Pass kwargs and assume_sorted to xarray interp for both DataArray and Dataset (#270)

* pass kwargs and assume_sorted to xarray interp for both DataArray and Dataset

* update docstring, whats-new and adapt interp test to test for kwarg passing

* Explicit dict for quantify

Co-authored-by: Justus Magin <[email protected]>

* move kwargs test to separate parameter set

---------

Co-authored-by: Justus Magin <[email protected]>

Author: martijnvandermarel

docs/whats-new.rst

@@ -8,6 +8,9 @@ What's new
   By `Justus Magin <https://github.com/keewis>`_.
 - create a `PintIndex` to allow units on indexed coordinates (:pull:`163`, :issue:`162`)
   By `Justus Magin <https://github.com/keewis>`_ and `Benoit Bovy <https://github.com/benbovy>`_.
+- fix :py:meth:`Dataset.pint.interp` and :py:meth:`DataArray.pint.interp` bug
+  failing to pass through arguments (:pull:`270`, :issue:`267`)
+  By `Martijn van der Marel <https://github.com/martijnvandermarel>`_
 
 0.4 (23 Jun 2024)
 -----------------

pint_xarray/accessors.py

@@ -716,7 +716,8 @@ def interp(
         converted to the units of the indexers first.
 
         .. note::
-            ``kwargs`` is passed unmodified to ``DataArray.interp``
+            ``method``, ``assume_sorted`` and ``kwargs`` are passed unmodified to
+            ``DataArray.interp``.
 
         See Also
         --------
@@ -742,8 +743,8 @@ def interp(
         interpolated = stripped.interp(
             stripped_indexers,
             method=method,
-            assume_sorted=False,
-            kwargs=None,
+            assume_sorted=assume_sorted,
+            kwargs=kwargs,
         )
         return conversion.attach_units(interpolated, units)
 
@@ -754,7 +755,8 @@ def interp_like(self, other, method="linear", assume_sorted=False, kwargs=None):
         to the units of the indexers first.
 
         .. note::
-            ``kwargs`` is passed unmodified to ``DataArray.interp``
+            ``method``, ``assume_sorted`` and ``kwargs`` are passed unmodified to
+            ``DataArray.interp``.
 
         See Also
         --------
@@ -1483,7 +1485,8 @@ def interp(
         to the units of the indexers first.
 
         .. note::
-            ``kwargs`` is passed unmodified to ``Dataset.interp``
+            ``method``, ``assume_sorted`` and ``kwargs`` are passed unmodified to
+            ``DataArray.interp``.
 
         See Also
         --------
@@ -1509,8 +1512,8 @@ def interp(
         interpolated = stripped.interp(
             stripped_indexers,
             method=method,
-            assume_sorted=False,
-            kwargs=None,
+            assume_sorted=assume_sorted,
+            kwargs=kwargs,
         )
         return conversion.attach_units(interpolated, units)
 
@@ -1521,7 +1524,8 @@ def interp_like(self, other, method="linear", assume_sorted=False, kwargs=None):
         converted to the units of the indexers first.
 
         .. note::
-            ``kwargs`` is passed unmodified to ``Dataset.interp``
+            ``method``, ``assume_sorted`` and ``kwargs`` are passed unmodified to
+            ``DataArray.interp``.
 
         See Also
         --------

pint_xarray/tests/test_accessors.py

@@ -1437,7 +1437,7 @@ def test_reindex_like(obj, units, other, other_units, expected, expected_units,
 
 @requires_scipy
 @pytest.mark.parametrize(
-    ["obj", "units", "indexers", "expected", "expected_units", "error"],
+    ["obj", "units", "indexers", "expected", "expected_units", "error", "kwargs"],
     (
         pytest.param(
             xr.Dataset({"x": ("x", [10, 20, 30]), "y": ("y", [60, 120])}),
@@ -1446,6 +1446,7 @@ def test_reindex_like(obj, units, other, other_units, expected, expected_units,
             xr.Dataset({"x": ("x", [10, 30, 50]), "y": ("y", [0, 120, 240])}),
             {"x": "dm", "y": "s"},
             None,
+            None,
             id="Dataset-identical units",
         ),
         pytest.param(
@@ -1455,6 +1456,7 @@ def test_reindex_like(obj, units, other, other_units, expected, expected_units,
             xr.Dataset({"x": ("x", [0, 1, 3, 5]), "y": ("y", [0, 2, 4])}),
             {"x": "m", "y": "min"},
             None,
+            None,
             id="Dataset-compatible units",
         ),
         pytest.param(
@@ -1464,6 +1466,7 @@ def test_reindex_like(obj, units, other, other_units, expected, expected_units,
             None,
             {},
             ValueError,
+            None,
             id="Dataset-incompatible units",
         ),
         pytest.param(
@@ -1488,6 +1491,7 @@ def test_reindex_like(obj, units, other, other_units, expected, expected_units,
             ),
             {"a": "kg"},
             None,
+            None,
             id="Dataset-data units",
         ),
         pytest.param(
@@ -1505,6 +1509,7 @@ def test_reindex_like(obj, units, other, other_units, expected, expected_units,
             ),
             {"x": "dm", "y": "s"},
             None,
+            None,
             id="DataArray-identical units",
         ),
         pytest.param(
@@ -1522,6 +1527,7 @@ def test_reindex_like(obj, units, other, other_units, expected, expected_units,
             ),
             {"x": "m", "y": "min"},
             None,
+            None,
             id="DataArray-compatible units",
         ),
         pytest.param(
@@ -1535,6 +1541,7 @@ def test_reindex_like(obj, units, other, other_units, expected, expected_units,
             None,
             {},
             ValueError,
+            None,
             id="DataArray-incompatible units",
         ),
         pytest.param(
@@ -1552,20 +1559,39 @@ def test_reindex_like(obj, units, other, other_units, expected, expected_units,
             ),
             {None: "kg"},
             None,
+            None,
             id="DataArray-data units",
         ),
+        pytest.param(
+            xr.DataArray(
+                [[0, 1], [2, 3], [4, 5]],
+                dims=("x", "y"),
+                coords={"x": ("x", [10, 20, 30]), "y": ("y", [60, 120])},
+            ),
+            {"x": "dm", "y": "s"},
+            {"x": Quantity([1, 3, 5], "m"), "y": Quantity([0, 2], "min")},
+            xr.DataArray(
+                [[0, 1], [0, 5], [0, 0]],
+                dims=("x", "y"),
+                coords={"x": ("x", [1, 3, 5]), "y": ("y", [0, 2])},
+            ),
+            {"x": "m", "y": "min"},
+            None,
+            {"bounds_error": False, "fill_value": 0},
+            id="DataArray-other parameters",
+        ),
     ),
 )
-def test_interp(obj, units, indexers, expected, expected_units, error):
+def test_interp(obj, units, indexers, expected, expected_units, error, kwargs):
     obj_ = obj.pint.quantify(units)
 
     if error is not None:
         with pytest.raises(error):
-            obj.pint.interp(indexers)
+            obj_.pint.interp(indexers, kwargs=kwargs)
     else:
         expected_ = expected.pint.quantify(expected_units)
 
-        actual = obj_.pint.interp(indexers)
+        actual = obj_.pint.interp(indexers, kwargs=kwargs)
         assert_units_equal(actual, expected_)
         assert_identical(actual, expected_)