def test_ard(self): a = torch.tensor([[[1, 2], [2, 4]]], dtype=torch.float).repeat(2, 1, 1) b = torch.tensor([[[1, 3], [0, 4]]], dtype=torch.float).repeat(2, 1, 1) lengthscales = torch.tensor([1, 2], dtype=torch.float).view(1, 1, 2) base_kernel = RBFKernel(ard_num_dims=2) base_kernel.initialize(lengthscale=lengthscales) kernel = ScaleKernel(base_kernel) kernel.initialize(outputscale=torch.tensor([3], dtype=torch.float)) kernel.eval() scaled_a = a.div(lengthscales) scaled_b = b.div(lengthscales) actual = (scaled_a.unsqueeze(-2) - scaled_b.unsqueeze(-3)).pow(2).sum(dim=-1).mul_(-0.5).exp() actual.mul_(3) res = kernel(a, b).evaluate() self.assertLess(torch.norm(res - actual), 1e-5) # Diag res = kernel(a, b).diag() actual = torch.cat([actual[i].diag().unsqueeze(0) for i in range(actual.size(0))]) self.assertLess(torch.norm(res - actual), 1e-5) # batch_dims actual = scaled_a.transpose(-1, -2).unsqueeze(-1) - scaled_b.transpose(-1, -2).unsqueeze(-2) actual = actual.pow(2).mul_(-0.5).exp().view(4, 2, 2) actual.mul_(3) res = kernel(a, b, batch_dims=(0, 2)).evaluate() self.assertLess(torch.norm(res - actual), 1e-5) # batch_dims and diag res = kernel(a, b, batch_dims=(0, 2)).diag() actual = torch.cat([actual[i].diag().unsqueeze(0) for i in range(actual.size(0))]) self.assertLess(torch.norm(res - actual), 1e-5)
def test_inherit_active_dims(self): lengthscales = torch.tensor([1, 1], dtype=torch.float) base_kernel = RBFKernel(active_dims=(1, 2), ard_num_dims=2) base_kernel.initialize(lengthscale=lengthscales) kernel = ScaleKernel(base_kernel) kernel.initialize(outputscale=torch.tensor([3], dtype=torch.float)) kernel.eval() self.assertTrue( torch.all(kernel.active_dims == base_kernel.active_dims))
def create_multi_full_kernel(d, J, init_mixin_range=(1.0, 1.0), **kwargs): """Helper to create a sum of full kernels with the options in **kwargs.""" outputscales = _sample_from_range(J, init_mixin_range) total = sum(outputscales) outputscales = [o / total for o in outputscales] subkernels = [] for j in range(0,J): new_kernel = ScaleKernel(create_full_kernel(d, **kwargs)) new_kernel.initialize(outputscale=outputscales[j]) subkernels.append(new_kernel) return gpytorch.kernels.AdditiveKernel(*subkernels)
def make_kernel(active_dim=None): kernel = _map_to_kernel(True, kernel_type, keops, active_dims=active_dim) if hasattr(kernel, 'period_length'): kernel.initialize(period_length=torch.tensor([1.])) else: kernel.initialize(lengthscale=torch.tensor([1.])) kernel = ScaleKernel(kernel) kernel.initialize(outputscale=torch.tensor([1/J])) if ski: kernel = gpytorch.kernels.GridInterpolationKernel(kernel, **ski_options) return kernel
def test_forward(self): gam_kernel = MemoryEfficientGamKernel() x = torch.tensor([[1., 2., 3.], [1.1, 2.2, 3.3]]) K = gam_kernel(x, x).evaluate() k = ScaleKernel(RBFKernel()) k.initialize(outputscale=1.) as_kernel = AdditiveStructureKernel(k, 2) K2 = as_kernel(x, x).evaluate() np.testing.assert_allclose(K.detach().numpy(), K2.detach().numpy(), atol=1e-6)
def test_forward_batch_mode(self): a = torch.Tensor([4, 2, 8]).view(1, 3, 1).repeat(4, 1, 1) b = torch.Tensor([0, 2]).view(1, 2, 1).repeat(4, 1, 1) lengthscale = 2 base_kernel = RBFKernel().initialize(log_lengthscale=math.log(lengthscale)) kernel = ScaleKernel(base_kernel, batch_size=4) kernel.initialize(log_outputscale=torch.Tensor([1, 2, 3, 4]).log()) kernel.eval() base_actual = torch.Tensor([[16, 4], [4, 0], [64, 36]]).mul_(-0.5).div_(lengthscale ** 2).exp() actual = base_actual.unsqueeze(0).mul(torch.Tensor([1, 2, 3, 4]).view(4, 1, 1)) res = kernel(a, b).evaluate() self.assertLess(torch.norm(res - actual), 1e-5)
def test_forward(self): a = torch.Tensor([4, 2, 8]).view(3, 1) b = torch.Tensor([0, 2]).view(2, 1) lengthscale = 2 base_kernel = RBFKernel().initialize(log_lengthscale=math.log(lengthscale)) kernel = ScaleKernel(base_kernel) kernel.initialize(log_outputscale=torch.Tensor([3]).log()) kernel.eval() actual = torch.Tensor([[16, 4], [4, 0], [64, 36]]).mul_(-0.5).div_(lengthscale ** 2).exp() actual = actual * 3 res = kernel(a, b).evaluate() self.assertLess(torch.norm(res - actual), 1e-5)
