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arXiv · 2404.16694

A non-separable progressive multivariate WENO-$2r$ point value

Pep Mulet·Juan Ruiz-Alvarez·Chi-Wang Shu·Dionisio F. Yáñez
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Abstract

The weighted essentially non-oscillatory {technique} using a stencil of $2r$ points (WENO-$2r$) is an interpolatory method that consists in obtaining a higher approximation order from the non-linear combination of interpolants of $r+1$ nodes. The result is an interpolant of order $2r$ at the smooth parts and order $r+1$ when an isolated discontinuity falls at any grid interval of the large stencil except at the central one. Recently, a new WENO method based on Aitken-Neville's algorithm has been designed for interpolation of equally spaced data at the mid-points and presents progressive order of accuracy close to discontinuities. This paper is devoted to constructing a general progressive WENO method for non-necessarily uniformly spaced data and several variables interpolating in any point of the central interval. Also, we provide explicit formulas for linear and non-linear weights and prove the order obtained. Finally, some numerical experiments are presented to check the theoretical results.

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Pep Mulet, Juan Ruiz-Alvarez, Chi-Wang Shu, Dionisio F. Yáñez. 2024-04-25. A non-separable progressive multivariate WENO-$2r$ point value. https://arxiv.org/abs/2404.16694

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