected for empty data (:issue:`14712`) - Bug in ``pd.read_csv()`` in which the ``nrows`` parameter was not being respected for large input when using the C engine for parsing (:issue:`7626`) - Bug in ``pd.merge_asof()`` could not handle timezone-aware DatetimeIndex when a tolerance was specified (:issue:`14844`) - Explicit check in ``to_stata`` and ``StataWriter`` for out-of-range values when writing doubles (:issue:`14618`) - Bug in ``.plot(kind='kde')`` which did not drop missing values to generate the KDE Plot, instead generating an empty plot. (:issue:`14821`) - Bug in ``unstack()`` if called with a list of column(s) as an argument, regardless of the dtypes of all columns, they get coerced to ``object`` (:issue:`11847`) .. _whatsnew_0.19.2.contributors: Contributors ~~~~~~~~~~~~ .. contributors:: v0.19.1..v0.19.2