def test__initialize_weights_case3(self): """ multi-init """ random_state = np.random.RandomState(12) n_init = 3 means_init_true = random_state.rand(n_init, self.td.K, self.td.P) weights_init_true = random_state.rand(n_init, self.td.K) weights_init_true /= weights_init_true.sum(axis=1)[:, np.newaxis] gmm = GaussianMixture(n_components=self.td.K, num_feat_full=self.td.P, num_feat_comp=self.td.Q, num_feat_shared=self.td.Qs, num_samp=self.td.N, transform=self.td.transform, D_indices=self.td.D_indices, mask=self.td.mask, means_init=means_init_true, weights_init=weights_init_true, n_init=n_init, covariance_type='diag', random_state=random_state) gmm.fit_sparsifier(X=self.td.X) # init means twice to cycle covariances _ = gmm._initialize_means() means_init = gmm._initialize_means() weights_init_test = gmm._initialize_weights(means_init) self.assertArrayEqual(weights_init_test, weights_init_true[1])
def test_pairwise_mahalanobis_distances(self): """ pairwise_mahalanobis_distances is a Sparsifier function, but a use case here made me suspect that it's wrong. To confirm this I'm putting a test here first. Will need to make a new one (and probably ammend existing ones that are currently passing but shouldn't be) in that test suite once I am convinced it's the culprit. """ cov_type = 'spherical' rs = np.random.RandomState(10) gmm = GaussianMixture(n_components=3, num_feat_full=5, num_feat_comp=3, num_feat_shared=2, num_samp=4, transform=None, mask=None, D_indices=None, covariance_type=cov_type, random_state=rs) gmm.fit_sparsifier(X=self.td.X) means = rs.rand(gmm.n_components, gmm.num_feat_full) covariances = rs.rand(gmm.n_components) mahadist_test = gmm.pairwise_mahalanobis_distances( means, covariances, cov_type)**2 #undo the rescaling due to compression mahadist_test *= gmm.num_feat_comp / gmm.num_feat_full mahadist_true = np.zeros_like(mahadist_test) for data_ind in range(gmm.num_samp): for comp_ind in range(gmm.n_components): mahadist_true[data_ind, comp_ind] = 1/covariances[comp_ind] * \ np.linalg.norm(gmm.RHDX[data_ind] - means[comp_ind][gmm.mask[data_ind]])**2 self.assertArrayEqual(mahadist_test, mahadist_true)
def test__initialize_covariances_case4(self): """ diagonal covariance, multi-init. """ random_state = np.random.RandomState(12) n_init = 3 means_init_true = random_state.rand(n_init, self.td.K, self.td.P) covariances_init_true = random_state.rand(n_init, self.td.K, self.td.P) gmm = GaussianMixture(n_components=self.td.K, num_feat_full=self.td.P, num_feat_comp=self.td.Q, num_feat_shared=self.td.Qs, num_samp=self.td.N, transform=self.td.transform, D_indices=self.td.D_indices, mask=self.td.mask, means_init=means_init_true, covariances_init=covariances_init_true, covariance_type='diag', n_init=n_init, random_state=random_state) gmm.fit_sparsifier(X=self.td.X) # init means twice to cycle covariances _ = gmm._initialize_means() means_init = gmm._initialize_means() covariances_init_test = gmm._initialize_covariances(means_init) self.assertArrayEqual(covariances_init_test, covariances_init_true[1])
