TST: matmul does not conjugate; wrong?

mhvk · mhvk · commit 09d4504b1cc3 · 2024-01-30T10:12:13.000-05:00
diff --git a/numpy/_core/code_generators/ufunc_docstrings.py b/numpy/_core/code_generators/ufunc_docstrings.py
@@ -2965,12 +2965,12 @@ def add_newdoc(place, name, doc):
     Rotate a set of vectors from Y to X along Z.
 
     >>> a = np.array([[0., 1., 0.], [-1., 0., 0.], [0., 0., 1.]])
-    >>> v = np.array([[1., 0., 0.], [0., 1., 0.], [0., 0., 1.], [0., 0.6, 0.8]])
+    >>> v = np.array([[1., 0., 0.], [0., 1., 0.], [0., 0., 1.], [0., 6., 8.]])
     >>> np.matvec(a, v)
-    array([[ 0. , -1. ,  0. ],
-           [ 1. ,  0. ,  0. ],
-           [ 0. ,  0. ,  1. ],
-           [ 0.6,  0. ,  0.8]])
+    array([[ 0., -1.,  0.],
+           [ 1.,  0.,  0.],
+           [ 0.,  0.,  1.],
+           [ 6.,  0.,  8.]])
 
     .. versionadded:: 2.0.0
     """)
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(),
