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arXiv · 1811.11420

On circumcenter mappings induced by nonexpansive operators

Heinz H. Bauschke·Hui Ouyang·Xianfu Wang
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Abstract

We introduce the circumcenter mapping induced by a set of (usually nonexpansive) operators. One prominent example of a circumcenter mapping is the celebrated Douglas--Rachford splitting operator. Our study is motivated by the Circumcentered--Douglas--Rachford method recently introduced by Behling, Bello Cruz, and Santos in order to accelerate the Douglas--Rachford method for solving certain classes of feasibility problems. We systematically explore the properness of the circumcenter mapping induced by reflectors or projectors. Numerous examples are presented. We also present a version of Browder's demiclosedness principle for circumcenter mappings.

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Heinz H. Bauschke, Hui Ouyang, Xianfu Wang. 2018-11-28. On circumcenter mappings induced by nonexpansive operators. https://arxiv.org/abs/1811.11420

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