TST: matmul does not conjugate; wrong?

mhvk · mhvk · commit a7ac2119788f · 2024-01-23T17:11:14.000-05:00
diff --git a/numpy/_core/tests/test_ufunc.py b/numpy/_core/tests/test_ufunc.py
@@ -868,6 +868,10 @@ def test_vecdot_matvec_vecmat_complex(self, ufunc, shape1, shape2, conj):
         expected1 = np.array(((arr1.conj() if conj else arr1) * arr2).sum(),
                              ndmin=min(len(shape1), len(shape2)))
         assert_array_equal(actual1, expected1)
+        # This would fail for conj=True, since matmul omits the conjugate.
+        if not conj:
+            assert_array_equal(arr1.reshape(shape1) @ arr2.reshape(shape2),
+                               expected1)
 
         actual2 = ufunc(arr2.reshape(shape1), arr1.reshape(shape2))
         expected2 = np.array(((arr2.conj() if conj else arr2) * arr1).sum(),
