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arXiv · 1111.2435

A Simple Algorithm for Constructing all Real Hessenberg Unitary Matrices

Janet C. Tremain
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Abstract

Unitary matrices which are zero below the secondary diagonal (Hessenberg unitary matrices) have many uses in analysis. Given a set of needed conditions on a unitary matrix, this algorithm will give the sparsest unitary matrix. We give an algorithm for constructing all real Hessenberg unitary matrices. The $n\times n$ unitary matrices given by the algorithm have $n-1$ variables which can be chosen to give additional properties needed for a particular application.

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Janet C. Tremain. 2011-11-10. A Simple Algorithm for Constructing all Real Hessenberg Unitary Matrices. https://arxiv.org/abs/1111.2435

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