test_torch.py 文件源码

def test_trtrs(self):
        a = torch.Tensor(((6.80, -2.11,  5.66,  5.97,  8.23),
                        (-6.05, -3.30,  5.36, -4.44,  1.08),
                        (-0.45,  2.58, -2.70,  0.27,  9.04),
                        (8.32,  2.71,  4.35, -7.17,  2.14),
                        (-9.67, -5.14, -7.26,  6.08, -6.87))).t()
        b = torch.Tensor(((4.02,  6.19, -8.22, -7.57, -3.03),
                        (-1.56,  4.00, -8.67,  1.75,  2.86),
                        (9.81, -4.09, -4.57, -8.61,  8.99))).t()

        U = torch.triu(a)
        L = torch.tril(a)

        # solve Ux = b
        x = torch.trtrs(b, U)[0]
        self.assertLessEqual(b.dist(torch.mm(U, x)), 1e-12)
        x = torch.trtrs(b, U, True, False, False)[0]
        self.assertLessEqual(b.dist(torch.mm(U, x)), 1e-12)

        # solve Lx = b
        x = torch.trtrs(b, L, False)[0]
        self.assertLessEqual(b.dist(torch.mm(L, x)), 1e-12)
        x = torch.trtrs(b, L, False, False, False)[0]
        self.assertLessEqual(b.dist(torch.mm(L, x)), 1e-12)

        # solve U'x = b
        x = torch.trtrs(b, U, True, True)[0]
        self.assertLessEqual(b.dist(torch.mm(U.t(), x)), 1e-12)
        x = torch.trtrs(b, U, True, True, False)[0]
        self.assertLessEqual(b.dist(torch.mm(U.t(), x)), 1e-12)

        # solve U'x = b by manual transposition
        y = torch.trtrs(b, U.t(), False, False)[0]
        self.assertLessEqual(x.dist(y), 1e-12)

        # solve L'x = b
        x = torch.trtrs(b, L, False, True)[0]
        self.assertLessEqual(b.dist(torch.mm(L.t(), x)), 1e-12)
        x = torch.trtrs(b, L, False, True, False)[0]
        self.assertLessEqual(b.dist(torch.mm(L.t(), x)), 1e-12)

        # solve L'x = b by manual transposition
        y = torch.trtrs(b, L.t(), True, False)[0]
        self.assertLessEqual(x.dist(y), 1e-12)

        # test reuse
        res1 = torch.trtrs(b,a)[0]
        ta = torch.Tensor()
        tb = torch.Tensor()
        torch.trtrs(tb,ta,b,a)
        self.assertEqual(res1, tb, 0)
        tb.zero_()
        torch.trtrs(tb,ta,b,a)
        self.assertEqual(res1, tb, 0)