Whats new in 0.24.1 (February 3, 2019)

Warning

The 0.24.x series of releases will be the last to support Python 2. Future feature releases will support Python 3 only. See Plan for dropping Python 2.7 (opens new window) for more.

These are the changes in pandas 0.24.1. See Release Notes for a full changelog including other versions of pandas. See What’s new in 0.24.0 (January 25, 2019) for the 0.24.0 changelog.

API changes

Changing the sort parameter for Index set operations

The default sort value for Index.union() (opens new window) has changed from True to None (GH24959 (opens new window)). The default behavior, however, remains the same: the result is sorted, unless

1. self and other are identical
2. self or other is empty
3. self or other contain values that can not be compared (a RuntimeWarning is raised).

This change will allow sort=True to mean “always sort” in a future release.

The same change applies to Index.difference() (opens new window) and Index.symmetric_difference() (opens new window), which would not sort the result when the values could not be compared.

The sort option for Index.intersection() (opens new window) has changed in three ways.

1. The default has changed from True to False, to restore the pandas 0.23.4 and earlier behavior of not sorting by default.
2. The behavior of sort=True can now be obtained with sort=None. This will sort the result only if the values in self and other are not identical.
3. The value sort=True is no longer allowed. A future version of pandas will properly support sort=True meaning “always sort”.

Fixed regressions

• Fixed regression in DataFrame.to_dict() (opens new window) with records orient raising an AttributeError when the DataFrame contained more than 255 columns, or wrongly converting column names that were not valid python identifiers (GH24939 (opens new window), GH24940 (opens new window)).
• Fixed regression in read_sql() (opens new window) when passing certain queries with MySQL/pymysql (GH24988 (opens new window)).
• Fixed regression in Index.intersection (opens new window) incorrectly sorting the values by default (GH24959 (opens new window)).
• Fixed regression in merge() (opens new window) when merging an empty DataFrame with multiple timezone-aware columns on one of the timezone-aware columns (GH25014 (opens new window)).
• Fixed regression in Series.rename_axis() (opens new window) and DataFrame.rename_axis() (opens new window) where passing None failed to remove the axis name (GH25034 (opens new window))
• Fixed regression in to_timedelta() (opens new window) with box=False incorrectly returning a datetime64 object instead of a timedelta64 object (GH24961 (opens new window))
• Fixed regression where custom hashable types could not be used as column keys in DataFrame.set_index() (opens new window) (GH24969 (opens new window))

Bug fixes

Reshaping

• Bug in DataFrame.groupby() (opens new window) with Grouper (opens new window) when there is a time change (DST) and grouping frequency is '1d' (GH24972 (opens new window))

Visualization

• Fixed the warning for implicitly registered matplotlib converters not showing. See Restore Matplotlib datetime converter registration for more (GH24963 (opens new window)).

Other

• Fixed AttributeError when printing a DataFrame’s HTML repr after accessing the IPython config object (GH25036 (opens new window))

Contributors

A total of 7 people contributed patches to this release. People with a “+” by their names contributed a patch for the first time.

• Alex Buchkovsky
• Roman Yurchak
• h-vetinari
• jbrockmendel
• Jeremy Schendel
• Joris Van den Bossche
• Tom Augspurger