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arXiv · 2510.15481

Rational methods for abstract linear initial boundary value problems without order reduction

Carlos Arranz-Simón·Begoña Cano·César Palencia
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Abstract

Given an $A$-stable rational approximation to $e^z$ of order $p$, numerical procedures are suggested to time integrate abstract, well-posed IBVPs, with time-dependent source term $f$ and boundary value $g$. These procedures exhibit the optimal order $p$ and can be implemented by using just one single evaluation of $f$ and $g$ per step, i.e., no evaluations of the derivatives of data are needed, and are of practical use at least for $p\le 6$. The full discretization is also studied and the theoretical results are corroborated by numerical experiments.

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Carlos Arranz-Simón, Begoña Cano, César Palencia. 2025-10-17. Rational methods for abstract linear initial boundary value problems without order reduction. https://arxiv.org/abs/2510.15481

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