Backport PR #28073: DOC: Update whatsnew

Author: TomAugspurger

doc/source/whatsnew/v0.25.1.rst

@@ -1,57 +1,43 @@
 .. _whatsnew_0251:
 
-What's new in 0.25.1 (July XX, 2019)
-------------------------------------
+What's new in 0.25.1 (August 21, 2019)
+--------------------------------------
 
-Enhancements
-~~~~~~~~~~~~
-
-
-.. _whatsnew_0251.enhancements.other:
+These are the changes in pandas 0.25.1. See :ref:`release` for a full changelog
+including other versions of pandas.
 
-Other enhancements
-^^^^^^^^^^^^^^^^^^
+I/O and LZMA
+~~~~~~~~~~~~
 
--
--
--
+Some users may unknowingly have an incomplete Python installation lacking the `lzma` module from the standard library. In this case, `import pandas` failed due to an `ImportError` (:issue: `27575`).
+Pandas will now warn, rather than raising an `ImportError` if the `lzma` module is not present. Any subsequent attempt to use `lzma` methods will raise a `RuntimeError`.
+A possible fix for the lack of the `lzma` module is to ensure you have the necessary libraries and then re-install Python.
+For example, on MacOS installing Python with `pyenv` may lead to an incomplete Python installation due to unmet system dependencies at compilation time (like `xz`). Compilation will succeed, but Python might fail at run time. The issue can be solved by installing the necessary dependencies and then re-installing Python.
 
 .. _whatsnew_0251.bug_fixes:
 