def test__compute_log_prob_spherical_shared_compression(self): """ Compare the log_prob computation to that of sklearn with shared compression. Spherical covariances. """ cov_type = 'spherical' rs = np.random.RandomState(10) gmm = GaussianMixture(n_components=3, num_feat_full=5, num_feat_comp=3, num_feat_shared=3, num_samp=4, transform=None, mask=None, D_indices=None, covariance_type=cov_type, random_state=rs) gmm.fit_sparsifier(X=self.td.X) means = rs.rand(gmm.n_components, gmm.num_feat_full) covariances = rs.rand(gmm.n_components) log_prob_test = gmm._compute_log_prob(means, covariances, cov_type) log_prob_true = np.zeros((gmm.num_samp, gmm.n_components)) for data_ind in range(gmm.num_samp): for comp_ind in range(gmm.n_components): true_const = gmm.num_feat_comp * np.log(2 * np.pi) true_logdet = gmm.num_feat_comp * np.log(covariances[comp_ind]) true_mahadist = 1/covariances[comp_ind] * \ np.linalg.norm(gmm.RHDX[data_ind] - means[comp_ind][gmm.mask[data_ind]])**2 log_prob_true[data_ind, comp_ind] = -.5*(true_const + \ true_logdet + true_mahadist) self.assertArrayEqual(log_prob_test, log_prob_true)
def test__estimate_gaussian_means_and_covariances_diagonal_no_compression( self): """ Test _estimate_gaussian_means_and_covariances against hard-coded example. Should be redundant with test__estimate_gaussian_parameters_* tests above, which test against sklearn's results. """ X = np.array([[0, 1, 0, 0], [1, 0, 0, 0], [0, 0, 1, 2]], dtype=np.float64) gmm = GaussianMixture(n_components=2, num_feat_full=4, num_feat_comp=4, num_feat_shared=4, num_samp=3, transform=None, D_indices=None, mask=None, reg_covar=0) gmm.fit_sparsifier(X=X) # note: columns should sum to 1, but don't have to because the weighted # means computation has to renormalize anyway to account for the mask resp = np.array([[.6, .3], [.4, .2], [0, .5]], dtype=np.float64) means, covariances = gmm._estimate_gaussian_means_and_covariances( resp, 'diag') correct_means = np.array([[.4, .6, .0, .0], [.2, .3, .5, 1.]], dtype=np.float64) correct_covariances = np.array([[.24, .24, 0, 0], [.16, .21, .25, 1]], dtype=np.float64) self.assertArrayEqual(correct_means, means) self.assertArrayEqual(correct_covariances, covariances)
def test__estimate_gaussian_parameters_diagonal_no_compression(self): """ Test _estiamte_gaussian_parameters against sklearn's implementation. Diagonal covariances, no compression. """ cov_type = 'diag' reg_covar = 1e-6 gmm = GaussianMixture(n_components=3, num_feat_full=5, num_feat_comp=5, num_feat_shared=5, num_samp=4, transform=None, mask=None, D_indices=None, covariance_type=cov_type, reg_covar=reg_covar) gmm.fit_sparsifier(X=self.td.X) resp = np.random.rand(gmm.num_samp, gmm.n_components) weights_test, means_test, covariances_test = gmm._estimate_gaussian_parameters( resp, cov_type) # skl counts_true, means_true, covariances_true = _estimate_gaussian_parameters( self.td.X, resp, reg_covar, cov_type) # skl returns counts instead of weights. weights_true = counts_true / gmm.num_samp self.assertArrayEqual(weights_test, weights_true) self.assertArrayEqual(means_test, means_true) self.assertArrayEqual(covariances_test, covariances_true)
def test__init_resp_from_means(self): gmm = GaussianMixture(n_components=3, num_feat_full=5, num_feat_comp=3, num_feat_shared=1, num_samp=4, transform='dct', D_indices=self.td.D_indices, mask=self.td.mask) gmm.fit_sparsifier(X=self.td.X) resp_test = gmm._init_resp_from_means(self.td.U) resp_correct = np.array([[0, 1, 0], [1, 0, 0], [0, 1, 0], [0, 1, 0]], dtype=int)
def test_fit_sparsifier(self): gmm = GaussianMixture(n_components=3, num_feat_full=5, num_feat_comp=3, num_feat_shared=1, num_samp=4, transform='dct', D_indices=self.td.D_indices, mask=self.td.mask) gmm.fit_sparsifier(X=self.td.X) self.assertArrayEqual(self.td.RHDX, gmm.RHDX) self.assertArrayEqual(self.td.mask, gmm.mask) self.assertEqual(self.td.N, gmm.num_samp) self.assertEqual(self.td.Q, gmm.num_feat_comp) self.assertEqual(self.td.P, gmm.num_feat_full)
