Chebyshev approximation of functions of two variables by a rational expression with interpolation

Fìz.-mat. model. ìnf. tehnol. 2021, 33:33-39

Abstract

A method for constructing a Chebyshev approximation by a rational expression with interpolation for functions of two variables is proposed The idea of the method is based on the construction of the ultimate mean-power approximation in the norm of space L^p at p° . An iterative scheme based on the least squares method with two variable weight functions was used to construct such a Chebyshev approximation. The results of test examples confirm the effectiveness of the proposed method for constructing the Chebyshev approximation by a rational expression with interpolation.

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