# Copyright © 2023-2024 Apple Inc. import gc import unittest import mlx.core as mx import mlx_tests class TestVmap(mlx_tests.MLXTestCase): def test_basics(self): # Can't vmap over scalars with self.assertRaises(ValueError): mx.vmap(mx.exp)(mx.array(1.0)) # Invalid input with self.assertRaises(ValueError): mx.vmap(mx.exp)("hello") # Invalid axes with self.assertRaises(ValueError): mx.vmap(mx.exp, in_axes="hello")(mx.array([0, 1])) with self.assertRaises(ValueError): mx.vmap(mx.exp, in_axes=2)(mx.array([0, 1])) with self.assertRaises(ValueError): mx.vmap(mx.exp, out_axes="hello")(mx.array([0, 1])) with self.assertRaises(ValueError): mx.vmap(mx.exp, out_axes=2)(mx.array([0, 1])) def test_unary(self): ops = [ "abs", "cos", "erf", "erfinv", "exp", "log", "log1p", "log2", "log10", "logical_not", "negative", "reciprocal", "rsqrt", "sigmoid", "sign", "sin", "sqrt", "square", "degrees", "radians", ] for opname in ops: with self.subTest(op=opname): op = getattr(mx, opname) x = mx.arange(5) y = mx.vmap(op)(x) self.assertTrue(mx.array_equal(y, op(x), equal_nan=True)) x = mx.arange(8).reshape(2, 4) y = mx.vmap(op)(x) self.assertTrue(mx.array_equal(y, op(x), equal_nan=True)) y = mx.vmap(op, in_axes=1, out_axes=1)(x) self.assertTrue(mx.array_equal(y, op(x), equal_nan=True)) def test_binary(self): ops = [ "add", "divide", "equal", "greater", "greater_equal", "less", "less_equal", "logaddexp", "maximum", "minimum", "multiply", "power", "subtract", "logical_or", "logical_and", ] for opname in ops: with self.subTest(op=opname): op = getattr(mx, opname) x = mx.random.uniform(shape=(5,)) y = mx.random.uniform(shape=(5,)) out = mx.vmap(op)(x, y) self.assertTrue(mx.array_equal(out, op(x, y))) x = mx.random.uniform(shape=(2, 4)) y = mx.random.uniform(shape=(2, 4)) out = mx.vmap(op)(x, y) self.assertTrue(mx.array_equal(out, op(x, y))) out = mx.vmap(op, in_axes=(0, 0), out_axes=0)(x, y) self.assertTrue(mx.array_equal(out, op(x, y))) y = mx.random.uniform(shape=(4, 2)) out = mx.vmap(op, in_axes=(0, 1), out_axes=0)(x, y) self.assertTrue(mx.array_equal(out, op(x, y.T))) out = mx.vmap(op, in_axes=(0, 1), out_axes=1)(x, y) self.assertTrue(mx.array_equal(out, op(x, y.T).T)) def test_tree(self): def my_fun(tree): return (tree["a"] + tree["b"][0]) * tree["b"][1] tree = { "a": mx.random.uniform(shape=(2, 4)), "b": ( mx.random.uniform(shape=(2, 4)), mx.random.uniform(shape=(2, 4)), ), } out = mx.vmap(my_fun)(tree) expected = my_fun(tree) self.assertTrue(mx.array_equal(out, my_fun(tree))) with self.assertRaises(ValueError): mx.vmap(my_fun, in_axes={"a": 0, "b": ((0, 0), 0)}, out_axes=0)(tree) out = mx.vmap(my_fun, in_axes={"a": 0, "b": 0}, out_axes=0)(tree) self.assertTrue(mx.array_equal(out, my_fun(tree))) out = mx.vmap(my_fun, in_axes={"a": 0, "b": (0, 0)}, out_axes=0)(tree) self.assertTrue(mx.array_equal(out, my_fun(tree))) tree = { "a": mx.random.uniform(shape=(2, 