array_function

pint_pandas/pint_array.py

@@ -327,6 +327,11 @@ def __setstate__(self, dct):
         self.__dict__.update(dct)
         self._Q = self.dtype.ureg.Quantity
 
+    def __array_function__(self, func, types, args, kwargs):
+        args = convert_np_inputs(args)
+        result = func(*args, **kwargs)
+        return self._convert_np_result(result)
+
     def __array_ufunc__(self, ufunc, method, *inputs, **kwargs):
         out = kwargs.get("out", ())
         for x in inputs + out:

pint_pandas/testsuite/test_issues.py

@@ -311,3 +311,16 @@ def test_issue246(self):
 
         # now an operation where each cell is independent from each other
         df.apply(lambda x: x * 2, axis=1)
+
+
+class TestIssue255(BaseExtensionTests):
+    def test_issue255(self):
+        a = np.r_[1, 2, np.nan, 4, 10]
+        pa = PintArray.from_1darray_quantity(a * ureg.m)
+
+        result = np.clip(pa, 3 * ureg.m, 5 * ureg.m)
+
+        e = np.clip(a, 3, 5)
+        expected = PintArray.from_1darray_quantity(e * ureg.m)
+
+        tm.assert_equal(result, expected)