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arXiv · 2403.18017

Nonsingularity of unsymmetric Kansa matrices: random collocation by MultiQuadrics and Inverse MultiQuadrics

R. Cavoretto·F. Dell'Accio·A. De Rossi·A. Sommariva·M. Vianello
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Abstract

Unisolvence of unsymmetric Kansa collocation is still a substantially open problem. We prove that Kansa matrices with MultiQuadrics and Inverse MultiQuadrics for the Dirichlet problem of the Poisson equation are almost surely nonsingular, when the collocation points are chosen by any continuous random distribution in the domain interior and arbitrarily on its boundary.

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R. Cavoretto, F. Dell'Accio, A. De Rossi, A. Sommariva, M. Vianello. 2024-03-26. Nonsingularity of unsymmetric Kansa matrices: random collocation by MultiQuadrics and Inverse MultiQuadrics. https://arxiv.org/abs/2403.18017

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