Python sklearn.svm.OneClassSVM() Examples

def __init__(self, kernel='rbf', nu=0.1, hybrid=False):
        """Init OCSVM instance."""
        self.kernel = kernel
        self.nu = nu
        self.rho = None
        self.gamma = None

        self.model = OneClassSVM(kernel=kernel, nu=nu)

        self.hybrid = hybrid
        self.ae_net = None  # autoencoder network for the case of a hybrid model
        self.linear_model = None  # also init a model with linear kernel if hybrid approach

        self.results = {
            'train_time': None,
            'test_time': None,
            'test_auc': None,
            'test_scores': None,
            'train_time_linear': None,
            'test_time_linear': None,
            'test_auc_linear': None
        } 

def train_with_scikit(self, trainX, testX):
        settings = self.settings

        if (settings['load_parameters'] == True):
            parameters = self.load_parameters()
            clf = svm.OneClassSVM(parameters)
        else:
            clf = svm.OneClassSVM(nu=settings['nu'], kernel=settings['kernel'], gamma=settings['gamma'], verbose=settings['verbose'])

        clf.fit(trainX)
        y_pred_train = clf.predict(trainX)
        y_pred_test = clf.predict(testX)

        n_error_train = y_pred_train[y_pred_train == -1].size
        n_error_test = y_pred_test[y_pred_test == -1].size

        return y_pred_train, y_pred_test, n_error_train, n_error_test 

def _fit(self, X):
        self.estimator_  = OneClassSVM(
            cache_size   = self.cache_size,
            gamma        = self.gamma,
            max_iter     = self.max_iter,
            nu           = self.nu,
            shrinking    = self.shrinking,
            tol          = self.tol
        ).fit(X)

        l,               = self.support_.shape
        self.nu_l_       = self.nu * l

        Q                = rbf_kernel(
            self.support_vectors_, gamma=self.estimator_._gamma
        )
        c2               = (self.dual_coef_ @ Q @ self.dual_coef_.T)[0, 0]
        self.R2_         = c2 + 2. * self.intercept_[0] + 1.

        return self 

def get_dist(data_list, method):
    Xnumpy = np.asarray(data_list)
    X = Xnumpy.reshape(-1, 1)
    dist = None
    if method == "raw":
        dist = data_list  # raw column data
    if method == "kd":
        kde = KernelDensity(
            kernel=C.kd["kernel"],
            bandwidth=C.kd["bandwidth"]
        ).fit(X)
        dist = kde.score_samples(X)
    elif method == "odsvm":
        svmachine = svm.OneClassSVM(
            nu=C.odsvm["nu"],
            kernel=C.odsvm["kernel"],
            gamma=C.odsvm["gamma"]
        )
        dist = svmachine.fit(X)
    return dist 

def learn_structure(self, samples):
        X_train, X_test = self._generate_train_test_sets(samples, 0.75)
        logger.info("Training with " + str(len(X_train)) +
                    "samples; testing with " + str(len(X_test)) + " samples.")
        svm_detector = svm.OneClassSVM(nu=0.95 * OUTLIERS_FRACTION + 0.05,
                                       kernel="rbf", gamma=0.1)
        svm_detector.fit(X_train)
        Y_test = svm_detector.predict(X_test)
        num_anomalies = Y_test[Y_test == -1].size
        logger.info("Found " + str(num_anomalies) +
                    " anomalies in testing set")
        return svm_detector 

def test_learn_structure(self):
        data = self.get_testing_data()
        clf = self.svm.learn_structure(data)
        self.assertIsInstance(clf, svm.OneClassSVM) 