def test_degree1(self): AddK = NewtonGirardAdditiveKernel(RBFKernel(ard_num_dims=3), 3, 1) self.assertEqual(AddK.base_kernel.lengthscale.numel(), 3) self.assertEqual(AddK.outputscale.numel(), 1) testvals = torch.tensor([[1, 2, 3], [7, 5, 2]], dtype=torch.float) add_k_val = AddK(testvals, testvals).evaluate() manual_k = ScaleKernel(AdditiveKernel(RBFKernel(active_dims=0), RBFKernel(active_dims=1), RBFKernel(active_dims=2))) manual_k.initialize(outputscale=1.) manual_add_k_val = manual_k(testvals, testvals).evaluate() # np.testing.assert_allclose(add_k_val.detach().numpy(), manual_add_k_val.detach().numpy(), atol=1e-5) self.assertTrue(torch.allclose(add_k_val, manual_add_k_val, atol=1e-5))
def test_ard(self): base_k = RBFKernel(ard_num_dims=3) base_k.initialize(lengthscale=[1., 2., 3.]) AddK = NewtonGirardAdditiveKernel(base_k, 3, max_degree=1) testvals = torch.tensor([[1, 2, 3], [7, 5, 2]], dtype=torch.float) add_k_val = AddK(testvals, testvals).evaluate() ks = [] for i in range(3): k = RBFKernel(active_dims=i) k.initialize(lengthscale=i + 1) ks.append(k) manual_k = ScaleKernel(AdditiveKernel(*ks)) manual_k.initialize(outputscale=1.) manual_add_k_val = manual_k(testvals, testvals).evaluate() # np.testing.assert_allclose(add_k_val.detach().numpy(), manual_add_k_val.detach().numpy(), atol=1e-5) self.assertTrue(torch.allclose(add_k_val, manual_add_k_val, atol=1e-5))
def test_ard_batch(self): a = torch.tensor([[[1, 2, 3], [2, 4, 0]], [[-1, 1, 2], [2, 1, 4]]], dtype=torch.float) b = torch.tensor([[[1, 3, 1]], [[2, -1, 0]]], dtype=torch.float).repeat(1, 2, 1) lengthscales = torch.tensor([[[1, 2, 1]]], dtype=torch.float) base_kernel = RBFKernel(batch_shape=torch.Size([2]), ard_num_dims=3) base_kernel.initialize(lengthscale=lengthscales) kernel = ScaleKernel(base_kernel, batch_shape=torch.Size([2])) kernel.initialize(outputscale=torch.tensor([1, 2], dtype=torch.float)) kernel.eval() scaled_a = a.div(lengthscales) scaled_b = b.div(lengthscales) actual = (scaled_a.unsqueeze(-2) - scaled_b.unsqueeze(-3)).pow(2).sum(dim=-1).mul_(-0.5).exp() actual[1].mul_(2) res = kernel(a, b).evaluate() self.assertLess(torch.norm(res - actual), 1e-5) # diag res = kernel(a, b).diag() actual = torch.cat( [actual[i].diag().unsqueeze(0) for i in range(actual.size(0))]) self.assertLess(torch.norm(res - actual), 1e-5) # batch_dims double_batch_a = scaled_a.transpose(-1, -2) double_batch_b = scaled_b.transpose(-1, -2) actual = double_batch_a.unsqueeze(-1) - double_batch_b.unsqueeze(-2) actual = actual.pow(2).mul_(-0.5).exp() actual[1, :, :, :].mul_(2) res = kernel(a, b, last_dim_is_batch=True).evaluate() self.assertLess(torch.norm(res - actual), 1e-5) # batch_dims and diag res = kernel(a, b, last_dim_is_batch=True).diag() actual = actual.diagonal(dim1=-2, dim2=-1) self.assertLess(torch.norm(res - actual), 1e-5)
def test_degree3(self): # just make sure it doesn't break here. AddK = NewtonGirardAdditiveKernel(RBFKernel(ard_num_dims=3), 3, 3) self.assertEqual(AddK.base_kernel.lengthscale.numel(), 3) self.assertEqual(AddK.outputscale.numel(), 3) testvals = torch.tensor([[1, 2, 3], [7, 5, 2]], dtype=torch.float) add_k_val = AddK(testvals, testvals).evaluate() manual_k1 = ScaleKernel( AdditiveKernel(RBFKernel(active_dims=0), RBFKernel(active_dims=1), RBFKernel(active_dims=2))) manual_k1.initialize(outputscale=1 / 3) manual_k2 = ScaleKernel( AdditiveKernel(RBFKernel(active_dims=[0, 1]), RBFKernel(active_dims=[1, 2]), RBFKernel(active_dims=[0, 2]))) manual_k2.initialize(outputscale=1 / 3) manual_k3 = ScaleKernel(AdditiveKernel(RBFKernel())) manual_k3.initialize(outputscale=1 / 3) manual_k = AdditiveKernel(manual_k1, manual_k2, manual_k3) manual_add_k_val = manual_k(testvals, testvals).evaluate() # np.testing.assert_allclose(add_k_val.detach().numpy(), manual_add_k_val.detach().numpy(), atol=1e-5) self.assertTrue(torch.allclose(add_k_val, manual_add_k_val, atol=1e-5))
def test_initialize_outputscale_batch(self): kernel = ScaleKernel(RBFKernel(), batch_size=2) ls_init = torch.tensor([3.14, 4.13]) kernel.initialize(outputscale=ls_init) actual_value = ls_init.view_as(kernel.outputscale) self.assertLess(torch.norm(kernel.outputscale - actual_value), 1e-5)
def test_initialize_outputscale(self): kernel = ScaleKernel(RBFKernel()) kernel.initialize(outputscale=3.14) actual_value = torch.tensor(3.14).view_as(kernel.outputscale) self.assertLess(torch.norm(kernel.outputscale - actual_value), 1e-5)