v0.20.2

This is a bugfix release to resolve xr.corr & xr.map_blocks when dask is not installed.
It also includes performance improvements in unstacking to a sparse array and a
number of documentation improvements.

Many thanks to the 20 contributors:

Aaron Spring, Alexandre Poux, Deepak Cherian, Enrico Minack, Fabien Maussion,
Giacomo Caria, Gijom, Guillaume Maze, Illviljan, Joe Hamman, Joseph Hardin, Kai
Mühlbauer, Matt Henderson, Maximilian Roos, Michael Delgado, Robert Gieseke,
Sebastian Weigand and Stephan Hoyer.

v0.20.1

This is a bugfix release for a major bug in v0.20.0

v0.20.0

This release brings improved support for pint arrays, methods for weighted standard deviation, variance, and sum of squares, the option to disable the use of the bottleneck library, significantly improved performance of unstack, as well as many bugfixes and internal changes.

v0.19.0

This release brings improvements to plotting of categorical data, the ability to specify how attributes are combined in xarray operations, a new high-level unify_chunks function, as well as various deprecations, bug fixes, and minor improvements.

v0.18.2

This release reverts a regression in xarray's unstacking of dask-backed arrays.

v0.18.1

This release is intended as a small patch release to be compatible with the new 2021.5.0 dask.distributed release. It also includes a new drop_duplicates method, some documentation improvements, the beginnings of our internal Index refactoring, and some bug fixes.

v0.18.0

This release brings a few important performance improvements, a wide range of usability upgrades, lots of bug fixes, and some new features. These include a plugin API to add backend engines, a new theme for the documentation, curve fitting methods, and several new plotting functions.

v0.17.0

This release brings a few important performance improvements, a wide range of usability upgrades, lots of bug fixes, and some new features. These include better cftime support, a new quiver plot, better unstack performance, more efficient memory use in rolling operations, and some python packaging improvements. We also have a few documentation improvements (and more planned!).

v0.16.2

This release brings the ability to write to limited regions of zarr files, open zarr files with open_dataset and open_mfdataset, increased support for propagating attrs using the keep_attrs flag, as well as numerous bugfixes and documentation improvements.

v0.16.1

This patch release fixes an incompatibility with a recent pandas change, which was causing an issue indexing with a datetime64. It also includes improvements to rolling, to_dataframe, cov & corr methods and bug fixes. Our documentation has a number of improvements, including fixing all doctests and confirming their accuracy on every commit.