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arXiv · 1801.04782

Block-coordinate primal-dual method for the nonsmooth minimization over linear constraints

D. Russell Luke·Yura Malitsky
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Abstract

We consider the problem of minimizing a convex, separable, nonsmooth function subject to linear constraints. The numerical method we propose is a block-coordinate extension of the Chambolle-Pock primal-dual algorithm. We prove convergence of the method without resorting to assumptions like smoothness or strong convexity of the objective, full-rank condition on the matrix, strong duality or even consistency of the linear system. Freedom from imposing the latter assumption permits convergence guarantees for misspecified or noisy systems.

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D. Russell Luke, Yura Malitsky. 2018-01-15. Block-coordinate primal-dual method for the nonsmooth minimization over linear constraints. https://doi.org/10.1007/978-3-319-97478-1_6

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