def check_svm_model_equal(dense_svm, sparse_svm, X_train, y_train, X_test):
    dense_svm.fit(X_train.toarray(), y_train)
    if sparse.isspmatrix(X_test):
        X_test_dense = X_test.toarray()
    else:
        X_test_dense = X_test
    sparse_svm.fit(X_train, y_train)
    assert sparse.issparse(sparse_svm.support_vectors_)
    assert sparse.issparse(sparse_svm.dual_coef_)
    assert_array_almost_equal(dense_svm.support_vectors_,
                              sparse_svm.support_vectors_.toarray())
    assert_array_almost_equal(dense_svm.dual_coef_,
                              sparse_svm.dual_coef_.toarray())
    if dense_svm.kernel == "linear":
        assert sparse.issparse(sparse_svm.coef_)
        assert_array_almost_equal(dense_svm.coef_, sparse_svm.coef_.toarray())
    assert_array_almost_equal(dense_svm.support_, sparse_svm.support_)
    assert_array_almost_equal(dense_svm.predict(X_test_dense),
                              sparse_svm.predict(X_test))
    assert_array_almost_equal(dense_svm.decision_function(X_test_dense),
                              sparse_svm.decision_function(X_test))
    assert_array_almost_equal(dense_svm.decision_function(X_test_dense),
                              sparse_svm.decision_function(X_test_dense))
    if isinstance(dense_svm, svm.OneClassSVM):
        msg = "cannot use sparse input in 'OneClassSVM' trained on dense data"
    else:
        assert_array_almost_equal(dense_svm.predict_proba(X_test_dense),
                                  sparse_svm.predict_proba(X_test), 4)
        msg = "cannot use sparse input in 'SVC' trained on dense data"
    if sparse.isspmatrix(X_test):
        assert_raise_message(ValueError, msg, dense_svm.predict, X_test) 

def test_sparse_oneclasssvm(datasets_index, kernel):
    # Check that sparse OneClassSVM gives the same result as dense OneClassSVM
    # many class dataset:
    X_blobs, _ = make_blobs(n_samples=100, centers=10, random_state=0)
    X_blobs = sparse.csr_matrix(X_blobs)
    datasets = [[X_sp, None, T], [X2_sp, None, T2],
                [X_blobs[:80], None, X_blobs[80:]],
                [iris.data, None, iris.data]]
    dataset = datasets[datasets_index]
    clf = svm.OneClassSVM(gamma=1, kernel=kernel)
    sp_clf = svm.OneClassSVM(gamma=1, kernel=kernel)
    check_svm_model_equal(clf, sp_clf, *dataset) 

def test_oneclass():
    # Test OneClassSVM
    clf = svm.OneClassSVM(gamma='scale')
    clf.fit(X)
    pred = clf.predict(T)

    assert_array_equal(pred, [1, -1, -1])
    assert_equal(pred.dtype, np.dtype('intp'))
    assert_array_almost_equal(clf.intercept_, [-1.218], decimal=3)
    assert_array_almost_equal(clf.dual_coef_,
                              [[0.750, 0.750, 0.750, 0.750]],
                              decimal=3)
    assert_raises(AttributeError, lambda: clf.coef_) 

def test_oneclass_decision_function():
    # Test OneClassSVM decision function
    clf = svm.OneClassSVM()
    rnd = check_random_state(2)

    # Generate train data
    X = 0.3 * rnd.randn(100, 2)
    X_train = np.r_[X + 2, X - 2]

    # Generate some regular novel observations
    X = 0.3 * rnd.randn(20, 2)
    X_test = np.r_[X + 2, X - 2]
    # Generate some abnormal novel observations
    X_outliers = rnd.uniform(low=-4, high=4, size=(20, 2))

    # fit the model
    clf = svm.OneClassSVM(nu=0.1, kernel="rbf", gamma=0.1)
    clf.fit(X_train)

    # predict things
    y_pred_test = clf.predict(X_test)
    assert_greater(np.mean(y_pred_test == 1), .9)
    y_pred_outliers = clf.predict(X_outliers)
    assert_greater(np.mean(y_pred_outliers == -1), .9)
    dec_func_test = clf.decision_function(X_test)
    assert_array_equal((dec_func_test > 0).ravel(), y_pred_test == 1)
    dec_func_outliers = clf.decision_function(X_outliers)
    assert_array_equal((dec_func_outliers > 0).ravel(), y_pred_outliers == 1) 

def test_oneclass_score_samples():
    X_train = [[1, 1], [1, 2], [2, 1]]
    clf = svm.OneClassSVM(gamma=1).fit(X_train)
    assert_array_equal(clf.score_samples([[2., 2.]]),
                       clf.decision_function([[2., 2.]]) + clf.offset_) 

def main2():
	"""
	Use one class SVM for multi-class classification
	
	Accuracy = 71.45%
	"""
	