 Bug fixes
 ~~~~~~~~~
 
-
 Categorical
 ^^^^^^^^^^^
 
-- Bug in :meth:`Categorical.fillna` would replace all values, not just those that are ``NaN`` (:issue:`26215`)
--
--
+- Bug in :meth:`Categorical.fillna` that would replace all values, not just those that are ``NaN`` (:issue:`26215`)
 
 Datetimelike
 ^^^^^^^^^^^^
+
 - Bug in :func:`to_datetime` where passing a timezone-naive :class:`DatetimeArray` or :class:`DatetimeIndex` and ``utc=True`` would incorrectly return a timezone-naive result (:issue:`27733`)
 - Bug in :meth:`Period.to_timestamp` where a :class:`Period` outside the :class:`Timestamp` implementation bounds (roughly 1677-09-21 to 2262-04-11) would return an incorrect :class:`Timestamp` instead of raising ``OutOfBoundsDatetime`` (:issue:`19643`)
--
--
-
-Timedelta
-^^^^^^^^^
-
--
--
--
 
 Timezones
 ^^^^^^^^^
 
 - Bug in :class:`Index` where a numpy object array with a timezone aware :class:`Timestamp` and ``np.nan`` would not return a :class:`DatetimeIndex` (:issue:`27011`)
--
--
 
 Numeric
 ^^^^^^^
+
 - Bug in :meth:`Series.interpolate` when using a timezone aware :class:`DatetimeIndex` (:issue:`27548`)
 - Bug when printing negative floating point complex numbers would raise an ``IndexError`` (:issue:`27484`)
 - Bug where :class:`DataFrame` arithmetic operators such as :meth:`DataFrame.mul` with a :class:`Series` with axis=1 would raise an ``AttributeError`` on :class:`DataFrame` larger than the minimum threshold to invoke numexpr (:issue:`27636`)
@@ -61,23 +47,11 @@ Conversion
 ^^^^^^^^^^
 
 - Improved the warnings for the deprecated methods :meth:`Series.real` and :meth:`Series.imag` (:issue:`27610`)
--
--
-
-Strings
-^^^^^^^
-
--
--
--
-
 
 Interval
 ^^^^^^^^
+
 - Bug in :class:`IntervalIndex` where `dir(obj)` would raise ``ValueError`` (:issue:`27571`)
--
--
--
 
 Indexing
 ^^^^^^^^
@@ -86,47 +60,34 @@ Indexing
 - Break reference cycle involving :class:`Index` and other index classes to allow garbage collection of index objects without running the GC. (:issue:`27585`, :issue:`27840`)
 - Fix regression in assigning values to a single column of a DataFrame with a ``MultiIndex`` columns (:issue:`27841`).
 - Fix regression in ``.ix`` fallback with an ``IntervalIndex`` (:issue:`27865`).
--
 
 Missing
 ^^^^^^^
 
-- Bug in :func:`pandas.isnull` or :func:`pandas.isna` when the input is a type e.g. `type(pandas.Series())` (:issue:`27482`)
--
--
-
-MultiIndex
-^^^^^^^^^^
-
--
--
--
+- Bug in :func:`pandas.isnull` or :func:`pandas.isna` when the input is a type e.g. ``type(pandas.Series())`` (:issue:`27482`)
 
 I/O
 ^^^
+
 - Avoid calling ``S3File.s3`` when reading parquet, as this was removed in s3fs version 0.3.0 (:issue:`27756`)
 - Better error message when a negative header is passed in :func:`pandas.read_csv` (:issue:`27779`)
-- Follow the ``min_rows`` display option (introduced in v0.25.0) correctly in the html repr in the notebook (:issue:`27991`).
--
+- Follow the ``min_rows`` display option (introduced in v0.25.0) correctly in the HTML repr in the notebook (:issue:`27991`).
 
 Plotting
 ^^^^^^^^
 
-- Added a pandas_plotting_backends entrypoint group for registering plot backends. See :ref:`extending.plotting-backends` for more (:issue:`26747`).
+- Added a ``pandas_plotting_backends`` entrypoint group for registering plot backends. See :ref:`extending.plotting-backends` for more (:issue:`26747`).
 - Fixed the re-instatement of Matplotlib datetime converters after calling
-  `pandas.plotting.deregister_matplotlib_converters()` (:issue:`27481`).
--
+  :meth:`pandas.plotting.deregister_matplotlib_converters` (:issue:`27481`).
 - Fix compatibility issue with matplotlib when passing a pandas ``Index`` to a plot call (:issue:`27775`).
--
 
 Groupby/resample/rolling
 ^^^^^^^^^^^^^^^^^^^^^^^^
 
 - Bug in :meth:`pandas.core.groupby.DataFrameGroupBy.transform` where applying a timezone conversion lambda function would drop timezone information (:issue:`27496`)
 - Bug in :meth:`pandas.core.groupby.GroupBy.nth` where ``observed=False`` was being ignored for Categorical groupers (:issue:`26385`)
 - Bug in windowing over read-only arrays (:issue:`27766`)
--
--
+- Fixed segfault in `pandas.core.groupby.DataFrameGroupBy.quantile` when an invalid quantile was passed (:issue:`27470`)
 
 Reshaping
 ^^^^^^^^^
@@ -139,39 +100,12 @@ Reshaping
 Sparse
 ^^^^^^
 
--
--
--
-
-
-Build Changes
-^^^^^^^^^^^^^
-
--
--
--
-
-ExtensionArray
-^^^^^^^^^^^^^^
-
--
--
--
+- Bug in reductions for :class:`Series` with Sparse dtypes (:issue:`27080`)
 
 Other
 ^^^^^
-- Bug in :meth:`Series.replace` and :meth:`DataFrame.replace` when replacing timezone-aware timestamps using a dict-like replacer (:issue:`27720`)
--
--
--
-
-I/O and LZMA
-~~~~~~~~~~~~
 
-Some users may unknowingly have an incomplete Python installation, which lacks the `lzma` module from the standard library. In this case, `import pandas` failed due to an `ImportError` (:issue: `27575`).
-Pandas will now warn, rather than raising an `ImportError` if the `lzma` module is not present. Any subsequent attempt to use `lzma` methods will raise a `RuntimeError`.
-A possible fix for the lack of the `lzma` module is to ensure you have the necessary libraries and then re-install Python.
-For example, on MacOS installing Python with `pyenv` may lead to an incomplete Python installation due to unmet system dependencies at compilation time (like `xz`). Compilation will succeed, but Python might fail at run time. The issue can be solved by installing the necessary dependencies and then re-installing Python.
+- Bug in :meth:`Series.replace` and :meth:`DataFrame.replace` when replacing timezone-aware timestamps using a dict-like replacer (:issue:`27720`)
 
 .. _whatsnew_0.251.contributors: