Abstract
A method for constructing the Chebyshev approximation of multivariable functions by an exponential expression with a relative error is proposed. It generates an intermediate Chebyshev approximation of the values of the logarithm of a function by a polynomial with the absolute error. An iterative scheme based on the least squares method with a variable weight function is used to construct the Chebyshev approximation of the multivariable functions by a generalized polynomial. The results of solution of the test examples confirm the fast convergence of the method in calculating the parameters of the Chebyshev approximation of the tabular continuous functions of one, two, and three variables.
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Translated from Kibernetyka ta Systemnyi Analiz, No. 3, May–June, 2021, pp. 106–113.
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Malachivskyy, P.S., Melnychok, L.S. & Pizyur, Y.V. Chebyshev Approximation of Multivariable Functions by the Exponential Expression. Cybern Syst Anal 57, 429–435 (2021). https://doi.org/10.1007/s10559-021-00367-5
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DOI: https://doi.org/10.1007/s10559-021-00367-5