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Simultaneous Approximation of Sobolev Classes by Piecewise Cubic Hermite Interpolation

Published online by Cambridge University Press:  28 May 2015

Guiqiao Xu*
Affiliation:
Department of Mathematics, Tianjin Normal University, Tianjin, 300387, P.R. China
Zheng Zhang
Affiliation:
Department of Mathematics, Tianjin Normal University, Tianjin, 300387, P.R. China
*
*Corresponding author.Email address:[email protected]
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Abstract

For the approximation in Lp-norm, we determine the weakly asymptotic orders for the simultaneous approximation errors of Sobolev classes by piecewise cubic Hermite interpolation with equidistant knots. For p = 1, ∞, we obtain its values. By these results we know that for the Sobolev classes, the approximation errors by piecewise cubic Hermite interpolation are weakly equivalent to the corresponding infinite-dimensional Kolmogorov widths. At the same time, the approximation errors of derivatives are weakly equivalent to the corresponding infinite-dimensional Kolmogorov widths.

Type
Research Article
Copyright
Copyright © Global Science Press Limited 2014

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