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arXiv · 2112.10119

Explicit multivariate approximations from cell-average data

Sergio Amat·David Levin·Juan Ruiz-Alvarez·Dionisio F. Yáñez
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Abstract

Given gridded cell-average data of a smooth multivariate function, we present a constructive explicit procedure for generating a high-order global approximation of the function. One contribution is the derivation of high order approximations to point-values of the function directly from the cell-average data. The second contribution is the development of univariate B-spline based high order quasi-interpolation operators using cell-average data. Multivariate spline quasi-interpolation approximation operators are obtained by tensor products of the univariate operators.

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Sergio Amat, David Levin, Juan Ruiz-Alvarez, Dionisio F. Yáñez. 2021-12-19. Explicit multivariate approximations from cell-average data. https://arxiv.org/abs/2112.10119

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