What’s new in 1.3.1 (July 25, 2021)

These are the changes in pandas 1.3.1. See Release notes for a full changelog including other versions of pandas.

Fixed regressions

• Pandas could not be built on PyPy (GH42355)

• DataFrame constructed with an older version of pandas could not be unpickled (GH42345)

• Performance regression in constructing a DataFrame from a dictionary of dictionaries (GH42248)

• Fixed regression in DataFrame.agg() dropping values when the DataFrame had an Extension Array dtype, a duplicate index, and axis=1 (GH42380)

• Fixed regression in DataFrame.astype() changing the order of noncontiguous data (GH42396)

• Performance regression in DataFrame in reduction operations requiring casting such as DataFrame.mean() on integer data (GH38592)

• Performance regression in DataFrame.to_dict() and Series.to_dict() when orient argument one of “records”, “dict”, or “split” (GH42352)

• Fixed regression in indexing with a list subclass incorrectly raising TypeError (GH42433, GH42461)

• Fixed regression in DataFrame.isin() and Series.isin() raising TypeError with nullable data containing at least one missing value (GH42405)

• Regression in concat() between objects with bool dtype and integer dtype casting to object instead of to integer (GH42092)

• Bug in Series constructor not accepting a dask.Array (GH38645)

• Fixed regression for SettingWithCopyWarning displaying incorrect stacklevel (GH42570)

• Fixed regression for merge_asof() raising KeyError when one of the by columns is in the index (GH34488)

• Fixed regression in to_datetime() returning pd.NaT for inputs that produce duplicated values, when cache=True (GH42259)

• Fixed regression in SeriesGroupBy.value_counts() that resulted in an IndexError when called on a Series with one row (GH42618)

Bug fixes

• Fixed bug in DataFrame.transpose() dropping values when the DataFrame had an Extension Array dtype and a duplicate index (GH42380)

• Fixed bug in DataFrame.to_xml() raising KeyError when called with index=False and an offset index (GH42458)

• Fixed bug in Styler.set_sticky() not handling index names correctly for single index columns case (GH42537)

• Fixed bug in DataFrame.copy() failing to consolidate blocks in the result (GH42579)

Contributors

A total of 17 people contributed patches to this release. People with a “+” by their names contributed a patch for the first time.

• Fangchen Li

• GYvan +

• Matthew Roeschke

• Matthew Zeitlin

• MeeseeksMachine

• Pandas Development Team

• Patrick Hoefler

• Richard Shadrach

• Shoham Debnath +

• Simon Hawkins

• Stephan Heßelmann +

• Stephen +

• Thomas Li

• Zheyuan +

• attack68

• jbrockmendel

• neelmraman +

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What’s new in 1.3.2 (August 15, 2021)

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What’s new in 1.3.0 (July 2, 2021)