DocumentationClassesEllipticEnvelope

Class: EllipticEnvelope

An object for detecting outliers in a Gaussian distributed dataset.

Read more in the User Guide.

Python Reference

Constructors

new EllipticEnvelope()

new EllipticEnvelope(opts?): EllipticEnvelope

Parameters

ParameterTypeDescription
opts?object-
opts.assume_centered?booleanIf true, the support of robust location and covariance estimates is computed, and a covariance estimate is recomputed from it, without centering the data. Useful to work with data whose mean is significantly equal to zero but is not exactly zero. If false, the robust location and covariance are directly computed with the FastMCD algorithm without additional treatment.
opts.contamination?numberThe amount of contamination of the data set, i.e. the proportion of outliers in the data set. Range is (0, 0.5].
opts.random_state?numberDetermines the pseudo random number generator for shuffling the data. Pass an int for reproducible results across multiple function calls. See Glossary.
opts.store_precision?booleanSpecify if the estimated precision is stored.
opts.support_fraction?numberThe proportion of points to be included in the support of the raw MCD estimate. If undefined, the minimum value of support_fraction will be used within the algorithm: (n_samples + n_features + 1) / 2 \* n_samples. Range is (0, 1).

Returns EllipticEnvelope

Defined in generated/covariance/EllipticEnvelope.ts:23

Properties

PropertyTypeDefault valueDefined in
_isDisposedbooleanfalsegenerated/covariance/EllipticEnvelope.ts:21
_isInitializedbooleanfalsegenerated/covariance/EllipticEnvelope.ts:20
_pyPythonBridgeundefinedgenerated/covariance/EllipticEnvelope.ts:19
idstringundefinedgenerated/covariance/EllipticEnvelope.ts:16
optsanyundefinedgenerated/covariance/EllipticEnvelope.ts:17

Accessors

covariance_

Get Signature

get covariance_(): Promise<ArrayLike[]>

Estimated robust covariance matrix.

Returns Promise<ArrayLike[]>

Defined in generated/covariance/EllipticEnvelope.ts:673


dist_

Get Signature

get dist_(): Promise<ArrayLike>

Mahalanobis distances of the training set (on which fit is called) observations.

Returns Promise<ArrayLike>

Defined in generated/covariance/EllipticEnvelope.ts:862


feature_names_in_

Get Signature

get feature_names_in_(): Promise<ArrayLike>

Names of features seen during fit. Defined only when X has feature names that are all strings.

Returns Promise<ArrayLike>

Defined in generated/covariance/EllipticEnvelope.ts:916


location_

Get Signature

get location_(): Promise<ArrayLike>

Estimated robust location.

Returns Promise<ArrayLike>

Defined in generated/covariance/EllipticEnvelope.ts:646


n_features_in_

Get Signature

get n_features_in_(): Promise<number>

Number of features seen during fit.

Returns Promise<number>

Defined in generated/covariance/EllipticEnvelope.ts:889


offset_

Get Signature

get offset_(): Promise<number>

Offset used to define the decision function from the raw scores. We have the relation: decision_function \= score_samples \- offset_. The offset depends on the contamination parameter and is defined in such a way we obtain the expected number of outliers (samples with decision function < 0) in training.

Returns Promise<number>

Defined in generated/covariance/EllipticEnvelope.ts:754


precision_

Get Signature

get precision_(): Promise<ArrayLike[]>

Estimated pseudo inverse matrix. (stored only if store_precision is true)

Returns Promise<ArrayLike[]>

Defined in generated/covariance/EllipticEnvelope.ts:700


py

Get Signature

get py(): PythonBridge

Returns PythonBridge

Set Signature

set py(pythonBridge): void

Parameters

ParameterType
pythonBridgePythonBridge

Returns void

Defined in generated/covariance/EllipticEnvelope.ts:59


raw_covariance_

Get Signature

get raw_covariance_(): Promise<ArrayLike[]>

The raw robust estimated covariance before correction and re-weighting.

Returns Promise<ArrayLike[]>

Defined in generated/covariance/EllipticEnvelope.ts:808


raw_location_

Get Signature

get raw_location_(): Promise<ArrayLike>

The raw robust estimated location before correction and re-weighting.

Returns Promise<ArrayLike>

Defined in generated/covariance/EllipticEnvelope.ts:781


raw_support_

Get Signature

get raw_support_(): Promise<ArrayLike>

A mask of the observations that have been used to compute the raw robust estimates of location and shape, before correction and re-weighting.

Returns Promise<ArrayLike>

Defined in generated/covariance/EllipticEnvelope.ts:835


support_

Get Signature

get support_(): Promise<ArrayLike>

A mask of the observations that have been used to compute the robust estimates of location and shape.

Returns Promise<ArrayLike>

Defined in generated/covariance/EllipticEnvelope.ts:727

Methods

correct_covariance()

correct_covariance(opts): Promise<ArrayLike[]>

Apply a correction to raw Minimum Covariance Determinant estimates.

Correction using the empirical correction factor suggested by Rousseeuw and Van Driessen in [RVD].

Parameters

ParameterTypeDescription
optsobject-
opts.data?ArrayLike[]The data matrix, with p features and n samples. The data set must be the one which was used to compute the raw estimates.

Returns Promise<ArrayLike[]>

Defined in generated/covariance/EllipticEnvelope.ts:132


decision_function()

decision_function(opts): Promise<ArrayLike>

Compute the decision function of the given observations.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLike[]The data matrix.

