Skip to content

Update whats-new for v2026.01.0 release #11109

New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Merged
dcherian merged 4 commits into from
Jan 28, 2026
Merged

Update whats-new for v2026.01.0 release #11109

Show file tree
Hide file tree
Changes from all commits
Commits
Show all changes
4 commits
Select commit Hold shift + click to select a range
d9f5a65
Prep whats-new for v2026.01.0 release
dcherian Jan 28, 2026
a6d2f85
tweak
dcherian Jan 28, 2026
eea7b61
more cleanup
dcherian Jan 28, 2026
f810238
Add missing entries and fix rST formatting in whats-new
dcherian Jan 28, 2026
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
4 changes: 1 addition & 3 deletions HOW_TO_RELEASE.md
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -28,11 +28,9 @@ upstream https://github.com/pydata/xarray (push)
Then run

```sh
python ci/release_contributors.py
pixi run release-contributors
```

(needs `gitpython` and `toolz` / `cytoolz`)

and copy the output.

3. Write a release summary: ~50 words describing the high level features. This
Expand Down
66 changes: 45 additions & 21 deletions doc/whats-new.rst
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -6,10 +6,14 @@
What's New
==========

.. _whats-new.v2025.12.1:
.. _whats-new.2026.01.0:

v2025.12.1 (unreleased)
-----------------------
v2026.01.0 (Jan 28, 2026)
-------------------------
This release includes an improved DataTree HTML representation with collapsible groups and automatic truncation, easier selection on coordinates without explicit indexes, pandas 3 compatibility, and various bug fixes and performance improvements.

Thanks to the 25 contributors to this release:
Barron H. Henderson, Christine P. Chai, DHRUVA KUMAR KAUSHAL, David Bold, Davis Bennett, Deepak Cherian, Dhruva Kumar Kaushal, Florian Knappers, Ian Hunt-Isaak, Jacob Tomlinson, Joshua Gould, Julia Signell, Justus Magin, Lucas Colley, Mark Harfouche, Matthew, Maximilian Roos, Nick Hodgskin, Sakshee_D, Sam Levang, Samay Mehar, Simon Høxbro Hansen, Spencer Clark, Stephan Hoyer and knappersfy

New Features
~~~~~~~~~~~~
Expand All @@ -34,37 +38,33 @@ New Features
<https://github.com/hmaarrfk>`_.
- :py:func:`set_options` now supports an ``arithmetic_compat`` option which determines how non-index coordinates
of the same name are compared for potential conflicts when performing binary operations. The default for it is
``arithmetic_compat='minimal'`` which matches the existing behaviour.
``arithmetic_compat='minimal'`` which matches the existing behaviour (:pull:`10943`).
By `Matthew Willson <https://github.com/mjwillson>`_.
- Better ordering of coordinates when displaying Xarray objects. (:pull:`11098`).
- Better ordering of coordinates when displaying xarray objects (:pull:`11091`).
By `Ian Hunt-Isaak <https://github.com/ianhi>`_, `Julia Signell <https://github.com/jsignell>`_.
- Use ``np.dtypes.StringDType`` when reading Zarr string variables (:pull:`11097`).
By `Julia Signell <https://github.com/jsignell>`_.

Breaking Changes
~~~~~~~~~~~~~~~~

- Change the default value for ``chunk`` in ``open_zarr`` to ``_default`` and remove special mapping of ``"auto"``
to ``{}`` or ``None`` in ``open_zarr``. If ``chunks`` is not set, the default behavior is the same as before.
- Change the default value for ``chunk`` in :py:func:`open_zarr` to ``_default`` and remove special mapping of ``"auto"``
to ``{}`` or ``None`` in :py:func:`open_zarr`. If ``chunks`` is not set, the default behavior is the same as before.
Explicitly setting ``chunks="auto"`` will match the behavior of ``chunks="auto"`` in
``open_dataset(..., engine="zarr")`` (:issue:`11002` :pull:`11010`).
:py:func:`open_dataset` with ``engine="zarr"`` (:issue:`11002`, :pull:`11010`).
By `Julia Signell <https://github.com/jsignell>`_.
- :py:meth:`Dataset.identical`,` :py:meth:`DataArray.identical`, and
:py:func:`testings.assert_identical` now compare indexes (xindexes).
- :py:meth:`Dataset.identical`, :py:meth:`DataArray.identical`, and
:py:func:`testing.assert_identical` now compare indexes.
Two objects with identical data but different indexes will no longer
be considered identical. This also affects (:issue:`11033` :pull:`11035`).
be considered identical (:issue:`11033`, :pull:`11035`).
By `Ian Hunt-Isaak <https://github.com/ianhi>`_.