	# Initializations
	seed = 123456789
	np.random.seed(seed)
	ntrain, ntest = 800, 200
	(tr_x, tr_y), (te_x, te_y) = load_mnist()
	tr, te = [], []
	for i in xrange(10):
		tr.append(np.random.permutation(tr_x[tr_y == i])[:ntrain])
		te.append(np.random.permutation(te_x[te_y == i])[:ntest])
	
	# Train the classifiers and get their results
	clfs = []
	for i in xrange(10):
		clf = OneClassSVM(kernel='linear', nu=0.1, random_state=seed)
		clf.fit(tr[i])
		clfs.append(clf)
		
	# Test the classifiers
	te_x = np.vstack(te)
	te_y = np.hstack([np.array([i] * ntest) for i in xrange(10)])
	results = np.zeros((10, len(te_y)))
	for i in xrange(10):
		results[i] = clfs[i].decision_function(te_x).flatten() + \
			np.random.uniform(0.1, 0.2, len(te_y))
	print np.sum(np.argmax(results, 0) == te_y) / float(len(te_y)) 

def test_36_one_class_svm(self):
        print("\ntest 36 (One Class SVM\n")
        detection_map = {
            'true': -1,
            'false': 1
        }
        df = pd.read_csv("nyoka/tests/train_ocsvm.csv")
        df_test = pd.read_csv("nyoka/tests/test_ocsvm.csv")
        features = df.columns
        model = OneClassSVM(nu=0.1)
        pipeline_obj = Pipeline([
            ("model", model)
        ])
        pipeline_obj.fit(df)
        file_name = 'test36sklearn.pmml'
        skl_to_pmml(pipeline_obj, features, '', file_name)
        model_pred = pipeline_obj.predict(df_test)
        model_scores = pipeline_obj.decision_function(df_test)
        model_name  = self.adapa_utility.upload_to_zserver(file_name)
        z_predictions = self.adapa_utility.score_in_zserver(model_name,'nyoka/tests/test_ocsvm.csv','ANOMALY')
        cnt = 0
        for idx, value in enumerate(z_predictions):
            score, is_anomaly = value.split(",")
            score = float(score)
            if "{:.6f}".format(score) != "{:.6f}".format(model_scores[idx]) or model_pred[idx] != detection_map[is_anomaly]:
                cnt += 1
        self.assertEqual(cnt,0) 

def test_validate_ocsvm(self):
        iris = datasets.load_iris()
        X = iris.data
        y = iris.target
        features = iris.feature_names
        model = OneClassSVM()
        pipeline = Pipeline([
            ('standard_scaler',StandardScaler()),
            ('Imputer',Imputer()),
            ('model',model)
        ])
        pipeline.fit(X,y)
        file_name = model.__class__.__name__+'.pmml'
        skl_to_pmml(pipeline, features ,pmml_f_name= file_name)
        self.assertEqual(self.schema.is_valid(file_name), True) 

def test_sklearn_27(self):
        irisdata = datasets.load_iris()
        iris = pd.DataFrame(irisdata.data, columns=irisdata.feature_names)
        iris['Species'] = irisdata.target

        feature_names = iris.columns.drop('Species')

        X = iris[iris.columns.drop(['Species'])]
        model = OneClassSVM(gamma=0.25)
        pipeline_obj = Pipeline([
            ('standard_scaler', StandardScaler()),
            ('Imputer', Imputer()),
            ('model', model)
        ])

        pipeline_obj.fit(X)
        skl_to_pmml(pipeline_obj, feature_names, pmml_f_name="one_class_svm.pmml")
        pmml_obj = pml.parse("one_class_svm.pmml", True)

