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LassoCV

Lasso linear model with iterative fitting along a regularization path.

See glossary entry for cross-validation estimator.

The best model is selected by cross-validation.

The optimization objective for Lasso is:

Python Reference

Constructors

constructor()

Signature

new LassoCV(opts?: object): LassoCV;

Parameters

Name Type Description
opts? object -
opts.alphas? ArrayLike List of alphas where to compute the models. If undefined alphas are set automatically.
opts.copy_X? boolean If true, X will be copied; else, it may be overwritten. Default Value true
opts.cv? number Determines the cross-validation splitting strategy. Possible inputs for cv are:
opts.eps? number Length of the path. eps=1e-3 means that alpha\_min / alpha\_max \= 1e-3. Default Value 0.001
opts.fit_intercept? boolean Whether to calculate the intercept for this model. If set to false, no intercept will be used in calculations (i.e. data is expected to be centered). Default Value true
opts.max_iter? number The maximum number of iterations. Default Value 1000
opts.n_alphas? number Number of alphas along the regularization path. Default Value 100
opts.n_jobs? number Number of CPUs to use during the cross validation. undefined means 1 unless in a joblib.parallel\_backend context. \-1 means using all processors. See Glossary for more details.
opts.positive? boolean If positive, restrict regression coefficients to be positive. Default Value false
opts.precompute? boolean | ArrayLike[] | "auto" Whether to use a precomputed Gram matrix to speed up calculations. If set to 'auto' let us decide. The Gram matrix can also be passed as argument. Default Value 'auto'
opts.random_state? number The seed of the pseudo random number generator that selects a random feature to update. Used when selection == ‘random’. Pass an int for reproducible output across multiple function calls. See Glossary.
opts.selection? "random" | "cyclic" If set to ‘random’, a random coefficient is updated every iteration rather than looping over features sequentially by default. This (setting to ‘random’) often leads to significantly faster convergence especially when tol is higher than 1e-4. Default Value 'cyclic'
opts.tol? number The tolerance for the optimization: if the updates are smaller than tol, the optimization code checks the dual gap for optimality and continues until it is smaller than tol. Default Value 0.0001
opts.verbose? number | boolean Amount of verbosity. Default Value false

Returns

LassoCV

Defined in: generated/linear_model/LassoCV.ts:27

Methods

dispose()

Disposes of the underlying Python resources.

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

Signature

dispose(): Promise<void>;

Returns

Promise<void>

Defined in: generated/linear_model/LassoCV.ts:188

fit()

Fit linear model with coordinate descent.

Fit is on grid of alphas and best alpha estimated by cross-validation.

Signature

fit(opts: object): Promise<any>;

Parameters

Name Type Description
opts object -
opts.X? ArrayLike Training data. Pass directly as Fortran-contiguous data to avoid unnecessary memory duplication. If y is mono-output, X can be sparse.
opts.sample_weight? number | ArrayLike Sample weights used for fitting and evaluation of the weighted mean squared error of each cv-fold. Note that the cross validated MSE that is finally used to find the best model is the unweighted mean over the (weighted) MSEs of each test fold.
opts.y? ArrayLike Target values.

Returns

Promise<any>

Defined in: generated/linear_model/LassoCV.ts:207

get_metadata_routing()

Get metadata routing of this object.

Please check User Guide on how the routing mechanism works.

Signature

get_metadata_routing(opts: object): Promise<any>;

Parameters

Name Type Description
opts object -
opts.routing? any A MetadataRequest encapsulating routing information.

Returns

Promise<any>

Defined in: generated/linear_model/LassoCV.ts:256

init()

Initializes the underlying Python resources.

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

Signature

init(py: PythonBridge): Promise<void>;

Parameters

Name Type
py PythonBridge

Returns

Promise<void>

Defined in: generated/linear_model/LassoCV.ts:135

path()

Compute Lasso path with coordinate descent.

The Lasso optimization function varies for mono and multi-outputs.

For mono-output tasks it is:

Signature

path(opts: object): Promise<ArrayLike>;

Parameters

Name Type Description
opts object -
opts.X? ArrayLike Training data. Pass directly as Fortran-contiguous data to avoid unnecessary memory duplication. If y is mono-output then X can be sparse.
opts.Xy? ArrayLike Xy = np.dot(X.T, y) that can be precomputed. It is useful only when the Gram matrix is precomputed.
opts.alphas? ArrayLike List of alphas where to compute the models. If undefined alphas are set automatically.
opts.coef_init? ArrayLike The initial values of the coefficients.
opts.copy_X? boolean If true, X will be copied; else, it may be overwritten. Default Value true
opts.eps? number Length of the path. eps=1e-3 means that alpha\_min / alpha\_max \= 1e-3. Default Value 0.001
opts.n_alphas? number Number of alphas along the regularization path. Default Value 100
opts.params? any Keyword arguments passed to the coordinate descent solver.
opts.positive? boolean If set to true, forces coefficients to be positive. (Only allowed when y.ndim \== 1). Default Value false
opts.precompute? boolean | ArrayLike[] | "auto" Whether to use a precomputed Gram matrix to speed up calculations. If set to 'auto' let us decide. The Gram matrix can also be passed as argument. Default Value 'auto'
opts.return_n_iter? boolean Whether to return the number of iterations or not. Default Value false
opts.verbose? number | boolean Amount of verbosity. Default Value false
opts.y? any Target values.

