skglm.penalties.L0_5¶
- class skglm.penalties.L0_5(alpha)[source]¶
`ell_(0.5)` non-convex quasi-norm penalty.
Methods
__init__
(alpha)derivative
(w)Compute the element-wise derivative.
generalized_support
(w)Return a mask with non-zero coefficients.
get_spec
()Specify the numba types of the class attributes.
is_penalized
(n_features)Return a binary mask with the penalized features.
params_to_dict
()Get the parameters to initialize an instance of the class.
prox_1d
(value, stepsize, j)Compute the proximal operator of L0_5.
prox_vec
(x, stepsize)subdiff_distance
(w, grad, ws)Compute distance of negative gradient to the subdifferential at w.
value
(w)Compute the value of L0_5 at w.