def test__initialize_parameters(self): """ Only tests if it runs. """ init_params = 'random' means_init = None gmm = GaussianMixture(n_components=3, num_feat_full=5, num_feat_comp=3, num_feat_shared=1, num_samp=4, transform='dct', D_indices=self.td.D_indices, mask=self.td.mask, init_params=init_params, means_init=means_init) gmm.fit_sparsifier(HDX=self.td.HDX) gmm._initialize_parameters()
def test__initialize_means_case1(self): """ means_init is a 2D array. """ random_state = np.random.RandomState(12) means_init_true = random_state.rand(self.td.K, self.td.P) gmm = GaussianMixture(n_components=self.td.K, num_feat_full=self.td.P, num_feat_comp=self.td.Q, num_feat_shared=self.td.Qs, num_samp=self.td.N, transform=self.td.transform, D_indices=self.td.D_indices, mask=self.td.mask, means_init=means_init_true, random_state=random_state) gmm.fit_sparsifier(X=self.td.X) means_init_test = gmm._initialize_means() self.assertArrayEqual(means_init_test, means_init_true)
def test_hand_computation_of_log_prob_vs_sklearn(self): """ Something seems wrong with my mahadist computation. Before digging further into the C library to find the error, I want to make sure that the results I think it should give are right. One way to gather evidence in favor of this conclusion is to use the result in the computation of the log probability (this is what led me here in the first place). This test does so, and consequently doesn't actually test any of the code in gmm.py. For this to work the mask must be entirely shared. """ cov_type = 'spherical' rs = np.random.RandomState(10) gmm = GaussianMixture(n_components=3, num_feat_full=5, num_feat_comp=3, num_feat_shared=3, num_samp=4, transform=None, mask=None, D_indices=None, covariance_type=cov_type, random_state=rs) gmm.fit_sparsifier(X=self.td.X) means = rs.rand(gmm.n_components, gmm.num_feat_full) covariances = rs.rand(gmm.n_components) precisions = _compute_precision_cholesky(covariances, cov_type) # this is where we need the mask to be shared, so that all mask rows # equal mask[0] masked_means = means[:, gmm.mask[0]] log_prob_true = _estimate_log_gaussian_prob(gmm.RHDX, masked_means, precisions, cov_type) log_prob_test = np.zeros((gmm.num_samp, gmm.n_components)) for data_ind in range(gmm.num_samp): for comp_ind in range(gmm.n_components): test_const = gmm.num_feat_comp * np.log(2 * np.pi) test_logdet = gmm.num_feat_comp * np.log(covariances[comp_ind]) test_mahadist = 1/covariances[comp_ind] * \ np.linalg.norm(gmm.RHDX[data_ind] - means[comp_ind][gmm.mask[data_ind]])**2 log_prob_test[data_ind, comp_ind] = -.5*(test_const + \ test_logdet + test_mahadist) self.assertArrayEqual(log_prob_test, log_prob_true)
def test__initialize_means_case4(self): """ means_init is None, init_params is 'random'. Only checks that the initialized means are of the correct shape. """ random_state = np.random.RandomState(12) gmm = GaussianMixture(n_components=self.td.K, num_feat_full=self.td.P, num_feat_comp=self.td.Q, num_feat_shared=self.td.Qs, num_samp=self.td.N, transform=self.td.transform, D_indices=self.td.D_indices, mask=self.td.mask, means_init=None, init_params='random', random_state=random_state) gmm.fit_sparsifier(X=self.td.X) means_init_shape_test = gmm._initialize_means().shape means_init_shape_true = np.array([self.td.K, self.td.P]) self.assertArrayEqual(means_init_shape_test, means_init_shape_true)
