On rational interpolation to |x| at the extended Chebyshev nodes

doi:10.3969/j.issn.1000-1565.2023.01.003

Abstract

Abstract: In this paper, the rational interpolation of |x| at the extended Chebyshev nodes was studied. That the exact order of approximation is O(1/(nln n))was obtained. Through numerical calculation, it is found that the error of the same approximation order is related to the density of nodes and the concavity and convexity of the curve where the nodes are located.

Key words: extended Chebyshev nodes, rational interpolation, Newman-type rational operators, order of approximation, error

CLC Number:

O174.41

LI Jianjun, ZHANG Huiming. On rational interpolation to |x| at the extended Chebyshev nodes[J]. Journal of Hebei University(Natural Science Edition), 2023, 43(1): 16-20.

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