deepod.models.DeepIsolationForest

class deepod.models.DeepIsolationForest(epochs=100, batch_size=1000, lr=0.001, rep_dim=128, hidden_dims='100,50', act='ReLU', bias=False, n_ensemble=50, n_estimators=6, max_samples=256, n_jobs=1, epoch_steps=-1, prt_steps=10, device='cuda', verbose=2, random_state=42)[source]

Deep Isolation Forest for Anomaly Detection

Parameters:
  • epochs (int) – number of training epochs (Default=100).

  • batch_size (int) – number of samples in a mini-batch (Default=64)

  • lr (float) – it is for consistency, unused in this model

Methods

__init__([epochs, batch_size, lr, rep_dim, ...])

decision_function(X)

Predict raw anomaly scores of X using the fitted detector.

decision_function_update(z, scores)

for any updating operation after decision function

epoch_update()

for any updating operation after each training epoch

fit(X[, y])

Fit detector.

fit_auto_hyper(X[, y, X_test, y_test, ...])

Fit detector.

inference_forward(batch_x, net, criterion)

define forward step in inference

inference_prepare(X)

define test_loader

load_model(path)

load_ray_checkpoint(best_config, best_checkpoint)

predict(X[, return_confidence])

Predict if a particular sample is an outlier or not.

save_model(path)

set_seed(seed)

set_tuned_net(config)

set_tuned_params()

training_forward(batch_x, net, criterion)

define forward step in training

training_prepare(X, y)

define train_loader, net, and criterion

decision_function(X)[source]

Predict raw anomaly scores of X using the fitted detector.

The anomaly score of an input sample is computed based on the fitted detector. For consistency, outliers are assigned with higher anomaly scores.

Parameters:

X (numpy array of shape (n_samples, n_features)) – The input samples. Sparse matrices are accepted only if they are supported by the base estimator.

Returns:

anomaly_scores – The anomaly score of the input samples.

Return type:

numpy array of shape (n_samples,)

decision_function_update(z, scores)

for any updating operation after decision function

epoch_update()

for any updating operation after each training epoch

fit(X, y=None)[source]

Fit detector. y is ignored in unsupervised methods.

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

  • y (numpy array of shape (n_samples, )) – Not used in unsupervised methods, present for API consistency by convention. used in (semi-/weakly-) supervised methods

Returns:

self – Fitted estimator.

Return type:

object

fit_auto_hyper(X, y=None, X_test=None, y_test=None, n_ray_samples=5, time_budget_s=None)

Fit detector. y is ignored in unsupervised methods.

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

  • y (numpy array of shape (n_samples, )) – Not used in unsupervised methods, present for API consistency by convention. used in (semi-/weakly-) supervised methods

  • X_test (numpy array of shape (n_samples, n_features), default=None) – The input testing samples for hyper-parameter tuning.

  • y_test (numpy array of shape (n_samples, ), default=None) – Label of input testing samples for hyper-parameter tuning.

  • n_ray_samples (int, default=5) – Number of times to sample from the hyperparameter space

  • time_budget_s (int, default=None) – Global time budget in seconds after which all trials of Ray are stopped.

Returns:

config – tuned hyper-parameter

Return type:

dict

inference_forward(batch_x, net, criterion)[source]

define forward step in inference

inference_prepare(X)[source]

define test_loader

predict(X, return_confidence=False)

Predict if a particular sample is an outlier or not.

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

  • return_confidence (boolean, optional(default=False)) – If True, also return the confidence of prediction.

Returns:

  • outlier_labels (numpy array of shape (n_samples,)) – For each observation, tells whether it should be considered as an outlier according to the fitted model. 0 stands for inliers and 1 for outliers.

  • confidence (numpy array of shape (n_samples,).) – Only if return_confidence is set to True.

training_forward(batch_x, net, criterion)[source]

define forward step in training

training_prepare(X, y)[source]

define train_loader, net, and criterion