What’s new

0.6.2 (23-11-2021)

Bug fixes

  • The introduction of sparse, with numba under the hood, restricted input data to little-endian dtypes. For big-endian dtypes, xESMF will convert to little-endian, regrid and convert back (PR135). By Pascal Bourgault
  • SpatialAverager did not compute the same weights as Regridder when source cell areas were not uniform (PR128). By David Huard
  • Refactor of how the regridding is called internally, to fix a bug with dask and sparse (PR135). By Pascal Bourgault

Internal changes

  • Deprecation of regrid_numpy and regrid_dask is scheduled for 0.7.0. All checks on shape, array layout and numba support are now done at call time, rather then at computation time (PR135).

0.6.1 (23-09-2021)

Note that this version creates very large dask task graphs that can affect performance for large grids.

Internal changes

  • Weights are now stored in a xr.DataArray backed by sparse.COO, which allows to pass them as an argument to the xr.apply_ufunc and decrease memory usage when using dask. By Pascal Bourgault
  • New dependency sparse replacing scipy.

0.6.0 (07-08-2021)

New features

  • Add the skipna and na_threshold options to deal with masks over non-spatial dimensions (PR29). This is useful when, for example, masks vary over time. By Stéphane Raynaud
  • Add unmapped_to_nan argument to regridder frontend. When True, this sets target cells outside the source domain to NaN instead of zero for all regridding methods except nearest neighbour (PR94). By Martin Schupfner

Bug fixes

  • Drop the PyPi badge and replace by a Conda badge (PR97). By Ray Bell

0.5.3 (04-12-2021)

Bug fixes

Documentation

0.5.2 (01-20-2021)

Bug fixes

  • Restore original behavior for lon/lat discovery, uses cf-xarray if lon/lat not found in dataset (PR64)
  • Solve issue of dimension order in dataset (#53) with (PR66)

0.5.1 (01-11-2021)

Documentation

  • Update installation instructions to mention that PyPi only holds xesmf up to version 0.3.0.

New features

  • Regridded xarray.Dataset now preserves the name and attributes of target coordinates (PR60)

Bug fixes

  • Fix doc build for API/Regridder (PR61)

0.5.0 (11-11-2020)

Breaking changes

  • Deprecate esmf_grid in favor of Grid.from_xarray
  • Deprecate esmf_locstream in favor of LocStream.from_xarray
  • Installation requires numpy>=1.16 and cf-xarray>=0.3.1

New features

  • Create ESMF.Mesh objects from shapely.polygons (PR24). By Pascal Bourgault
  • New class SpatialAverager offers user-friendly mechanism to average a 2-D field over a polygon. Includes support to handle interior holes and multi-part geometries. (PR24) By Pascal Bourgault
  • Automatic detection of coordinates and computation of vertices based on cf-xarray. (PR49) By Pascal Bourgault

Bug fixes

Internal changes

  • Subclass ESMF.Mesh and create from_polygon method
  • Subclass ESMF.Grid and ESMF.LocStream and create from_xarray methods.
  • New BaseRegridder class, with support for Grid, LocStream and Mesh objects. Not all regridding methods are supported for Mesh objects.
  • Refactor Regridder to subclass BaseRegridder.

0.4.0 (01-10-2020)

The git repo is now hosted by pangeo-data (https://github.com/pangeo-data/xESMF)

Breaking changes

  • By default, weights are not written to disk, but instead kept in memory.
  • Installation requires ESMPy 8.0.0 and up.

New features

  • The Regridder object now takes a weights argument accepting a scipy.sparse COO matrix, a dictionary, an xarray.Dataset, or a path to a netCDF file created by ESMF. If None, weights are computed and can be written to disk using the to_netcdf method. This weights parameter replaces the filename and reuse_weights arguments, which are preserved for backward compatibility (PR3). By David Huard and Raphael Dussin
  • Added documentation discussion how to compute weights from a shell using MPI, and reuse from xESMF (PR12). By Raphael Dussin
  • Add support for masks in :py:func`esmf_grid`. This avoid NaNs to bleed into the interpolated values. When using a mask and the conservative regridding method, use a new method called conservative_normed to properly handle normalization (PR1). By Raphael Dussin

0.3.0 (06-03-2020)

New features

0.2.2 (07-10-2019)

New features

0.2.0 (04-08-2019)

Breaking changes

All user-facing APIs in v0.1.x should still work exactly the same. That said, because some internal codes have changed a lot, there might be unexpected edge cases that break current user code. If that happens, you can revert to the previous version by pip install xesmf==0.1.2 and follow old docs.

New features

  • Lazy evaluation on dask arrays (uses xarray.apply_ufunc() and dask.array.map_blocks())
  • Automatic looping over variables in an xarray Dataset
  • Add tutorial notebooks on those new features

By Jiawei Zhuang

0.1.2 (03-08-2019)

This release mostly contains internal clean-ups to facilitate future development.

New features

  • Deprecates regridder.A in favor of regridder.weights
  • Speed-up test suites by using coarser grids
  • Use parameterized tests when appropriate
  • Fix small memory leaks from ESMF.Grid
  • Properly assert ESMF enums

By Jiawei Zhuang

0.1.1 (31-12-2017)

Initial release. By Jiawei Zhuang