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arXiv · 2102.11079

An Optimal Algorithm for Strongly Convex Minimization under Affine Constraints

Adil Salim·Laurent Condat·Dmitry Kovalev·Peter Richtárik
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Abstract

Optimization problems under affine constraints appear in various areas of machine learning. We consider the task of minimizing a smooth strongly convex function F(x) under the affine constraint Kx=b, with an oracle providing evaluations of the gradient of F and multiplications by K and its transpose. We provide lower bounds on the number of gradient computations and matrix multiplications to achieve a given accuracy. Then we propose an accelerated primal-dual algorithm achieving these lower bounds. Our algorithm is the first optimal algorithm for this class of problems.

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Adil Salim, Laurent Condat, Dmitry Kovalev, Peter Richtárik. 2021-02-22. An Optimal Algorithm for Strongly Convex Minimization under Affine Constraints. https://arxiv.org/abs/2102.11079

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