What’s new in 1.4.2 (April 2, 2022)#
These are the changes in pandas 1.4.2. See Release notes for a full changelog including other versions of pandas.
Fixed regressions#
Fixed regression in
DataFrame.drop()
andSeries.drop()
whenIndex
had extension dtype and duplicates (GH 45860)Fixed regression in
read_csv()
killing python process when invalid file input was given forengine="c"
(GH 45957)Fixed memory performance regression in
Series.fillna()
when called on aDataFrame
column withinplace=True
(GH 46149)Provided an alternative solution for passing custom Excel formats in
Styler.to_excel()
, which was a regression based on stricter CSS validation. Examples available in the documentation forStyler.format()
(GH 46152)Fixed regression in
DataFrame.replace()
when a replacement value was also a target for replacement (GH 46306)Fixed regression in
DataFrame.replace()
when the replacement value was explicitlyNone
when passed in a dictionary toto_replace
(GH 45601, GH 45836)Fixed regression when setting values with
DataFrame.loc()
losingMultiIndex
names ifDataFrame
was empty before (GH 46317)Fixed regression when rendering boolean datatype columns with
Styler()
(GH 46384)Fixed regression in
Groupby.rolling()
with a frequency window that would raise aValueError
even if the datetimes within each group were monotonic (GH 46061)
Bug fixes#
Fix some cases for subclasses that define their
_constructor
properties as general callables (GH 46018)Fixed “longtable” formatting in
Styler.to_latex()
whencolumn_format
is given in extended format (GH 46037)Fixed incorrect rendering in
Styler.format()
withhyperlinks="html"
when the url contains a colon or other special characters (GH 46389)Improved error message in
Rolling
whenwindow
is a frequency andNaT
is in the rolling axis (GH 46087)
Contributors#
A total of 15 people contributed patches to this release. People with a “+” by their names contributed a patch for the first time.
Daniel Schmidt
JHM Darbyshire
Jonas Haag
Jordan Hicks +
Joris Van den Bossche
Kian Eliasi +
Luke Manley
Marco Edward Gorelli
Matthew Roeschke
MeeseeksMachine
Pandas Development Team
Patrick Hoefler
Richard Shadrach
Simon Hawkins
jbrockmendel