Skip to main content
`Ctrl`+`K`

# What’s new in 1.4.4 (August 31, 2022)

These are the changes in pandas 1.4.4. See Release notes for a full changelog including other versions of pandas.

## Fixed regressions

- Fixed regression in `DataFrame.fillna()` not working on a `DataFrame` with a `MultiIndex` (GH 47649)

- Fixed regression in taking NULL `objects` from a `DataFrame` causing a segmentation violation. These NULL values are created by `numpy.empty_like()` (GH 46848)

- Fixed regression in `concat()` materializing the `Index` during sorting even if the `Index` was already sorted (GH 47501)

- Fixed regression in `concat()` or `merge()` handling of all-NaN ExtensionArrays with custom attributes (GH 47762)

- Fixed regression in calling bitwise numpy ufuncs (for example, `np.bitwise_and`) on Index objects (GH 46769)

- Fixed regression in `cut()` when using a `datetime64` IntervalIndex as bins (GH 46218)

- Fixed regression in `DataFrame.select_dtypes()` where `include="number"` included `BooleanDtype` (GH 46870)

- Fixed regression in `DataFrame.loc()` raising error when indexing with a `NamedTuple` (GH 48124)

- Fixed regression in `DataFrame.loc()` not updating the cache correctly after values were set (GH 47867)

- Fixed regression in `DataFrame.loc()` not aligning index in some cases when setting a `DataFrame` (GH 47578)

- Fixed regression in `DataFrame.loc()` setting a length-1 array like value to a single value in the DataFrame (GH 46268)

- Fixed regression when slicing with `DataFrame.loc()` with `DatetimeIndex` with a `DateOffset` object for its `freq` (GH 46671)

- Fixed regression in setting `None` or non-string value into a `string`-dtype Series using a mask (GH 47628)

- Fixed regression in updating a DataFrame column through Series `__setitem__` (using chained assignment) not updating column values inplace and using too much memory (GH 47172)

- Fixed regression in `DataFrame.select_dtypes()` returning a view on the original DataFrame (GH 48090)

- Fixed regression using custom Index subclasses (for example, used in xarray) with `reset_index()` or `Index.insert()` (GH 47071)

- Fixed regression in `intersection()` when the `DatetimeIndex` has dates crossing daylight savings time (GH 46702)

- Fixed regression in `merge()` throwing an error when passing a `Series` with a multi-level name (GH 47946)

- Fixed regression in `DataFrame.eval()` creating a copy when updating inplace (GH 47449)

- Fixed regression where getting a row using `DataFrame.iloc()` with `SparseDtype` would raise (GH 46406)

## Bug fixes

- The `FutureWarning` raised when passing arguments (other than `filepath_or_buffer`) as positional in `read_csv()` is now raised at the correct stacklevel (GH 47385)

- Bug in `DataFrame.to_sql()` when `method` was a `callable` that did not return an `int` and would raise a `TypeError` (GH 46891)

- Bug in `DataFrameGroupBy.value_counts()` where `subset` had no effect (GH 46383)

- Bug when getting values with `DataFrame.loc()` with a list of keys causing an internal inconsistency that could lead to a disconnect between `frame.at[x, y]` vs `frame[y].loc[x]` (GH 22372)

- Bug in the `Series.dt.strftime()` accessor return a float instead of object dtype Series for all-NaT input, which also causes a spurious deprecation warning (GH 45858)

## Other

- The minimum version of Cython needed to compile pandas is now `0.29.32` (GH 47978)

## Contributors

For contributors, please see /usr/share/doc/contributors_list.txt or https://github.com/pandas-dev/pandas/graphs/contributors