skglm.penalties.WeightedGroupL2#
- class skglm.penalties.WeightedGroupL2(alpha, weights, grp_ptr, grp_indices)[source]#
Weighted Group L2 penalty.
The penalty reads
`sum_{g=1}^{n_"groups"} "weights"_g xx ||w_{[g]}||`with `w_{[g]}` being the coefficients of the g-th group.
- Attributes:
- alphafloat
The regularization parameter.
- weightsarray, shape (n_groups,)
The weights of the groups.
- grp_indicesarray, shape (n_features,)
The group indices stacked contiguously ([grp1_indices, grp2_indices, …]).
- grp_ptrarray, shape (n_groups + 1,)
The group pointers such that two consecutive elements delimit the indices of a group in
grp_indices
.
Methods
__init__
(alpha, weights, grp_ptr, grp_indices)generalized_support
(w)Return a mask which is True for coefficients in the generalized support.
get_spec
()Specify the numba types of the class attributes.
is_penalized
(n_groups)Return a binary mask with the penalized features.
params_to_dict
()Get the parameters to initialize an instance of the class.
prox_1group
(value, stepsize, g)Compute the proximal operator of group
g
.subdiff_distance
(w, grad_ws, ws)Compute distance to the subdifferential at
w
of negative gradient.value
(w)Value of penalty at vector
w
.