コード例 #1
0
ファイル: test_lkj_prior.py プロジェクト: xuehaouwa/gpytorch
    def test_lkj_covariance_prior_log_prob_hetsd(self, cuda=False):
        device = torch.device("cuda") if cuda else torch.device("cpu")
        a = torch.tensor([exp(-1), exp(-2)], device=device)
        b = torch.tensor([exp(1), exp(2)], device=device)
        sd_prior = SmoothedBoxPrior(a, b, log_transform=True)
        prior = LKJCovariancePrior(2, torch.tensor(0.5, device=device),
                                   sd_prior)
        self.assertFalse(prior.log_transform)
        S = torch.eye(2, device=device)
        self.assertAlmostEqual(prior.log_prob(S).item(), -4.71958, places=4)
        S = torch.stack(
            [S, torch.tensor([[1.0, 0.5], [0.5, 1]], device=S.device)])
        self.assertTrue(
            approx_equal(prior.log_prob(S),
                         torch.tensor([-4.71958, -4.57574], device=S.device)))
        with self.assertRaises(ValueError):
            prior.log_prob(torch.eye(3, device=device))

        # For eta=1.0 log_prob is flat over all covariance matrices
        prior = LKJCovariancePrior(2, torch.tensor(1.0, device=device),
                                   sd_prior)
        marginal_sd = torch.diagonal(S, dim1=-2, dim2=-1).sqrt()
        log_prob_expected = prior.correlation_prior.C + prior.sd_prior.log_prob(
            marginal_sd)
        self.assertTrue(approx_equal(prior.log_prob(S), log_prob_expected))
コード例 #2
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    def test_lkj_covariance_prior_batch_log_prob(self, cuda=False):
        device = torch.device("cuda") if cuda else torch.device("cpu")
        v = torch.ones(2, 1, device=device)
        sd_prior = SmoothedBoxPrior(exp(-1) * v, exp(1) * v)
        prior = LKJCovariancePrior(2, torch.tensor([0.5, 1.5], device=device), sd_prior)

        S = torch.eye(2, device=device)
        self.assertTrue(approx_equal(prior.log_prob(S), torch.tensor([-3.59981, -2.21351], device=S.device)))
        S = torch.stack([S, torch.tensor([[1.0, 0.5], [0.5, 1]], device=S.device)])
        self.assertTrue(approx_equal(prior.log_prob(S), torch.tensor([-3.59981, -2.35735], device=S.device)))
        with self.assertRaises(ValueError):
            prior.log_prob(torch.eye(3, device=device))
コード例 #3
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    def test_lkj_covariance_prior_batch_log_prob(self, cuda=False):
        device = torch.device("cuda") if cuda else torch.device("cpu")
        v = torch.ones(2, 1, device=device)
        sd_prior = SmoothedBoxPrior(exp(-1) * v, exp(1) * v)
        prior = LKJCovariancePrior(2, torch.tensor([0.5, 1.5], device=device),
                                   sd_prior)
        corr_dist = LKJCholesky(2, torch.tensor([0.5, 1.5], device=device))

        S = torch.eye(2, device=device)
        dist_log_prob = corr_dist.log_prob(S) + sd_prior.log_prob(S.diag())
        self.assertLessEqual((prior.log_prob(S) - dist_log_prob).abs().sum(),
                             1e-4)

        S = torch.stack(
            [S, torch.tensor([[1.0, 0.5], [0.5, 1]], device=S.device)])
        S_chol = torch.linalg.cholesky(S)
        dist_log_prob = corr_dist.log_prob(S_chol) + sd_prior.log_prob(
            torch.diagonal(S, dim1=-2, dim2=-1))
        self.assertLessEqual((prior.log_prob(S) - dist_log_prob).abs().sum(),
                             1e-4)
コード例 #4
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    def test_lkj_covariance_prior_log_prob_hetsd(self, cuda=False):
        device = torch.device("cuda") if cuda else torch.device("cpu")
        a = torch.tensor([exp(-1), exp(-2)], device=device)
        b = torch.tensor([exp(1), exp(2)], device=device)
        sd_prior = SmoothedBoxPrior(a, b)
        prior = LKJCovariancePrior(2, torch.tensor(0.5, device=device),
                                   sd_prior)
        corr_dist = LKJCholesky(2, torch.tensor(0.5, device=device))

        S = torch.eye(2, device=device)
        dist_log_prob = corr_dist.log_prob(S) + sd_prior.log_prob(
            S.diag()).sum()
        self.assertAlmostEqual(prior.log_prob(S), dist_log_prob, places=4)

        S = torch.stack(
            [S, torch.tensor([[1.0, 0.5], [0.5, 1]], device=S.device)])
        S_chol = torch.linalg.cholesky(S)
        dist_log_prob = corr_dist.log_prob(S_chol) + sd_prior.log_prob(
            torch.diagonal(S, dim1=-2, dim2=-1))
        self.assertTrue(approx_equal(prior.log_prob(S), dist_log_prob))