Returns Promise<ArrayLike>

Defined in generated/covariance/EllipticEnvelope.ts:168


dispose()

dispose(): Promise<void>

Disposes of the underlying Python resources.

Once dispose() is called, the instance is no longer usable.

Returns Promise<void>

Defined in generated/covariance/EllipticEnvelope.ts:113


error_norm()

error_norm(opts): Promise<number>

Compute the Mean Squared Error between two covariance estimators.

Parameters

ParameterTypeDescription
optsobject-
opts.comp_cov?ArrayLike[]The covariance to compare with.
opts.norm?"frobenius" | "spectral"The type of norm used to compute the error. Available error types: - ‘frobenius’ (default): sqrt(tr(A^t.A)) - ‘spectral’: sqrt(max(eigenvalues(A^t.A)) where A is the error (comp_cov \- self.covariance_).
opts.scaling?booleanIf true (default), the squared error norm is divided by n_features. If false, the squared error norm is not rescaled.
opts.squared?booleanWhether to compute the squared error norm or the error norm. If true (default), the squared error norm is returned. If false, the error norm is returned.

Returns Promise<number>

Defined in generated/covariance/EllipticEnvelope.ts:204


fit()

fit(opts): Promise<any>

Fit the EllipticEnvelope model.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLike[]Training data.
opts.y?anyNot used, present for API consistency by convention.

Returns Promise<any>

Defined in generated/covariance/EllipticEnvelope.ts:259


fit_predict()

fit_predict(opts): Promise<ArrayLike>

Perform fit on X and returns labels for X.

Returns -1 for outliers and 1 for inliers.

Parameters

ParameterTypeDescription
optsobject-
opts.kwargs?anyArguments to be passed to fit.
opts.X?ArrayLikeThe input samples.
opts.y?anyNot used, present for API consistency by convention.

Returns Promise<ArrayLike>

Defined in generated/covariance/EllipticEnvelope.ts:300


get_metadata_routing()

get_metadata_routing(opts): Promise<any>

Get metadata routing of this object.

Please check User Guide on how the routing mechanism works.

Parameters

ParameterTypeDescription
optsobject-
opts.routing?anyA MetadataRequest encapsulating routing information.

Returns Promise<any>

Defined in generated/covariance/EllipticEnvelope.ts:346


get_precision()

get_precision(opts): Promise<any>

Getter for the precision matrix.

Parameters

ParameterTypeDescription
optsobject-
opts.precision_?ArrayLike[]The precision matrix associated to the current covariance object.

Returns Promise<any>

Defined in generated/covariance/EllipticEnvelope.ts:382


init()

init(py): Promise<void>

Initializes the underlying Python resources.

This instance is not usable until the Promise returned by init() resolves.

Parameters

ParameterType
pyPythonBridge

Returns Promise<void>

Defined in generated/covariance/EllipticEnvelope.ts:72


mahalanobis()

mahalanobis(opts): Promise<ArrayLike>

Compute the squared Mahalanobis distances of given observations.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLike[]The observations, the Mahalanobis distances of the which we compute. Observations are assumed to be drawn from the same distribution than the data used in fit.

Returns Promise<ArrayLike>

Defined in generated/covariance/EllipticEnvelope.ts:418


predict()

predict(opts): Promise<ArrayLike>

Predict labels (1 inlier, -1 outlier) of X according to fitted model.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLike[]The data matrix.

Returns Promise<ArrayLike>

Defined in generated/covariance/EllipticEnvelope.ts:452


reweight_covariance()

reweight_covariance(opts): Promise<ArrayLike>

Re-weight raw Minimum Covariance Determinant estimates.

Re-weight observations using Rousseeuw’s method (equivalent to deleting outlying observations from the data set before computing location and covariance estimates) described in [RVDriessen].

Parameters

ParameterTypeDescription
optsobject-
opts.data?ArrayLike[]The data matrix, with p features and n samples. The data set must be the one which was used to compute the raw estimates.

Returns Promise<ArrayLike>

Defined in generated/covariance/EllipticEnvelope.ts:488


score()

score(opts): Promise<number>

Return the mean accuracy on the given test data and labels.

In multi-label classification, this is the subset accuracy which is a harsh metric since you require for each sample that each label set be correctly predicted.

Parameters

ParameterTypeDescription
optsobject-
opts.sample_weight?ArrayLikeSample weights.
opts.X?ArrayLike[]Test samples.
opts.y?ArrayLikeTrue labels for X.

Returns Promise<number>

Defined in generated/covariance/EllipticEnvelope.ts:526


score_samples()

score_samples(opts): Promise<ArrayLike>

Compute the negative Mahalanobis distances.

Parameters

ParameterTypeDescription
optsobject-
opts.X?ArrayLike[]The data matrix.

Returns Promise<ArrayLike>

Defined in generated/covariance/EllipticEnvelope.ts:570


set_score_request()

set_score_request(opts): Promise<any>

Request metadata passed to the score method.

Note that this method is only relevant if enable_metadata_routing=True (see sklearn.set_config). Please see User Guide on how the routing mechanism works.

The options for each parameter are:

Parameters

ParameterTypeDescription
optsobject-
opts.sample_weight?string | booleanMetadata routing for sample_weight parameter in score.

Returns Promise<any>

Defined in generated/covariance/EllipticEnvelope.ts:610