What's new in 1.5.3 (December ??, 2022)

These are the changes in pandas 1.5.3. See :ref:`release` for a full changelog including other versions of pandas.

Fixed regressions

Fixed performance regression in :meth:`Series.isin` when values is empty (:issue:`49839`)
Fixed regression in :meth:`DataFrame.memory_usage` showing unnecessary FutureWarning when :class:`DataFrame` is empty (:issue:`50066`)
Fixed regression in :meth:`.DataFrameGroupBy.transform` when used with as_index=False (:issue:`49834`)
Enforced reversion of color as an alias for c and size as an alias for s in function :meth:`DataFrame.plot.scatter` (:issue:`49732`)
Fixed regression in :meth:`.SeriesGroupBy.apply` setting a name attribute on the result if the result was a :class:`DataFrame` (:issue:`49907`)
Fixed performance regression in setting with the :meth:`~DataFrame.at` indexer (:issue:`49771`)
Fixed regression in :func:`to_datetime` raising ValueError when parsing array of float containing np.nan (:issue:`50237`)

Bug in the Copy-on-Write implementation losing track of views when indexing a :class:`DataFrame` with another :class:`DataFrame` (:issue:`50630`)
Bug in :meth:`.Styler.to_excel` leading to error when unrecognized border-style (e.g. "hair") provided to Excel writers (:issue:`48649`)
Bug in :meth:`Series.quantile` emitting warning from NumPy when :class:`Series` has only NA values (:issue:`50681`)
Bug when chaining several :meth:`.Styler.concat` calls, only the last styler was concatenated (:issue:`49207`)
Fixed bug when instantiating a :class:`DataFrame` subclass inheriting from typing.Generic that triggered a UserWarning on python 3.11 (:issue:`49649`)
Bug in :func:`pivot_table` with NumPy 1.24 or greater when the :class:`DataFrame` columns has nested elements (:issue:`50342`)
Bug in :func:`pandas.testing.assert_series_equal` (and equivalent assert_ functions) when having nested data and using numpy >= 1.25 (:issue:`50360`)

Note

If you are using :meth:`DataFrame.to_sql`, :func:`read_sql`, :func:`read_sql_table`, or :func:`read_sql_query` with SQLAlchemy 1.4.46 or greater, you may see a sqlalchemy.exc.RemovedIn20Warning. These warnings can be safely ignored for the SQLAlchemy 1.4.x releases as pandas works toward compatibility with SQLAlchemy 2.0.

Reverted deprecation (:issue:`45324`) of behavior of :meth:`Series.__getitem__` and :meth:`Series.__setitem__` slicing with an integer :class:`Index`; this will remain positional (:issue:`49612`)

.. contributors:: v1.5.2..v1.5.3|HEAD