Returns

Promise<ArrayLike>

Defined in: generated/linear_model/LassoCV.ts:293

predict()

Predict using the linear model.

Signature

predict(opts: object): Promise<any>;

Parameters

Name Type Description
opts object -
opts.X? any Samples.

Returns

Promise<any>

Defined in: generated/linear_model/LassoCV.ts:418

score()

Return the coefficient of determination of the prediction.

The coefficient of determination \(R^2\) is defined as \((1 - \frac{u}{v})\), where \(u\) is the residual sum of squares ((y\_true \- y\_pred)\*\* 2).sum() and \(v\) is the total sum of squares ((y\_true \- y\_true.mean()) \*\* 2).sum(). The best possible score is 1.0 and it can be negative (because the model can be arbitrarily worse). A constant model that always predicts the expected value of y, disregarding the input features, would get a \(R^2\) score of 0.0.

Signature

score(opts: object): Promise<number>;

Parameters

Name Type Description
opts object -
opts.X? ArrayLike[] Test samples. For some estimators this may be a precomputed kernel matrix or a list of generic objects instead with shape (n\_samples, n\_samples\_fitted), where n\_samples\_fitted is the number of samples used in the fitting for the estimator.
opts.sample_weight? ArrayLike Sample weights.
opts.y? ArrayLike True values for X.

Returns

Promise<number>

Defined in: generated/linear_model/LassoCV.ts:451

set_fit_request()

Request metadata passed to the fit 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:

Signature

set_fit_request(opts: object): Promise<any>;

Parameters

Name Type Description
opts object -
opts.sample_weight? string | boolean Metadata routing for sample\_weight parameter in fit.

Returns

Promise<any>

Defined in: generated/linear_model/LassoCV.ts:502

set_score_request()

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:

Signature

set_score_request(opts: object): Promise<any>;

Parameters

Name Type Description
opts object -
opts.sample_weight? string | boolean Metadata routing for sample\_weight parameter in score.

Returns

Promise<any>

Defined in: generated/linear_model/LassoCV.ts:539

Properties

_isDisposed

boolean = false

Defined in: generated/linear_model/LassoCV.ts:25

_isInitialized

boolean = false

Defined in: generated/linear_model/LassoCV.ts:24

_py

PythonBridge

Defined in: generated/linear_model/LassoCV.ts:23

id

string

Defined in: generated/linear_model/LassoCV.ts:20

opts

any

Defined in: generated/linear_model/LassoCV.ts:21

Accessors

alpha_

The amount of penalization chosen by cross validation.

Signature

alpha_(): Promise<number>;

Returns

Promise<number>

Defined in: generated/linear_model/LassoCV.ts:572

alphas_

The grid of alphas used for fitting.

Signature

alphas_(): Promise<ArrayLike>;

Returns

Promise<ArrayLike>

Defined in: generated/linear_model/LassoCV.ts:662

coef_

Parameter vector (w in the cost function formula).

Signature

coef_(): Promise<ArrayLike>;

Returns

Promise<ArrayLike>

Defined in: generated/linear_model/LassoCV.ts:594

dual_gap_

The dual gap at the end of the optimization for the optimal alpha (alpha\_).

Signature

dual_gap_(): Promise<number | ArrayLike>;

Returns

Promise<number | ArrayLike>

Defined in: generated/linear_model/LassoCV.ts:685

feature_names_in_

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

Signature

feature_names_in_(): Promise<ArrayLike>;

Returns

Promise<ArrayLike>

Defined in: generated/linear_model/LassoCV.ts:756

intercept_

Independent term in decision function.

Signature

intercept_(): Promise<number | ArrayLike>;

Returns

Promise<number | ArrayLike>

Defined in: generated/linear_model/LassoCV.ts:616

mse_path_

Mean square error for the test set on each fold, varying alpha.

Signature

mse_path_(): Promise<ArrayLike[]>;

Returns

Promise<ArrayLike[]>

Defined in: generated/linear_model/LassoCV.ts:639

n_features_in_

Number of features seen during fit.

Signature

n_features_in_(): Promise<number>;

Returns

Promise<number>

Defined in: generated/linear_model/LassoCV.ts:731

n_iter_

Number of iterations run by the coordinate descent solver to reach the specified tolerance for the optimal alpha.

Signature

n_iter_(): Promise<number>;

Returns

Promise<number>

Defined in: generated/linear_model/LassoCV.ts:708

py

Signature

py(): PythonBridge;

Returns

PythonBridge

Defined in: generated/linear_model/LassoCV.ts:122

Signature

py(pythonBridge: PythonBridge): void;

Parameters

Name Type
pythonBridge PythonBridge

Returns

void

Defined in: generated/linear_model/LassoCV.ts:126