package sklearn
Module Kernels.RationalQuadraticSource
val create :
?length_scale:float ->
?alpha:float ->
?length_scale_bounds:Py.Object.t ->
?alpha_bounds:Py.Object.t ->
unit ->
tRational Quadratic kernel.
The RationalQuadratic kernel can be seen as a scale mixture (an infinite sum) of RBF kernels with different characteristic length-scales. It is parameterized by a length-scale parameter length_scale>0 and a scale mixture parameter alpha>0. Only the isotropic variant where length_scale is a scalar is supported at the moment. The kernel given by:
k(x_i, x_j) = (1 + d(x_i, x_j)^2 / (2*alpha * length_scale^2))^-alpha
.. versionadded:: 0.18
Parameters ---------- length_scale : float > 0, default: 1.0 The length scale of the kernel.
alpha : float > 0, default: 1.0 Scale mixture parameter
length_scale_bounds : pair of floats >= 0, default: (1e-5, 1e5) The lower and upper bound on length_scale
alpha_bounds : pair of floats >= 0, default: (1e-5, 1e5) The lower and upper bound on alpha
Returns a clone of self with given hyperparameters theta.
Parameters ---------- theta : array, shape (n_dims,) The hyperparameters
Returns the diagonal of the kernel k(X, X).
The result of this method is identical to np.diag(self(X)); however, it can be evaluated more efficiently since only the diagonal is evaluated.
Parameters ---------- X : sequence of length n_samples Left argument of the returned kernel k(X, Y)
Returns ------- K_diag : array, shape (n_samples_X,) Diagonal of kernel k(X, X)
Get parameters of this kernel.
Parameters ---------- deep : boolean, optional 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.
Returns whether the kernel is stationary.
Set the parameters of this kernel.
The method works on simple kernels as well as on nested kernels. The latter have parameters of the form ``<component>__<parameter>`` so that it's possible to update each component of a nested object.
Returns ------- self
Pretty-print the object to a formatter.