def test__initialize_covariances_case3(self): """ No covariances given, just check shape. """ random_state = np.random.RandomState(12) means_init_true = random_state.rand(self.td.K, self.td.P) gmm = GaussianMixture(n_components=self.td.K, num_feat_full=self.td.P, num_feat_comp=self.td.Q, num_feat_shared=self.td.Qs, num_samp=self.td.N, transform=self.td.transform, D_indices=self.td.D_indices, mask=self.td.mask, means_init=means_init_true, covariances_init=None, covariance_type='diag', random_state=random_state) gmm.fit_sparsifier(X=self.td.X) means_init = gmm._initialize_means() covariances_init_test = gmm._initialize_covariances(means_init) true_shape = np.array((self.td.K, self.td.P)) self.assertArrayEqual(covariances_init_test.shape, true_shape)
def test__initialize_covariances_case1(self): """ spherical covariance, 1 init. """ random_state = np.random.RandomState(12) means_init_true = random_state.rand(self.td.K, self.td.P) covariances_init_true = random_state.rand(self.td.K) gmm = GaussianMixture(n_components=self.td.K, num_feat_full=self.td.P, num_feat_comp=self.td.Q, num_feat_shared=self.td.Qs, num_samp=self.td.N, transform=self.td.transform, D_indices=self.td.D_indices, mask=self.td.mask, means_init=means_init_true, covariances_init=covariances_init_true, covariance_type='spherical', random_state=random_state) gmm.fit_sparsifier(X=self.td.X) means_init = gmm._initialize_means() covariances_init_test = gmm._initialize_covariances(means_init) self.assertArrayEqual(covariances_init_test, covariances_init_true)
def test__estimate_log_prob_resp_spherical_shared_compression(self): rs = np.random.RandomState(11) cov_type = 'spherical' gmm = GaussianMixture(n_components=3, num_feat_full=5, num_feat_comp=3, num_feat_shared=3, num_samp=4, transform=None, mask=None, D_indices=None, covariance_type=cov_type, random_state=rs) gmm.fit_sparsifier(X=self.td.X) means = rs.rand(gmm.n_components, gmm.num_feat_full) covariances = rs.rand(gmm.n_components) weights = rs.rand(gmm.n_components) weights /= weights.sum() log_prob_test, log_resp_test, log_prob_norm_test = gmm._estimate_log_prob_resp( weights, means, covariances, cov_type) # find skl's values, pretty ugly to do. precisions = _compute_precision_cholesky(covariances, cov_type) gmm_skl = GMSKL(n_components=3, covariance_type=cov_type) # we need the mask to be shared so that we can use mask[0] on all means gmm_skl.means_ = means[:, gmm.mask[0]] gmm_skl.precisions_cholesky_ = precisions gmm_skl.weights_ = weights gmm_skl.covariance_type_ = cov_type log_prob_norm_true, log_resp_true = gmm_skl._estimate_log_prob_resp( gmm.RHDX) # if anything is bad later this overwrite with mean seems suspect: log_prob_norm_true = log_prob_norm_true.mean() # now get the log_prob from another function log_prob_true = _estimate_log_gaussian_prob(gmm.RHDX, gmm_skl.means_, precisions, cov_type) # run the tests self.assertArrayEqual(log_prob_test, log_prob_true) self.assertArrayEqual(log_prob_norm_true, log_prob_norm_test) self.assertArrayEqual(log_resp_true, log_resp_test)
