Skip to content

JuliaSmoothOptimizers/ShiftedProximalOperators.jl

Repository files navigation

ShiftedProximalOperators

CI codecov DOI

How to cite

If you use ShiftedProximalOperators.jl in your work, please cite using the format given in CITATION.bib.

Synopsis

ShiftedProximalOperators is a library of proximal operators associated with proper lower-semicontinuous functions such as those implemented in ProximalOperators.jl for use in the algorithms implemented in RegularizedOptimization.jl.

The main difference between the proximal operators implemented in ProximalOperators.jl is that those implemented here involve a translation of the nonsmooth term. Specifically, this package considers proximal operators defined as

argmin { ½ ‖t - q‖₂² + ν h(x + s + t) + χ(s + t; ΔB) | t ∈ ℝⁿ },

where q is given, x and s are fixed shifts, h is the nonsmooth term with respect to which we are computing the proximal operator, and χ(.; ΔB) is the indicator of a ball of radius Δ defined by a certain norm.

How to Install

Until this package is registered, use

pkg> add https://github.com/rjbaraldi/ShiftedProximalOperators.jl

What is Implemented?

Please refer to the documentation.

Related Software

References

  • A. Y. Aravkin, R. Baraldi and D. Orban, A Proximal Quasi-Newton Trust-Region Method for Nonsmooth Regularized Optimization, SIAM Journal on Optimization, 32(2), pp.900–929, 2022. Technical report: https://arxiv.org/abs/2103.15993