        # 1
        self.assertEqual(os.path.isfile("one_class_svm.pmml"), True)

        # 2
        svm_tab = pmml_obj.AnomalyDetectionModel[0].SupportVectorMachineModel
        self.assertEqual(model.gamma, svm_tab.RadialBasisKernelType.gamma)

        # 3
        self.assertEqual(model.intercept_[0], svm_tab.SupportVectorMachine[0].Coefficients.absoluteValue)

        # 4
        for model_val, pmml_val in zip(model.dual_coef_[0], svm_tab.SupportVectorMachine[0].Coefficients.Coefficient):
            self.assertEqual("{:.16f}".format(model_val), "{:.16f}".format(pmml_val.value)) 

def sample_hyps_svm(kern, nu_, deg, shrink):
    """
    :return: A OneClassSVM object with randomly sampled hyperparams, used to detect anomaly.
    """

    kernel = kern #random.choice(['rbf', 'linear', 'poly', 'sigmoid', 'precomputed'])
    nu = nu_ #randrange_float(0.0, 0.9999, 0.05)
    degree = deg #random.randint(1,10)
    gamma = 'auto'  # default. uses 1/n_features
    coef0 = 0.0  # default. No suggested values given in documentation
    shrinking = shrink #random.choice([True, False])

    model = OneClassSVM(kernel=kernel, nu=nu,
                        degree=degree, gamma=gamma,
                        coef0=coef0, shrinking=True)

    resultsfile = open('model_OneClassSVM' +
                       '__kernel_' + str(kernel) +
                       '__nu_' + str(nu) +
                       '__degree_' + str(degree) +
                       '__gamma_' + str(gamma) +
                       '__coef0_' + str(coef0) +
                       '__shrinking_' + str(shrinking),
                       'w')

    return model 

def fit(self):
        print("fit the model")
        train = np.array(self.model.data)
        X = train[:, 0:2]
        y = train[:, 2]

        C = float(self.complexity.get())
        gamma = float(self.gamma.get())
        coef0 = float(self.coef0.get())
        degree = int(self.degree.get())
        kernel_map = {0: "linear", 1: "rbf", 2: "poly"}
        if len(np.unique(y)) == 1:
            clf = svm.OneClassSVM(kernel=kernel_map[self.kernel.get()],
                                  gamma=gamma, coef0=coef0, degree=degree)
            clf.fit(X)
        else:
            clf = svm.SVC(kernel=kernel_map[self.kernel.get()], C=C,
                          gamma=gamma, coef0=coef0, degree=degree)
            clf.fit(X, y)
        if hasattr(clf, 'score'):
            print("Accuracy:", clf.score(X, y) * 100)
        X1, X2, Z = self.decision_surface(clf)
        self.model.clf = clf
        self.model.set_surface((X1, X2, Z))
        self.model.surface_type = self.surface_type.get()
        self.fitted = True
        self.model.changed("surface") 

def init(self):
        self._clf = svm.OneClassSVM(nu=self._nu, kernel="rbf", gamma=self._gamma) 

def _train_ocsvm_and_score(params, xtrain, test_labels, xtest):
    return roc_auc_score(test_labels, OneClassSVM(**params).fit(xtrain).decision_function(xtest)) 

def _raw_ocsvm_experiment(dataset_load_fn, dataset_name, single_class_ind):
    (x_train, y_train), (x_test, y_test) = dataset_load_fn()

    x_train = x_train.reshape((len(x_train), -1))
    x_test = x_test.reshape((len(x_test), -1))

    x_train_task = x_train[y_train.flatten() == single_class_ind]
    if dataset_name in ['cats-vs-dogs']:  # OC-SVM is quadratic on the number of examples, so subsample training set
        subsample_inds = np.random.choice(len(x_train_task), 5000, replace=False)
        x_train_task = x_train_task[subsample_inds]

