dev(matmul): add support for matmul operator

grassmann_tensor/tensor.py

@@ -756,6 +756,19 @@ def __itruediv__(self, other: typing.Any) -> GrassmannTensor:
             return self
         return NotImplemented
 
+    def __matmul__(self, other: typing.Any) -> GrassmannTensor:
+        if isinstance(other, GrassmannTensor):
+            return self.matmul(other)
+        return NotImplemented
+
+    def __rmatmul__(self, other: typing.Any) -> GrassmannTensor:
+        return NotImplemented
+
+    def __imatmul__(self, other: typing.Any) -> GrassmannTensor:
+        if isinstance(other, GrassmannTensor):
+            return self.matmul(other)
+        return NotImplemented
+
     def clone(self) -> GrassmannTensor:
         """
         Create a deep copy of the Grassmann tensor.

tests/matmul_test.py

@@ -1,17 +1,29 @@
 import pytest
 import torch
+import typing
 from grassmann_tensor import GrassmannTensor
 
 Broadcast = tuple[tuple[int, ...], tuple[int, ...], tuple[int, ...]]
 MatmulCase = tuple[bool, bool, tuple[int, int], tuple[int, int], tuple[int, int]]
 
 
-@pytest.mark.parametrize("a_is_vector", [False, True])
-@pytest.mark.parametrize("b_is_vector", [False, True])
-@pytest.mark.parametrize("normal_arrow_order", [False, True])
-@pytest.mark.parametrize(
-    "broadcast",
-    [
+@pytest.fixture(params=[False, True])
+def a_is_vector(request: pytest.FixtureRequest) -> bool:
+    return request.param
+
+
+@pytest.fixture(params=[False, True])
+def b_is_vector(request: pytest.FixtureRequest) -> bool:
+    return request.param
+
+
+@pytest.fixture(params=[False, True])
+def normal_arrow_order(request: pytest.FixtureRequest) -> bool:
+    return request.param
+
+
+@pytest.fixture(
+    params=[
         ((), (), ()),
         ((2,), (), (2,)),
         ((), (3,), (3,)),
@@ -27,9 +39,12 @@
         ((7, 8), (7, 1), (7, 8)),
     ],
 )
-@pytest.mark.parametrize(
-    "x",
-    [
+def broadcast(request: pytest.FixtureRequest) -> Broadcast:
+    return request.param
+
+
+@pytest.fixture(
+    params=[
         (False, False, (1, 1), (1, 1), (1, 1)),
         (False, True, (1, 1), (1, 1), (1, 1)),
         (True, False, (1, 1), (1, 1), (1, 1)),
@@ -40,6 +55,10 @@
         (True, True, (2, 2), (2, 2), (2, 2)),
     ],
 )
+def x(request: pytest.FixtureRequest) -> MatmulCase:
+    return request.param
+
+
 def test_matmul(
     a_is_vector: bool,
     b_is_vector: bool,
@@ -101,40 +120,6 @@ def test_matmul(
     assert torch.allclose(c.tensor, expected)
 
