What’s new in 1.4.3 (June 23, 2022) — pandas 3.0.0rc0+33.g1fd184de2a documentation (original) (raw)

These are the changes in pandas 1.4.3. See Release notes for a full changelog including other versions of pandas.

Behavior of `concat` with empty or all-NA DataFrame columns#

The behavior change in version 1.4.0 to stop ignoring the data type of empty or all-NA columns with float or object dtype in concat()(Ignoring dtypes in concat with empty or all-NA columns) has been reverted (GH 45637).

Fixed regressions#

Fixed regression in DataFrame.replace() when the replacement value was explicitly None when passed in a dictionary to to_replace also casting other columns to object dtype even when there were no values to replace (GH 46634)
Fixed regression in DataFrame.to_csv() raising error when DataFrame contains extension dtype categorical column (GH 46297, GH 46812)
Fixed regression in representation of dtypes attribute of MultiIndex (GH 46900)
Fixed regression when setting values with DataFrame.loc() updating RangeIndex when index was set as new column and column was updated afterwards (GH 47128)
Fixed regression in DataFrame.fillna() and DataFrame.update() creating a copy when updating inplace (GH 47188)
Fixed regression in DataFrame.nsmallest() led to wrong results when the sorting column has np.nan values (GH 46589)
Fixed regression in read_fwf() raising ValueError when widths was specified with usecols (GH 46580)
Fixed regression in concat() not sorting columns for mixed column names (GH 47127)
Fixed regression in Groupby.transform() and Groupby.agg() failing with engine="numba" when the index was a MultiIndex (GH 46867)
Fixed regression in NaN comparison for Index operations where the same object was compared (GH 47105)
Fixed regression is Styler.to_latex() and Styler.to_html() where buf failed in combination with encoding (GH 47053)
Fixed regression in read_csv() with index_col=False identifying first row as index names when header=None (GH 46955)
Fixed regression in DataFrameGroupBy.agg() when used with list-likes or dict-likes and axis=1 that would give incorrect results; now raises NotImplementedError (GH 46995)
Fixed regression in DataFrame.resample() and DataFrame.rolling() when used with list-likes or dict-likes and axis=1 that would raise an unintuitive error message; now raises NotImplementedError (GH 46904)
Fixed regression in testing.assert_index_equal() when check_order=False and Index has extension or object dtype (GH 47207)
Fixed regression in read_excel() returning ints as floats on certain input sheets (GH 46988)
Fixed regression in DataFrame.shift() when axis is columns and fill_value is absent, freq is ignored (GH 47039)
Fixed regression in DataFrame.to_json() causing a segmentation violation when DataFrame is created with an index parameter of the type PeriodIndex (GH 46683)

Bug fixes#

Bug in pandas.eval(), DataFrame.eval() and DataFrame.query() where passing empty local_dict or global_dict was treated as passing None (GH 47084)
Most I/O methods no longer suppress OSError and ValueError when closing file handles (GH 47136)
Improving error message raised by DataFrame.from_dict() when passing an invalid orient parameter (GH 47450)

Other#

The minimum version of Cython needed to compile pandas is now 0.29.30 (GH 41935)

Contributors#

A total of 18 people contributed patches to this release. People with a “+” by their names contributed a patch for the first time.