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arXiv · 2206.11373

How to project onto the intersection of a closed affine subspace and a hyperplane

Heinz H. Bauschke·Dayou Mao·Walaa M. Moursi
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Abstract

Let $A$ be a closed affine subspace and let $B$ be a hyperplane in a Hilbert space. Suppose we are given their associated nearest point mappings $P_A$ and $P_B$, respectively. We present a formula for the projection onto their intersection $A\cap B$. As a special case, we derive a formula for the projection onto the intersection of two hyperplanes. These formulas provides useful information even if $A\cap B$ is empty. Examples and numerical experiments are also provided.

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Heinz H. Bauschke, Dayou Mao, Walaa M. Moursi. 2022-06-22. How to project onto the intersection of a closed affine subspace and a hyperplane. https://arxiv.org/abs/2206.11373

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