4)), "b": ( mx.random.uniform(shape=(4, 2)), mx.random.uniform(shape=(4, 2)), ), } out = mx.vmap(my_fun, in_axes={"a": 0, "b": (1, 1)}, out_axes=0)(tree) expected = (tree["a"] + tree["b"][0].T) * tree["b"][1].T self.assertTrue(mx.array_equal(out, expected)) def my_fun(x, y): return {"a": x + y, "b": x * y} x = mx.random.uniform(shape=(2, 4)) y = mx.random.uniform(shape=(2, 4)) out = mx.vmap(my_fun, in_axes=0, out_axes=0)(x, y) expected = my_fun(x, y) self.assertTrue(mx.array_equal(out["a"], expected["a"])) self.assertTrue(mx.array_equal(out["b"], expected["b"])) with self.assertRaises(ValueError): mx.vmap(my_fun, in_axes=0, out_axes=(0, 1))(x, y) with self.assertRaises(ValueError): mx.vmap(my_fun, in_axes=0, out_axes={"a": 0, "c": 1})(x, y) out = mx.vmap(my_fun, in_axes=0, out_axes={"a": 1, "b": 0})(x, y) expected = my_fun(x, y) self.assertTrue(mx.array_equal(out["a"].T, expected["a"])) self.assertTrue(mx.array_equal(out["b"], expected["b"])) def test_vmap_indexing(self): x = mx.arange(16).reshape(2, 2, 2, 2) inds = mx.array([[0, 1, 0], [1, 1, 0]]) out = mx.vmap(lambda x, y: x[y], in_axes=(0, 0))(x, inds) expected = mx.array( [ [[[0, 1], [2, 3]], [[4, 5], [6, 7]], [[0, 1], [2, 3]]], [[[12, 13], [14, 15]], [[12, 13], [14, 15]], [[8, 9], [10, 11]]], ] ) self.assertTrue(mx.array_equal(out, expected)) out = mx.vmap(lambda x, y: x[y], in_axes=(0, None))(x, inds) expected = mx.array( [ [ [[[0, 1], [2, 3]], [[4, 5], [6, 7]], [[0, 1], [2, 3]]], [[[4, 5], [6, 7]], [[4, 5], [6, 7]], [[0, 1], [2, 3]]], ], [ [[[8, 9], [10, 11]], [[12, 13], [14, 15]], [[8, 9], [10, 11]]], [[[12, 13], [14, 15]], [[12, 13], [14, 15]], [[8, 9], [10, 11]]], ], ] ) self.assertTrue(mx.array_equal(out, expected)) out = mx.vmap(lambda x, y: x[y], in_axes=(None, 0))(x, inds) expected = mx.array( [ [ [[[0, 1], [2, 3]], [[4, 5], [6, 7]]], [[[8, 9], [10, 11]], [[12, 13], [14, 15]]], [[[0, 1], [2, 3]], [[4, 5], [6, 7]]], ], [ [[[8, 9], [10, 11]], [[12, 13], [14, 15]]], [[[8, 9], [10, 11]], [[12, 13], [14, 15]]], [[[0, 1], [2, 3]], [[4, 5], [6, 7]]], ], ] ) self.assertTrue(mx.array_equal(out, expected)) inds2 = mx.array([[0, 1, 0], [0, 1, 0]]) out = mx.vmap(lambda x, y, z: x[y, z], in_axes=(None, 0, 0))(x, inds, inds2) expected = mx.array( [ [[[0, 1], [2, 3]], [[12, 13], [14, 15]], [[0, 1], [2, 3]]], [[[8, 9], [10, 11]], [[12, 13], [14, 15]], [[0, 1], [2, 3]]], ] ) self.assertTrue(mx.array_equal(out, expected)) def test_vmap_reduce(self): a = mx.ones((5, 5), mx.int32) out = mx.vmap(lambda x: x.sum())(a) self.assertTrue(mx.array_equal(out, mx.full((5,), 5))) out = mx.vmap(lambda x: x.sum(keepdims=True))(a) self.assertTrue(mx.array_equal(out, mx.full((5, 1), 5))) out = mx.vmap(lambda x: x.sum(axis=0))(a) self.assertTrue(mx.array_equal(out, mx.full((5,), 5))) a = mx.ones((5, 3, 2), mx.int32) out = mx.vmap(lambda x: x.sum(axis=(0, 1)))(a) self.assertTrue(mx.array_equal(out, mx.full((5,), 