Deprecations
~~~~~~~~~~~~


Bug Fixes
~~~~~~~~~

- Ensure that ``keep_attrs='drop'`` and ``keep_attrs=False`` remove attrs from result, even when there is
only one xarray object given to ``apply_ufunc`` (:issue:`10982` :pull:`10997`).
only one xarray object given to :py:func:`apply_ufunc` (:issue:`10982`, :pull:`10997`).
By `Julia Signell <https://github.com/jsignell>`_.
- :py:meth:`~xarray.indexes.RangeIndex.equals` now uses floating point error tolerant
``np.isclose`` by default to handle accumulated floating point errors from
Expand All @@ -76,23 +76,47 @@ Bug Fixes
- Partially support pandas 3 default string indexes by coercing ``pd.StringDtype``
to ``np.dtypes.StringDType`` in ``PandasIndexingAdapter`` (:issue:`11098`, :pull:`11102`).
By `Julia Signell <https://github.com/jsignell>`_.
- :py:meth:`Dataset.eval` now works with more than 2 dimensions (:pull:`11064`).
By `Maximilian Roos <https://github.com/max-sixty>`_.
- Fix :py:func:`where` for ``cupy.array`` inputs (:pull:`11026`).
By `Simon Høxbro Hansen <https://github.com/hoxbro>`_.
- Fix :py:meth:`CombinedLock.locked` to correctly call the underlying lock's
``locked()`` method (:issue:`10843`, :pull:`11022`).
By `Samay Mehar <https://github.com/samay2504>`_.
- Fix :py:meth:`DatasetGroupBy.map` when grouping by more than one variable (:pull:`11005`).
By `Joshua Gould <https://github.com/joshua-gould>`_.
- Fix indexing bugs in :py:class:`~xarray.indexes.CoordinateTransformIndex` (:pull:`10980`).
By `Deepak Cherian <https://github.com/dcherian>`_.
- Ensure the netCDF4 backend locks files while closing to prevent race conditions (:pull:`10788`).
By `David Bold <https://github.com/dschwoerer>`_.
- Improve error message when scipy is missing for :py:class:`~xarray.indexes.NDPointIndex` (:pull:`11085`).
By `Sakshee_D <https://github.com/Sakshee-D>`_.

Documentation
~~~~~~~~~~~~~

- Better description of ``keep_attrs`` option on ``xarray.where`` docstring (:issue:`10982` :pull:`10997`).
- Better description of ``keep_attrs`` option on :py:func:`xarray.where` docstring (:issue:`10982`, :pull:`10997`).
By `Julia Signell <https://github.com/jsignell>`_.
- Document how :py:func:`xarray.dot` interacts with coordinates (:pull:`10958`).
By `Dhruva Kumar Kaushal <https://github.com/dhruvak001>`_.
- Improve ``rolling`` window documentation (:pull:`11094`).
By `Barron H. Henderson <https://github.com/barronh>`_.
- Improve ``combine_nested`` and ``combine_by_coords`` docstrings (:pull:`11080`).
By `Julia Signell <https://github.com/jsignell>`_.

Internal Changes
~~~~~~~~~~~~~~~~


Performance
~~~~~~~~~~~

- Add a fastpath to the backend plugin system for standard engines (:issue:`10178`, :pull:`10937`).
By `Sam Levang <https://github.com/slevang>`_.
- Optimize :py:class:`~xarray.coding.variables.CFMaskCoder` decoder (:pull:`11105`).
By `Deepak Cherian <https://github.com/dcherian>`_.

Internal Changes
~~~~~~~~~~~~~~~~

- Update contributing instructions with note on pixi version (:pull:`11108`).
By `Nick Hodgskin <https://github.com/VeckoTheGecko>`_.

.. _whats-new.2025.12.0:

Expand Down
Loading