Doc changes in whats-new.rst & cleaned up testing import permutation.

Author: shazelquist

doc/whats-new.rst

@@ -23,6 +23,8 @@ v0.19.1 (unreleased)
 
 New Features
 ~~~~~~~~~~~~
+- Added an optional ``tolerance`` argument to :py:func:`isin` for numerically close datasets (:issue:`5587`, :pull:`5862`).
+  By `Shane Hazelquist <https://github.com/shazelquist>`.
 - Added a :py:func:`get_options` method to xarray's root namespace (:issue:`5698`, :pull:`5716`)
   By `Pushkar Kopparla <https://github.com/pkopparla>`_.
 - Xarray now does a better job rendering variable names that are long LaTeX sequences when plotting (:issue:`5681`, :pull:`5682`).

xarray/tests/test_duck_array_ops.py

@@ -7,7 +7,7 @@
 import pytest
 from numpy import array, nan
 
-from xarray import DataArray, Dataset, cftime_range, concat
+from xarray import DataArray, Dataset, cftime_range, concat, testing
 from xarray.core import dtypes, duck_array_ops
 from xarray.core.duck_array_ops import (
     array_notnull_equiv,
@@ -902,7 +902,6 @@ def test_push_dask():
 def test_isin_tolerance(shape, tolerance, dask_for_A, dask_for_B):
     if (dask_for_A or dask_for_B) and not has_dask:
         pytest.skip("requires dask")
-    from xarray.testing import assert_duckarray_equal
 
     in_margin = tolerance / 2  # measure within acceptable margin
     arrayA = np.arange(-10.0, 10.0, 0.1).reshape(shape)
@@ -926,7 +925,7 @@ def test_isin_tolerance(shape, tolerance, dask_for_A, dask_for_B):
             # test function
             actual = isin_tolerance(arrayA, arrayB, tolerance)
 
-            assert_duckarray_equal(actual, expected)
+            testing.assert_duckarray_equal(actual, expected)
             if dask_for_A:
                 assert isinstance(actual, dask_array_type)
             else:
@@ -938,5 +937,5 @@ def test_isin_tolerance(shape, tolerance, dask_for_A, dask_for_B):
             # test function
             actual = isin_tolerance(arrayA, arrayB, tolerance)
 
-            assert_duckarray_equal(actual, expected)
+            testing.assert_duckarray_equal(actual, expected)
             assert isinstance(actual, np.ndarray)