On subgradient projectors

Heinz H. Bauschke; Caifang Wang; Xianfu Wang; Jia Xu

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arXiv · 1403.7135

On subgradient projectors

Heinz H. Bauschke·Caifang Wang·Xianfu Wang·Jia Xu

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Abstract

The subgradient projector is of considerable importance in convex optimization because it plays the key role in Polyak's seminal work - and the many papers it spawned - on subgradient projection algorithms for solving convex feasibility problems. In this paper, we offer a systematic study of the subgradient projector. Fundamental properties such as continuity, nonexpansiveness, and monotonicity are investigated. We also discuss the Yamagishi-Yamada operator. Numerous examples illustrate our results.

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BibTeX RIS

Heinz H. Bauschke, Caifang Wang, Xianfu Wang, Jia Xu. 2014-03-27. On subgradient projectors. https://arxiv.org/abs/1403.7135

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