Generate reductions for DataArray, Dataset, GroupBy and Resample (#5950)

Co-authored-by: Illviljan <14371165+Illviljan@users.noreply.github.com>
Co-authored-by: Mathias Hauser <mathause@users.noreply.github.com>
Co-authored-by: Stephan Hoyer <shoyer@google.com>
Co-authored-by: pre-commit-ci[bot] <66853113+pre-commit-ci[bot]@users.noreply.github.com>

Author: 5 people

doc/user-guide/computation.rst

@@ -107,6 +107,8 @@ Xarray also provides the ``max_gap`` keyword argument to limit the interpolation
 data gaps of length ``max_gap`` or smaller. See :py:meth:`~xarray.DataArray.interpolate_na`
 for more.
 
+.. _agg:
+
 Aggregation
 ===========