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Projection-free accelerated method for convex optimization. (English) Zbl 1501.90067

Summary: In this paper, we propose a projection-free accelerated method for solving convex optimization problems with unbounded feasible set. The method is an accelerated gradient scheme such that each projection subproblem is approximately solved by means of a conditional gradient scheme. Under reasonable assumptions, it is shown that an \(\varepsilon \)-approximate solution (concept related to the optimal value of the problem) is obtained in at most \((\mathcal{O}(1/\sqrt{\varepsilon})\) gradient evaluations and \(\mathcal{O}(1/\varepsilon)\) linear oracle calls. We also discuss a notion of approximate solution based on the first-order optimality condition of the problem and present iteration-complexity results for the proposed method to obtain an approximate solution in this sense. Finally, numerical experiments illustrating the practical behaviour of the proposed scheme are discussed.

MSC:

90C25 Convex programming
90C06 Large-scale problems in mathematical programming
90C22 Semidefinite programming
49M37 Numerical methods based on nonlinear programming
Full Text: DOI

References:

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