mrpro.operators.ScaledProximableFunctional

class mrpro.operators.ScaledProximableFunctional(functional: Functional, scale: Tensor | float)[source]

Bases: ScaledFunctional, ProximableFunctional

Proximable Functional scaled by a scalar.

__init__(functional: Functional, scale: Tensor | float) → None

Initialize a scaled functional.

A scaled functional is a functional that is scaled by a scalar factor \(\alpha\), i.e. \(f(x) = \alpha g(x)\).

Parameters:

  • functional – functional to be scaled

  • scale – scaling factor, must be real and positive

forward(x: Tensor) → tuple[Tensor]

Forward method.

Parameters:

x – input tensor

Return type:

scaled output of the functional

prox(x: Tensor, sigma: Tensor | float = 1.0) → tuple[Tensor][source]

Proximal Mapping.

Parameters:

  • x – input tensor

  • sigma – scaling factor

Return type:

Proximal mapping applied to the input tensor

prox_convex_conj(x: Tensor, sigma: Tensor | float = 1.0) → tuple[Tensor][source]

Proximal Mapping of the convex conjugate.

Parameters:

  • x – input tensor

  • sigma – scaling factor

Return type:

Proximal mapping of the convex conjugate applied to the input tensor