 
-@pytest.mark.parametrize("a_is_vector", [False, True])
-@pytest.mark.parametrize("b_is_vector", [False, True])
-@pytest.mark.parametrize("normal_arrow_order", [False, True])
-@pytest.mark.parametrize(
-    "broadcast",
-    [
-        ((), (), ()),
-        ((2,), (), (2,)),
-        ((), (3,), (3,)),
-        ((1,), (4,), (4,)),
-        ((5,), (1,), (5,)),
-        ((6,), (6,), (6,)),
-        ((7, 8), (7, 8), (7, 8)),
-        ((1, 8), (7, 8), (7, 8)),
-        ((8,), (7, 8), (7, 8)),
-        ((7, 1), (7, 8), (7, 8)),
-        ((7, 8), (1, 8), (7, 8)),
-        ((7, 8), (8,), (7, 8)),
-        ((7, 8), (7, 1), (7, 8)),
-    ],
-)
-@pytest.mark.parametrize(
-    "x",
-    [
-        (False, False, (1, 1), (1, 1), (1, 1)),
-        (False, True, (1, 1), (1, 1), (1, 1)),
-        (True, False, (1, 1), (1, 1), (1, 1)),
-        (True, True, (1, 1), (1, 1), (1, 1)),
-        (False, False, (2, 2), (2, 2), (2, 2)),
-        (False, True, (2, 2), (2, 2), (2, 2)),
-        (True, False, (2, 2), (2, 2), (2, 2)),
-        (True, True, (2, 2), (2, 2), (2, 2)),
-    ],
-)
 @pytest.mark.parametrize("impure_even_for_broadcast_indices", [1, 2])
 def test_matmul_unpure_even(
     a_is_vector: bool,
@@ -191,3 +176,99 @@ def test_matmul_unpure_even(
         pytest.skip("One of the two tensors needs to have a dimension greater than 2")
     with pytest.raises(AssertionError, match="All edges except the last two must be pure even"):
         _ = a.matmul(b)
+
+
+def test_matmul_operator_matmul(
+    a_is_vector: bool,
+    b_is_vector: bool,
+    normal_arrow_order: bool,
+    broadcast: Broadcast,
+) -> None:
+    normal_arrow_order = True
+    broadcast_a, broadcast_b, broadcast_result = (7, 8), (7, 1), (7, 8)
+    arrow_a, arrow_b, edge_a, edge_common, edge_b = True, True, (2, 2), (2, 2), (2, 2)
+    dim_a = sum(edge_a)
+    dim_common = sum(edge_common)
+    dim_b = sum(edge_b)
+    a = GrassmannTensor(
+        (*(False for _ in broadcast_a), arrow_a, True if normal_arrow_order else False),
+        (*((i, 0) for i in broadcast_a), edge_a, edge_common),
+        torch.randn([*broadcast_a, dim_a, dim_common]),
+    ).update_mask()
+
+    b = GrassmannTensor(
+        (*(False for _ in broadcast_b), False if normal_arrow_order else True, arrow_b),
+        (*((i, 0) for i in broadcast_b), edge_common, edge_b),
+        torch.randn([*broadcast_b, dim_common, dim_b]),
+    ).update_mask()
+
+    c = a @ b
+    expected = a.tensor.matmul(b.tensor)
+    assert c.arrow == (*(False for _ in broadcast_result), arrow_a, arrow_b)
+    assert c.edges == (*((i, 0) for i in broadcast_result), edge_a, edge_b)
+    assert torch.allclose(c.tensor, expected)
+
+
+@pytest.fixture(
+    params=[
+        GrassmannTensor((False, False), ((2, 2), (1, 3)), torch.randn([4, 4])),
+        GrassmannTensor((True, False, True), ((1, 1), (2, 2), (3, 1)), torch.randn([2, 4, 4])),
+        GrassmannTensor(
+            (True, True, False, False), ((1, 2), (2, 2), (1, 1), (3, 1)), torch.randn([3, 4, 2, 4])
+        ),
+    ]
+)
+def tensors(request: pytest.FixtureRequest) -> GrassmannTensor:
+    return request.param
+
+
+@pytest.mark.parametrize(
+    "unsupported_type",
+    [
+        "string",  # string
+        None,  # NoneType
+        {"key", "value"},  # dict
+        [1, 2, 3],  # list
+        {1, 2},  # set
+        object(),  # arbitrary object
+    ],
+)
+def test_matmul_unsupported_type_raises_typeerror(
+    unsupported_type: typing.Any,
+    tensors: GrassmannTensor,
+) -> None:
+    with pytest.raises(TypeError):
+        _ = tensors @ unsupported_type
+
+    with pytest.raises(TypeError):
+        _ = unsupported_type @ tensors
+
+    with pytest.raises(TypeError):
+        tensors @= unsupported_type
+
+
+def test_matmul_operator_rmatmul() -> None:
+    normal_arrow_order = True
+    broadcast_a, broadcast_b, broadcast_result = (7, 8), (7, 1), (7, 8)
+    arrow_a, arrow_b, edge_a, edge_common, edge_b = True, True, (2, 2), (2, 2), (2, 2)
+    dim_a = sum(edge_a)
+    dim_common = sum(edge_common)
+    dim_b = sum(edge_b)
+    a = GrassmannTensor(
+        (*(False for _ in broadcast_a), arrow_a, True if normal_arrow_order else False),
+        (*((i, 0) for i in broadcast_a), edge_a, edge_common),
+        torch.randn([*broadcast_a, dim_a, dim_common]),
+    ).update_mask()
+
+    b = GrassmannTensor(
+        (*(False for _ in broadcast_b), False if normal_arrow_order else True, arrow_b),
+        (*((i, 0) for i in broadcast_b), edge_common, edge_b),
+        torch.randn([*broadcast_b, dim_common, dim_b]),
+    ).update_mask()
+
+    c = a
+    c @= b
+    expected = a.tensor.matmul(b.tensor)
+    assert c.arrow == (*(False for _ in broadcast_result), arrow_a, arrow_b)
+    assert c.edges == (*((i, 0) for i in broadcast_result), edge_a, edge_b)
+    assert torch.allclose(c.tensor, expected)