    pg = ParameterGrid({'nu': np.linspace(0.1, 0.9, num=9),
                        'gamma': np.logspace(-7, 2, num=10, base=2)})

    results = Parallel(n_jobs=6)(
        delayed(_train_ocsvm_and_score)(d, x_train_task, y_test.flatten() == single_class_ind, x_test)
        for d in pg)

    best_params, best_auc_score = max(zip(pg, results), key=lambda t: t[-1])
    best_ocsvm = OneClassSVM(**best_params).fit(x_train_task)
    scores = best_ocsvm.decision_function(x_test)
    labels = y_test.flatten() == single_class_ind

    res_file_name = '{}_raw-oc-svm_{}_{}.npz'.format(dataset_name,
                                                     get_class_name_from_index(single_class_ind, dataset_name),
                                                     datetime.now().strftime('%Y-%m-%d-%H%M'))
    res_file_path = os.path.join(RESULTS_DIR, dataset_name, res_file_name)
    save_roc_pr_curve_data(scores, labels, res_file_path) 

def test_convert_oneclasssvm(self):
        model, X = self._fit_one_class_svm(OneClassSVM())
        model_onnx = convert_sklearn(
            model, "OCSVM", [("input", FloatTensorType([None, X.shape[1]]))])
        dump_data_and_model(
            X,
            model,
            model_onnx,
            basename="SklearnBinOneClassSVM",
            allow_failure="StrictVersion(onnxruntime.__version__)"
                          " < StrictVersion('0.5.0')") 

def initialize_svm(self, loss, **kwargs):

        assert loss in ('SVC', 'OneClassSVM')

        if self.kernel in ('linear', 'poly', 'rbf', 'sigmoid'):
            kernel = self.kernel
        else:
            kernel = 'precomputed'

        if loss == 'SVC':
            self.svm = svm.SVC(kernel=kernel, C=Cfg.svm_C, **kwargs)
        if loss == 'OneClassSVM':
            self.svm = svm.OneClassSVM(kernel=kernel, nu=Cfg.svm_nu, **kwargs)
            self.cv_svm = svm.OneClassSVM(kernel=kernel, nu=Cfg.svm_nu, **kwargs) 

def test_objectmapper(self):
        df = pdml.ModelFrame([])
        self.assertIs(df.svm.SVC, svm.SVC)
        self.assertIs(df.svm.LinearSVC, svm.LinearSVC)
        self.assertIs(df.svm.NuSVC, svm.NuSVC)
        self.assertIs(df.svm.SVR, svm.SVR)
        self.assertIs(df.svm.NuSVR, svm.NuSVR)
        self.assertIs(df.svm.OneClassSVM, svm.OneClassSVM) 

def check_svm_model_equal(dense_svm, sparse_svm, X_train, y_train, X_test):
    dense_svm.fit(X_train.toarray(), y_train)
    if sparse.isspmatrix(X_test):
        X_test_dense = X_test.toarray()
    else:
        X_test_dense = X_test
    sparse_svm.fit(X_train, y_train)
    assert_true(sparse.issparse(sparse_svm.support_vectors_))
    assert_true(sparse.issparse(sparse_svm.dual_coef_))
    assert_array_almost_equal(dense_svm.support_vectors_,
                              sparse_svm.support_vectors_.toarray())
    assert_array_almost_equal(dense_svm.dual_coef_, sparse_svm.dual_coef_.toarray())
    if dense_svm.kernel == "linear":
        assert_true(sparse.issparse(sparse_svm.coef_))
        assert_array_almost_equal(dense_svm.coef_, sparse_svm.coef_.toarray())
    assert_array_almost_equal(dense_svm.support_, sparse_svm.support_)
    assert_array_almost_equal(dense_svm.predict(X_test_dense), sparse_svm.predict(X_test))
    assert_array_almost_equal(dense_svm.decision_function(X_test_dense),
                              sparse_svm.decision_function(X_test))
    assert_array_almost_equal(dense_svm.decision_function(X_test_dense),
                              sparse_svm.decision_function(X_test_dense))
    if isinstance(dense_svm, svm.OneClassSVM):
        msg = "cannot use sparse input in 'OneClassSVM' trained on dense data"
    else:
        assert_array_almost_equal(dense_svm.predict_proba(X_test_dense),
                                  sparse_svm.predict_proba(X_test), 4)
        msg = "cannot use sparse input in 'SVC' trained on dense data"
    if sparse.isspmatrix(X_test):
        assert_raise_message(ValueError, msg, dense_svm.predict, X_test) 

