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arXiv · 2602.14609

Advances on the recovery of (perturbed) Cauchy matrices

Paola Boito·Dario Fasino·Beatrice Meini
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Abstract

Given a (possibly approximate) Cauchy matrix, how can we efficiently compute its generators? Expanding on previous work by Liesen and Luce [Linear Algebra Appl. 493 (2016) 261--280], we present a general family of algorithms for Cauchy parameter recovery, together with new error estimates. We also introduce a displacement-based approximation, which leads to a new algorithm for Cauchy parameter recovery. Numerical experiments show that the algorithm based on the displacement approximation is generally more accurate than the other algorithms.

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Paola Boito, Dario Fasino, Beatrice Meini. 2026-02-16. Advances on the recovery of (perturbed) Cauchy matrices. https://arxiv.org/abs/2602.14609

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