package sklearn

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type tag = [
  1. | `MultiTaskElasticNet
]
type t = [ `BaseEstimator | `MultiOutputMixin | `MultiTaskElasticNet | `Object | `RegressorMixin ] Obj.t
val of_pyobject : Py.Object.t -> t
val to_pyobject : [> tag ] Obj.t -> Py.Object.t
val as_estimator : t -> [ `BaseEstimator ] Obj.t
val as_regressor : t -> [ `RegressorMixin ] Obj.t
val as_multi_output : t -> [ `MultiOutputMixin ] Obj.t
val create : ?alpha:float -> ?l1_ratio:float -> ?fit_intercept:bool -> ?normalize:bool -> ?copy_X:bool -> ?max_iter:int -> ?tol:float -> ?warm_start:bool -> ?random_state:int -> ?selection:[ `Cyclic | `Random ] -> unit -> t

Multi-task ElasticNet model trained with L1/L2 mixed-norm as regularizer

The optimization objective for MultiTaskElasticNet is::

(1 / (2 * n_samples)) * ||Y - XW||_Fro^2

  1. alpha * l1_ratio * ||W||_21
  2. 0.5 * alpha * (1 - l1_ratio) * ||W||_Fro^2

Where::

||W||_21 = sum_i sqrt(sum_j W_ij ^ 2)

i.e. the sum of norms of each row.

Read more in the :ref:`User Guide <multi_task_elastic_net>`.

Parameters ---------- alpha : float, default=1.0 Constant that multiplies the L1/L2 term. Defaults to 1.0

l1_ratio : float, default=0.5 The ElasticNet mixing parameter, with 0 < l1_ratio <= 1. For l1_ratio = 1 the penalty is an L1/L2 penalty. For l1_ratio = 0 it is an L2 penalty. For ``0 < l1_ratio < 1``, the penalty is a combination of L1/L2 and L2.

fit_intercept : bool, default=True 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).

normalize : bool, default=False This parameter is ignored when ``fit_intercept`` is set to False. If True, the regressors X will be normalized before regression by subtracting the mean and dividing by the l2-norm. If you wish to standardize, please use :class:`sklearn.preprocessing.StandardScaler` before calling ``fit`` on an estimator with ``normalize=False``.

copy_X : bool, default=True If ``True``, X will be copied; else, it may be overwritten.

max_iter : int, default=1000 The maximum number of iterations

tol : float, default=1e-4 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``.

warm_start : bool, default=False When set to ``True``, reuse the solution of the previous call to fit as initialization, otherwise, just erase the previous solution. See :term:`the Glossary <warm_start>`.

random_state : int, RandomState instance, default=None 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 :term:`Glossary <random_state>`.

selection : 'cyclic', 'random', default='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.

Attributes ---------- intercept_ : ndarray of shape (n_tasks,) Independent term in decision function.

coef_ : ndarray of shape (n_tasks, n_features) Parameter vector (W in the cost function formula). If a 1D y is passed in at fit (non multi-task usage), ``coef_`` is then a 1D array. Note that ``coef_`` stores the transpose of ``W``, ``W.T``.

n_iter_ : int number of iterations run by the coordinate descent solver to reach the specified tolerance.

Examples -------- >>> from sklearn import linear_model >>> clf = linear_model.MultiTaskElasticNet(alpha=0.1) >>> clf.fit([0,0], [1, 1], [2, 2], [0, 0], [1, 1], [2, 2]) MultiTaskElasticNet(alpha=0.1) >>> print(clf.coef_) [0.45663524 0.45612256] [0.45663524 0.45612256] >>> print(clf.intercept_) 0.0872422 0.0872422

See also -------- MultiTaskElasticNet : Multi-task L1/L2 ElasticNet with built-in cross-validation. ElasticNet MultiTaskLasso

Notes ----- The algorithm used to fit the model is coordinate descent.

To avoid unnecessary memory duplication the X and y arguments of the fit method should be directly passed as Fortran-contiguous numpy arrays.

val fit : x:[> `ArrayLike ] Np.Obj.t -> y:[> `ArrayLike ] Np.Obj.t -> [> tag ] Obj.t -> t

Fit MultiTaskElasticNet model with coordinate descent

Parameters ---------- X : ndarray of shape (n_samples, n_features) Data y : ndarray of shape (n_samples, n_tasks) Target. Will be cast to X's dtype if necessary

Notes -----

Coordinate descent is an algorithm that considers each column of data at a time hence it will automatically convert the X input as a Fortran-contiguous numpy array if necessary.

To avoid memory re-allocation it is advised to allocate the initial data in memory directly using that format.

val get_params : ?deep:bool -> [> tag ] Obj.t -> Dict.t

Get parameters for this estimator.

Parameters ---------- deep : bool, default=True If True, will return the parameters for this estimator and contained subobjects that are estimators.

Returns ------- params : mapping of string to any Parameter names mapped to their values.

val predict : x:[> `ArrayLike ] Np.Obj.t -> [> tag ] Obj.t -> [> `ArrayLike ] Np.Obj.t

Predict using the linear model.

Parameters ---------- X : array_like or sparse matrix, shape (n_samples, n_features) Samples.

Returns ------- C : array, shape (n_samples,) Returns predicted values.

val score : ?sample_weight:[> `ArrayLike ] Np.Obj.t -> x:[> `ArrayLike ] Np.Obj.t -> y:[> `ArrayLike ] Np.Obj.t -> [> tag ] Obj.t -> float

Return the coefficient of determination R^2 of the prediction.

The coefficient R^2 is defined as (1 - 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.

Parameters ---------- X : array-like of shape (n_samples, n_features) Test samples. For some estimators this may be a precomputed kernel matrix or a list of generic objects instead, shape = (n_samples, n_samples_fitted), where n_samples_fitted is the number of samples used in the fitting for the estimator.

y : array-like of shape (n_samples,) or (n_samples, n_outputs) True values for X.

sample_weight : array-like of shape (n_samples,), default=None Sample weights.

Returns ------- score : float R^2 of self.predict(X) wrt. y.

Notes ----- The R2 score used when calling ``score`` on a regressor uses ``multioutput='uniform_average'`` from version 0.23 to keep consistent with default value of :func:`~sklearn.metrics.r2_score`. This influences the ``score`` method of all the multioutput regressors (except for :class:`~sklearn.multioutput.MultiOutputRegressor`).

val set_params : ?params:(string * Py.Object.t) list -> [> tag ] Obj.t -> t

Set the parameters of this estimator.

The method works on simple estimators as well as on nested objects (such as pipelines). The latter have parameters of the form ``<component>__<parameter>`` so that it's possible to update each component of a nested object.

Parameters ---------- **params : dict Estimator parameters.

Returns ------- self : object Estimator instance.

val intercept_ : t -> [> `ArrayLike ] Np.Obj.t

Attribute intercept_: get value or raise Not_found if None.

val intercept_opt : t -> [> `ArrayLike ] Np.Obj.t option

Attribute intercept_: get value as an option.

val coef_ : t -> [> `ArrayLike ] Np.Obj.t

Attribute coef_: get value or raise Not_found if None.

val coef_opt : t -> [> `ArrayLike ] Np.Obj.t option

Attribute coef_: get value as an option.

val n_iter_ : t -> int

Attribute n_iter_: get value or raise Not_found if None.

val n_iter_opt : t -> int option

Attribute n_iter_: get value as an option.

val to_string : t -> string

Print the object to a human-readable representation.

val show : t -> string

Print the object to a human-readable representation.

val pp : Format.formatter -> t -> unit

Pretty-print the object to a formatter.

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