Volume 31, Issue 6 e2579
RESEARCH ARTICLE

Accurate bidiagonal decompositions of Cauchy–Vandermonde matrices of any rank

Jorge Delgado

Jorge Delgado

Departamento de Matemática Aplicada, Universidad de Zaragoza, Edificio Torres Quevedo, Zaragoza, Spain

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Plamen Koev

Corresponding Author

Plamen Koev

Department of Mathematics, San Jose State University, San Jose, California, USA

Correspondence

Plamen Koev, Department of Mathematics, San Jose State University, San Jose, CA 95192, USA.

Email: [email protected]

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Ana Marco

Ana Marco

Departamento de Física y Matemáticas, Universidad de Alcalá, Alcalá de Henares, Madrid, Spain

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José-Javier Martínez

José-Javier Martínez

Departamento de Física y Matemáticas, Universidad de Alcalá, Alcalá de Henares, Madrid, Spain

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Juan Manuel Peña

Juan Manuel Peña

Departamento de Matemática Aplicada, Universidad de Zaragoza, Edificio de Matemáticas, 50019 Zaragoza, Spain

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Per-Olof Persson

Per-Olof Persson

Department of Mathematics, University of California, Berkeley, California, USA

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Steven Spasov

Steven Spasov

Columbia University, New York, 10027 New York, USA

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First published: 06 August 2024

Abstract

We present a new decomposition of a Cauchy–Vandermonde matrix as a product of bidiagonal matrices which, unlike its existing bidiagonal decompositions, is now valid for a matrix of any rank. The new decompositions are insusceptible to the phenomenon known as subtractive cancellation in floating point arithmetic and are thus computable to high relative accuracy. In turn, other accurate matrix computations are also possible with these matrices, such as eigenvalue computation amongst others.

CONFLICT OF INTEREST STATEMENT

The authors have no conflicts of interest to disclose.

DATA AVAILABILITY STATEMENT

Data sharing is not applicable to this article as no new data were created or analyzed in this study.

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