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arXiv · 2204.05463

Construction of high-order robust theta-methods with applications in anomalous models

Baoli Yin·Guoyu Zhang·Yang Liu·Hong Li
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Abstract

A general conversion strategy by involving a shifted parameter $θ$ is proposed to construct high-order accuracy difference formulas for fractional calculus operators. By converting the second-order backward difference formula with such strategy, a novel $θ$-scheme with correction terms is developed for the subdiffusion problem with nonsmooth data, which is robust even for very small $α$ and can resolve the initial singularity.The optimal error estimates are carried out with essential arguments and are verified by numerical tests.

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Baoli Yin, Guoyu Zhang, Yang Liu, Hong Li. 2022-04-12. Construction of high-order robust theta-methods with applications in anomalous models. https://arxiv.org/abs/2204.05463

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