Alternating forward–backward splitting for linearly constrained optimization problems


We present an alternating forward–backward splitting method for solving linearly constrained structured optimization problems. The algorithm takes advantage of the separable structure and possibly asymmetric regularity properties of the objective functions involved. We also describe some applications to the study of non-Newtonian fluids and image reconstruction problems. We conclude with a numerical example, and its comparison with Condat’s algorithm. An acceleration heuristic is also briefly outlined.

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    This quantity is finite, in view of Proposition 9, and the fact that \((\lambda _n)\in \ell ^2\) [an upper bound can be obtained from (22)].


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Supported by Fondecyt Grant 1181179 and Basal Project CMM Universidad de Chile. The first author was also supported by CONICYT-PCHA/Doctorado Nacional/2016 scholarship.

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Correspondence to Juan Peypouquet.

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Molinari, C., Peypouquet, J. & Roldan, F. Alternating forward–backward splitting for linearly constrained optimization problems. Optim Lett 14, 1071–1088 (2020).

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  • Convex optimization
  • Forward–backward splitting
  • Structured problems