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.