def test_sparse_oneclasssvm():
    """Check that sparse OneClassSVM gives the same result as dense OneClassSVM"""
    # many class dataset:
    X_blobs, _ = make_blobs(n_samples=100, centers=10, random_state=0)
    X_blobs = sparse.csr_matrix(X_blobs)

    datasets = [[X_sp, None, T], [X2_sp, None, T2],
                [X_blobs[:80], None, X_blobs[80:]],
                [iris.data, None, iris.data]]
    kernels = ["linear", "poly", "rbf", "sigmoid"]
    for dataset in datasets:
        for kernel in kernels:
            clf = svm.OneClassSVM(kernel=kernel, random_state=0)
            sp_clf = svm.OneClassSVM(kernel=kernel, random_state=0)
            check_svm_model_equal(clf, sp_clf, *dataset) 

def test_oneclass():
    # Test OneClassSVM
    clf = svm.OneClassSVM()
    clf.fit(X)
    pred = clf.predict(T)

    assert_array_equal(pred, [-1, -1, -1])
    assert_equal(pred.dtype, np.dtype('intp'))
    assert_array_almost_equal(clf.intercept_, [-1.008], decimal=3)
    assert_array_almost_equal(clf.dual_coef_,
                              [[0.632, 0.233, 0.633, 0.234, 0.632, 0.633]],
                              decimal=3)
    assert_raises(AttributeError, lambda: clf.coef_) 

def test_oneclass_decision_function():
    # Test OneClassSVM decision function
    clf = svm.OneClassSVM()
    rnd = check_random_state(2)

    # Generate train data
    X = 0.3 * rnd.randn(100, 2)
    X_train = np.r_[X + 2, X - 2]

    # Generate some regular novel observations
    X = 0.3 * rnd.randn(20, 2)
    X_test = np.r_[X + 2, X - 2]
    # Generate some abnormal novel observations
    X_outliers = rnd.uniform(low=-4, high=4, size=(20, 2))

    # fit the model
    clf = svm.OneClassSVM(nu=0.1, kernel="rbf", gamma=0.1)
    clf.fit(X_train)

    # predict things
    y_pred_test = clf.predict(X_test)
    assert_greater(np.mean(y_pred_test == 1), .9)
    y_pred_outliers = clf.predict(X_outliers)
    assert_greater(np.mean(y_pred_outliers == -1), .9)
    dec_func_test = clf.decision_function(X_test)
    assert_array_equal((dec_func_test > 0).ravel(), y_pred_test == 1)
    dec_func_outliers = clf.decision_function(X_outliers)
    assert_array_equal((dec_func_outliers > 0).ravel(), y_pred_outliers == 1) 

def test_immutable_coef_property():
    # Check that primal coef modification are not silently ignored
    svms = [
        svm.SVC(kernel='linear').fit(iris.data, iris.target),
        svm.NuSVC(kernel='linear').fit(iris.data, iris.target),
        svm.SVR(kernel='linear').fit(iris.data, iris.target),
        svm.NuSVR(kernel='linear').fit(iris.data, iris.target),
        svm.OneClassSVM(kernel='linear').fit(iris.data),
    ]
    for clf in svms:
        assert_raises(AttributeError, clf.__setattr__, 'coef_', np.arange(3))
        assert_raises((RuntimeError, ValueError),
                      clf.coef_.__setitem__, (0, 0), 0) 

def fit(self, X, y=None, sample_weight=None, **params):
        """Fit detector. y is ignored in unsupervised methods.

