pyproximal.L0Ball

class pyproximal.L0Ball(radius)

L0 ball proximal operator.

Proximal operator of the L0 ball: \(L0_{r} = \{ \mathbf{x}: ||\mathbf{x}||_0 \leq r \}\).

Parameters

radiusint or func, optional

Radius. This can be a constant number or a function that is called passing a counter which keeps track of how many times the prox method has been invoked before and returns a scalar radius to be used. Radius

Notes

As the L0 ball is an indicator function, the proximal operator corresponds to its orthogonal projection (see pyproximal.projection.L0BallProj for details.

Methods

__init__(radius)
affine_addition(v)	Affine addition
chain(g)	Chain
grad(x)	Compute gradient
postcomposition(sigma)	Postcomposition
precomposition(a, b)	Precomposition
prox(*args, **kwargs)
proxdual(**kwargs)