6))) a = mx.ones((5, 3, 2), mx.int32) out = mx.vmap(lambda x: x.sum(axis=(0, 1)), in_axes=(1,))(a) self.assertTrue(mx.array_equal(out, mx.full((3,), 10))) a = mx.ones((5, 3, 2), mx.int32) out = mx.vmap(lambda x: x.sum(axis=(0, 1)), in_axes=(2,))(a) self.assertTrue(mx.array_equal(out, mx.full((2,), 15))) def test_vmap_argreduce(self): a = mx.array([[1, 2, 3], [2, 3, 1]]) out = mx.vmap(lambda x: mx.argmin(x))(a) expected = mx.array([0, 2]) self.assertTrue(mx.array_equal(out, expected)) out = mx.vmap(lambda x: mx.argmax(x))(a) expected = mx.array([2, 1]) self.assertTrue(mx.array_equal(out, expected)) def test_vmap_mean(self): a = mx.arange(8).reshape(2, 4) out = mx.vmap(mx.mean)(a) expected = mx.mean(a, axis=1) self.assertTrue(mx.allclose(out, expected)) a = mx.arange(16).reshape(2, 2, 4) out = mx.vmap(mx.vmap(mx.mean))(a) expected = mx.mean(a, axis=2) self.assertTrue(mx.allclose(out, expected)) def test_mismatch_input_sizes(self): a = mx.ones((10, 1)) b = mx.ones((1, 1, 1, 5)) with self.assertRaises(ValueError): out = mx.vmap(lambda x, y: x + y)(a, b) b = mx.ones((10, 5)) with self.assertRaises(ValueError): out = mx.vmap(lambda x, y: x + y, in_axes=(0, 1))(a, b) def test_vmap_matmul(self): a = mx.random.uniform(shape=(2, 3, 4)) b = mx.random.uniform(shape=(4, 3)) # matmul out = mx.vmap(mx.matmul, in_axes=(0, None))(a, b) self.assertTrue(mx.allclose(out, a @ b)) # addmm c = mx.random.uniform(shape=(3,)) out = mx.vmap(mx.addmm, in_axes=(None, 0, None))(c, a, b) self.assertTrue(mx.allclose(out, mx.addmm(c, a, b))) b = mx.random.uniform(shape=(4, 2)) # matmul out = mx.vmap(mx.matmul, in_axes=(1, None), out_axes=(1,))(a, b) expected = mx.moveaxis(mx.moveaxis(a, 1, 0) @ b, 0, 1) self.assertTrue(mx.allclose(out, expected)) # addmm c = mx.random.uniform(shape=(2,)) out = mx.vmap(mx.addmm, in_axes=(None, 1, None))(c, a, b) self.assertTrue(mx.allclose(out, mx.addmm(c, mx.moveaxis(a, 1, 0), b))) a = mx.random.uniform(shape=(2, 3, 4)) b = mx.random.uniform(shape=(4, 2, 3)) # matmul out = mx.vmap(mx.matmul, in_axes=(0, 1))(a, b) expected = a @ mx.moveaxis(b, 1, 0) self.assertTrue(mx.allclose(out, expected)) # addmm c = mx.random.uniform(shape=(3, 3, 2)) out = mx.vmap(mx.addmm, in_axes=(2, 0, 1))(c, a, b) expected = mx.addmm(mx.moveaxis(c, 2, 0), a, mx.moveaxis(b, 1, 0)) self.assertTrue(mx.allclose(out, expected)) def test_vmap_svd(self): a = mx.random.uniform(shape=(3, 4, 2)) cpu_svd_full = lambda x: mx.linalg.svd(x, compute_uv=True, stream=mx.cpu) cpu_svd_singular = lambda x: mx.linalg.svd(x, compute_uv=False, stream=mx.cpu) # Vmap over the first axis (this is already supported natively by the primitive). Us, Ss, Vts = mx.vmap(cpu_svd_full, in_axes=(0,))(a) self.assertEqual(Us.shape, (a.shape[0], a.shape[1], a.shape[1])) self.assertEqual(Ss.shape, (a.shape[0], a.shape[2])) self.assertEqual(Vts.shape, (a.shape[0], a.shape[2], a.shape[2])) Sv = mx.vmap(cpu_svd_singular, in_axes=(0,))(a) self.assertEqual(Sv.shape, (a.shape[0], a.shape[2])) for i in range(a.shape[0]): M = a[i] U, S, Vt = Us[i], Ss[i], Vts[i] self.assertTrue( mx.allclose(U[:, : len(S)] @ mx.diag(S) @ Vt, M, rtol=1e-5, atol=1e-7) ) self.assertTrue( mx.allclose( mx.linalg.norm(Sv[i]), mx.linalg.norm(M, ord="fro"), rtol=1e-5, atol=1e-7, ) ) # Vmap over the second axis. Us, Ss, Vts = mx.vmap(cpu_svd_full, in_axes=(1,))(a) self.assertEqual(Us.shape, (a.shape[1], a.shape[0], a.shape[0])) self.assertEqual(Ss.shape, (a.shape[1], a.shape[2])) self.assertEqual(Vts.shape, (a.shape[1], a.shape[2], a.shape[2])) Sv = mx.vmap(cpu_svd_singular, in_axes=(1,))(a) self.assertEqual(Sv.shape, (a.shape[1], a.shape[2])) for i in range(a.shape[1]): M = a[:, i, :] U, S, Vt = Us[i], Ss[i], Vts[i] self.assertTrue( mx.allclose(U[:, : len(S)] @ mx.diag(S) @ Vt, M, rtol=1e-5, atol=1e-7) ) self.assertTrue( mx.allclose( mx.linalg.norm(Sv[i]), mx.linalg.norm(M, ord="fro"), rtol=1e-5, atol=1e-7, ) ) def test_vmap_inverse(self): mx.random.seed(42) a = mx.random.uniform(shape=(3, 4, 4)) cpu_inv = lambda x: mx.linalg.inv(x, stream=mx.cpu) # Vmap over the first axis (this is already supported natively by the primitive). invs = mx.vmap(cpu_inv, in_axes=(0,))(a) for i in range(a.shape[0]): self.assertTrue( mx.allclose(a[i] @ invs[i], mx.eye(a.shape[1]), rtol=1e-4, atol=1e-5) ) a = mx.random.uniform(shape=(4, 3, 4)) # Without vmapping, each input matrix is not square. with self.assertRaises(ValueError): mx.eval(cpu_inv(a)) # Vmap over the second axis. invs = mx.vmap(cpu_inv, in_axes=(1,))(a) for i in range(a.shape[1]): self.assertTrue( mx.allclose( a[:, i, :] @ invs[i], mx.eye(a.shape[0]), rtol=1e-4, atol=1e-5 ) ) def test_vmap_gather(self): def gather(a, idx): return a[idx] a = mx.array([[1, 2], [3, 4]]) idx = mx.array(0) out = mx.vmap(gather, (0, None))(a, idx) self.assertTrue(mx.array_equal(out, mx.array([1, 3]))) out = mx.vmap(gather, (1, None))(a, idx) self.assertTrue(mx.array_equal(out, mx.array([1, 2]))) idx = mx.array([0, 1]) out = mx.vmap(gather, (0, 0))(a, idx) self.assertTrue(mx.array_equal(out, mx.array([1, 4]))) a = mx.ones((2, 3, 4)) idx = mx.zeros(4, mx.int32) out = mx.vmap(gather, (2, 0))(a, idx) self.assertEqual(out.shape, (4, 3)) f = mx.vmap(gather, (0, None)) f = mx.vmap(gather, (0, 0)) out = f(mx.ones((2, 3, 4)), mx.zeros(2, dtype=mx.int32)) self.assertEqual(out.shape, (2, 4)) def gather(a, idxa, idxb): return a[idxa, idxb] a = mx.ones((2, 3, 4)) idxa = mx.zeros((2, 3), mx.int32) idxb = mx.zeros(3, mx.int32) out = mx.vmap(gather, (0, 0, None))(a, idxa, idxb) self.assertEqual(out.shape, (2, 3)) idxa = mx.zeros((3, 1, 2), mx.int32) idxb = mx.zeros((2, 3, 1, 2), mx.int32) out = mx.vmap(gather, (0, None, 0))(a, idxa, idxb) self.assertEqual(out.shape, (2, 3, 1, 2)) idxa = mx.zeros((3, 1, 2), mx.int32) idxb = mx.zeros((3, 1, 2, 2), mx.int32) out = mx.vmap(gather, (0, None, 3))(a, idxa, idxb) self.assertEqual(out.shape, (2, 3, 1, 2)) def test_vmap_scatter(self): def scatter(a): a[mx.array(0)] = mx.array(0.0) return a a = mx.array([[1.0, 2.0, 3.0], [2.0, 3.0, 4.0]]) out = mx.vmap(scatter)(a) expected = mx.array([[0.0, 2.0, 3.0], [0.0, 3.0, 4.0]]) self.assertTrue(mx.allclose(out, expected)) out = mx.vmap(scatter, in_axes=(1,), out_axes=1)(a) expected = mx.array([[0.0, 0.0, 0.0], [2.0, 3.0, 4.0]]) self.assertTrue(mx.allclose(out, expected)) def scatter_add(a): return a.at[mx.array(0)].add(mx.array(1.0)) a = mx.array([[1.0, 2.0, 3.0], [2.0, 3.0, 4.0]]) out = mx.vmap(scatter_add)(a) expected = mx.array([[2.0, 2.0, 3.0], [3.0, 3.0, 4.0]]) self.assertTrue(mx.allclose(out, expected)) out = mx.vmap(scatter_add, in_axes=(1,), out_axes=1)(a) expected = mx.array([[2.0, 3.0, 4.0], [2.0, 3.0, 4.0]]) self.assertTrue(mx.allclose(out, expected)) # Multiple indices def scatter(a): a[mx.array([0, 1]), mx.array([0, 1])] = mx.array((1.0, 1.0)) return a a = mx.zeros((3, 3, 3)) expected = mx.repeat(scatter(mx.zeros((3, 3)))[None], 3, axis=0) out = mx.vmap(scatter, in_axes=(0,), out_axes=0)(a) self.assertTrue(mx.allclose(out, expected)) expected = mx.zeros((3, 3, 3)) expected[0, :, 0] = 1 expected[1, :, 1] = 1 out = mx.vmap(scatter, in_axes=(1,), out_axes=1)(a) self.assertTrue(mx.allclose(out, expected)) expected = mx.zeros((3, 3, 3)) expected[0, 0, :] = 1 expected[1, 1, :] = 1 out = mx.vmap(scatter, in_axes=(2,), out_axes=2)(a) self.assertTrue(mx.allclose(out, expected)) # vmap over src and indices def scatter(a, idx): a[idx] = mx.array(1.0) return a a = mx.zeros((3, 4)) idx = mx.array([0, 1, 2]) out = mx.vmap(scatter, in_axes=(0, 0), out_axes=0)(a, idx) self.assertTrue(mx.allclose(out, mx.eye(n=3, m=4))) # vmap over only indices out = mx.vmap(scatter, in_axes=(None, 0), out_axes=0)(a, idx) expected = mx.zeros((3, 3, 4)) expected[0, 0] = 1 expected[1, 1] = 1 expected[2, 2] = 1 self.assertTrue(mx.allclose(out, expected)) # vmap over src, indices, updates def scatter(a, idx, updates): a[idx] = updates return a a = mx.zeros((3, 4)) idx = mx.array([0, 1, 2]) updates = mx.array([1, 2, 3]) out = mx.vmap(scatter, in_axes=(0, 0, 0), out_axes=0)(a, idx, updates) expected = mx.diag(mx.array([1, 2, 3]), k=-1)[1:] self.assertTrue(mx.allclose(out, expected)) # vmap over only updates def scatter(a, idx, updates): a[idx] = updates return a a = mx.zeros((3, 4)) idx = mx.array([0]) updates = mx.array([1, 2, 3]) out = mx.vmap(scatter, in_axes=(None, None, 0), out_axes=0)(a, idx, updates) expected = mx.zeros((3, 3, 4)) expected[:, 0] = mx.array([1, 2, 3])[:, None] self.assertTrue(mx.allclose(out, expected)) def test_vmap_const_func(self): a = mx.random.uniform(shape=(2, 3, 4)) b = mx.random.uniform(shape=(4, 3)) def const_func(a, b): return mx.array(2) out = mx.vmap(const_func, in_axes=(0, None))(a, b) self.assertTrue(mx.array_equal(mx.full((2,), 2), out)) out = mx.vmap(const_func, in_axes=(None, 0))(a, b) self.assertTrue(mx.array_equal(mx.full((4,), 2), out)) out = mx.vmap(const_func, in_axes=(1, 1))(a, b) self.assertTrue(mx.array_equal(mx.full((3,), 2), out)) with self.assertRaises(ValueError): out = mx.vmap(const_func, in_axes=(None, None))(a, b) with self.assertRaises(ValueError): out = mx.vmap(const_func, in_axes=(0, 0))(a, b) def test_vmap_concatenate(self): x = mx.random.uniform(shape=(2, 2, 2)) def cat_fun(x, y): return mx.concatenate([x, y], axis=1) def cat_constant(x): y = mx.ones((2, 1)) return mx.concatenate([x, y], 1) out = mx.vmap(cat_fun, in_axes=(0, 2))(x, x) target = mx.stack( [mx.concatenate([x[i], x[:, :, i]], axis=1) for i in range(2)] ) self.assertTrue(mx.array_equal(out, target)) out = mx.vmap(cat_constant)(x) target = mx.concatenate([x, mx.ones((2, 2, 1))], axis=2) self.assertTrue(mx.array_equal(out, target)) def test_vmap_take_along_axis(self): a = mx.zeros((4, 5, 1)) idx = mx.zeros((2, 4, 1), mx.int32) def fun(a, idx): return mx.take_along_axis(a, idx, axis=0) out = mx.vmap(fun, in_axes=(0, 1))(a, idx) self.assertEqual(out.shape, (4, 2, 1)) idx = mx.zeros((2, 1), mx.int32) out = mx.vmap(fun, in_axes=(0, None))(a, idx) self.assertEqual(out.shape, (4, 2, 1)) a = mx.zeros((5, 1)) idx = mx.zeros((4, 2, 1), mx.int32) out = mx.vmap(fun, in_axes=(None, 0))(a, idx) self.assertEqual(out.shape, (4, 2, 1)) def test_vmap_put_along_axis(self): a = mx.zeros((4, 5, 1)) idx = mx.ones((2, 4, 1), mx.int32) upd = mx.ones((2, 4, 1)) def fun(a, idx, upd): return mx.put_along_axis(a, idx, upd, axis=0) out = mx.vmap(fun, in_axes=(0, 1, 1))(a, idx, upd) self.assertEqual(out.shape, (4, 5, 1)) upd = mx.ones((2, 1)) out = mx.vmap(fun, in_axes=(0, 1, None))(a, idx, upd) self.assertEqual(out.shape, (4, 5, 1)) idx = mx.ones((2, 1), mx.int32) upd = mx.ones((2, 1)) out = mx.vmap(fun, in_axes=(0, None, None))(a, idx, upd) self.assertEqual(out.shape, (4, 5, 1)) a = mx.zeros((5, 1)) idx = mx.ones((2, 4, 1), mx.int32) upd = mx.ones((2, 4, 1)) out = mx.vmap(fun, in_axes=(None, 1, 1))(a, idx, upd) self.assertEqual(out.shape, (4, 5, 1)) def test_vmap_split_vmap(self): def fun(x): a, b = mx.split(x, 2, 1) return mx.concatenate([b, a], 1) x = mx.ones((5, 6, 7)) y = mx.ones((5, 4, 6, 7)) fx = fun(x) fy = mx.vmap(fun, in_axes=1)(y) self.assertEqual(fx.shape, (5, 6, 7)) self.assertEqual(fy.shape, (4, 5, 6, 7)) def test_leaks(self): if mx.metal.is_available(): mem_pre = mx.metal.get_active_memory() else: mem_pre = 0 def outer(): d = {} def f(x): return d["x"] d["f"] = mx.vmap(f) d["x"] = mx.array([0] * 1000) for _ in range(5): outer() gc.collect() if mx.metal.is_available(): mem_post = mx.metal.get_active_memory() else: mem_post = 0 self.assertEqual(mem_pre, mem_post) if __name__ == "__main__": unittest.main()