        Parameters
        ----------
        X : numpy array of shape (n_samples, n_features)
            The input samples.

        y : Ignored
            Not used, present for API consistency by convention.

        sample_weight : array-like, shape (n_samples,)
            Per-sample weights. Rescale C per sample. Higher weights
            force the classifier to put more emphasis on these points.

        Returns
        -------
        self : object
            Fitted estimator.
        """
        # validate inputs X and y (optional)
        X = check_array(X)
        self._set_n_classes(y)

        self.detector_ = OneClassSVM(kernel=self.kernel,
                                     degree=self.degree,
                                     gamma=self.gamma,
                                     coef0=self.coef0,
                                     tol=self.tol,
                                     nu=self.nu,
                                     shrinking=self.shrinking,
                                     cache_size=self.cache_size,
                                     verbose=self.verbose,
                                     max_iter=self.max_iter)
        self.detector_.fit(X=X, y=y, sample_weight=sample_weight,
                           **params)

        # invert decision_scores_. Outliers comes with higher outlier scores
        self.decision_scores_ = invert_order(
            self.detector_.decision_function(X))
        self._process_decision_scores()
        return self 

def _cae_ocsvm_experiment(dataset_load_fn, dataset_name, single_class_ind, gpu_q):
    gpu_to_use = gpu_q.get()
    os.environ["CUDA_VISIBLE_DEVICES"] = gpu_to_use

    (x_train, y_train), (x_test, y_test) = dataset_load_fn()

    n_channels = x_train.shape[get_channels_axis()]
    input_side = x_train.shape[2]  # channel side will always be at shape[2]
    enc = conv_encoder(input_side, n_channels)
    dec = conv_decoder(input_side, n_channels)
    x_in = Input(shape=x_train.shape[1:])
    x_rec = dec(enc(x_in))
    cae = Model(x_in, x_rec)
    cae.compile('adam', 'mse')

    x_train_task = x_train[y_train.flatten() == single_class_ind]
    x_test_task = x_test[y_test.flatten() == single_class_ind]  # This is just for visual monitoring
    cae.fit(x=x_train_task, y=x_train_task, batch_size=128, epochs=200, validation_data=(x_test_task, x_test_task))

    x_train_task_rep = enc.predict(x_train_task, batch_size=128)
    if dataset_name in ['cats-vs-dogs']:  # OC-SVM is quadratic on the number of examples, so subsample training set
        subsample_inds = np.random.choice(len(x_train_task_rep), 2500, replace=False)
        x_train_task_rep = x_train_task_rep[subsample_inds]

    x_test_rep = enc.predict(x_test, batch_size=128)
    pg = ParameterGrid({'nu': np.linspace(0.1, 0.9, num=9),
                        'gamma': np.logspace(-7, 2, num=10, base=2)})

    results = Parallel(n_jobs=6)(
        delayed(_train_ocsvm_and_score)(d, x_train_task_rep, y_test.flatten() == single_class_ind, x_test_rep)
        for d in pg)

    best_params, best_auc_score = max(zip(pg, results), key=lambda t: t[-1])
    print(best_params)
    best_ocsvm = OneClassSVM(**best_params).fit(x_train_task_rep)
    scores = best_ocsvm.decision_function(x_test_rep)
    labels = y_test.flatten() == single_class_ind

    res_file_name = '{}_cae-oc-svm_{}_{}.npz'.format(dataset_name,
                                                     get_class_name_from_index(single_class_ind, dataset_name),
                                                     datetime.now().strftime('%Y-%m-%d-%H%M'))
    res_file_path = os.path.join(RESULTS_DIR, dataset_name, res_file_name)
    save_roc_pr_curve_data(scores, labels, res_file_path)

    gpu_q.put(gpu_to_use)