def test__compute_log_prob_diagonal_no_compression(self): """ Compare the log_prob computation to that of sklearn with no compression. Implemented as a precursor to testing it with compression, to follow. Diagonal covariances. """ cov_type = 'diag' gmm = GaussianMixture(n_components=3, num_feat_full=5, num_feat_comp=5, num_feat_shared=5, num_samp=4, transform=None, mask=None, D_indices=None, covariance_type=cov_type) gmm.fit_sparsifier(X=self.td.X) means = np.random.rand(gmm.n_components, gmm.num_feat_comp) covariances = np.random.rand(gmm.n_components, gmm.num_feat_comp) log_prob_test = gmm._compute_log_prob(means, covariances, cov_type) precisions = _compute_precision_cholesky(covariances, cov_type) log_prob_true = _estimate_log_gaussian_prob(self.td.X, means, precisions, cov_type) self.assertArrayEqual(log_prob_test, log_prob_true)
def test__initialize_means_case2(self): """ means_init is a 3D array. """ random_state = np.random.RandomState(12) n_init = 3 means_init_true = random_state.rand(n_init, self.td.K, self.td.P) gmm = GaussianMixture(n_components=self.td.K, num_feat_full=self.td.P, num_feat_comp=self.td.Q, num_feat_shared=self.td.Qs, num_samp=self.td.N, transform=self.td.transform, D_indices=self.td.D_indices, mask=self.td.mask, means_init=means_init_true, n_init=n_init, random_state=random_state) gmm.fit_sparsifier(X=self.td.X) # first one is discarded for this test _ = gmm._initialize_means() # this should recover the second one means_init_test = gmm._initialize_means() self.assertArrayEqual(means_init_test, means_init_true[1])
def test__compute_logdet_array_spherical(self): """ Test spherical logdet under compression on an example computed here. Redundant with test__compute_logdet_array below but was implemented to confirm that test is correct. """ cov_type = 'spherical' rs = np.random.RandomState(10) gmm = GaussianMixture(n_components=3, num_feat_full=5, num_feat_comp=3, num_feat_shared=2, num_samp=4, transform=None, mask=None, D_indices=None, covariance_type=cov_type, random_state=rs) gmm.fit_sparsifier(X=self.td.X) means = rs.rand(gmm.n_components, gmm.num_feat_full) covariances = rs.rand(gmm.n_components) logdet_test = gmm._compute_logdet_array(covariances, 'spherical') logdet_true = gmm.num_feat_comp * np.log(covariances) logdet_true = np.tile(logdet_true, (gmm.num_samp, 1)) self.assertArrayEqual(logdet_test, logdet_true)
def test__estimate_log_prob_resp_diagonal_no_compression(self): cov_type = 'diag' gmm = GaussianMixture(n_components=3, num_feat_full=5, num_feat_comp=5, num_feat_shared=5, num_samp=4, transform=None, mask=None, D_indices=None, covariance_type=cov_type) gmm.fit_sparsifier(X=self.td.X) means = np.random.rand(gmm.n_components, gmm.num_feat_comp) covariances = np.random.rand(gmm.n_components, gmm.num_feat_comp) weights = np.random.rand(gmm.n_components) weights /= weights.sum() log_prob_test, log_resp_test, log_prob_norm_test = gmm._estimate_log_prob_resp( weights, means, covariances, cov_type) # find skl's values, pretty ugly to do. precisions = _compute_precision_cholesky(covariances, cov_type) gmm_skl = GMSKL(n_components=3, covariance_type=cov_type) gmm_skl.means_ = means gmm_skl.precisions_cholesky_ = precisions gmm_skl.weights_ = weights gmm_skl.covariance_type_ = cov_type log_prob_norm_true, log_resp_true = gmm_skl._estimate_log_prob_resp( self.td.X) # if anything is bad later this overwrite with mean seems suspect: log_prob_norm_true = log_prob_norm_true.mean() # now get the log_prob from another function log_prob_true = _estimate_log_gaussian_prob(self.td.X, means, precisions, cov_type) # run the tests self.assertArrayEqual(log_prob_test, log_prob_true) self.assertArrayEqual(log_prob_norm_true, log_prob_norm_test) self.assertArrayEqual(log_resp_true, log_resp_test)