Abstract
The method for constructing the Chebyshev approximation of multivariable functions by a logarithmic expression with an absolute error is proposed. It implies constructing an intermediate Chebyshev approximation of the values of the exponent of an approximated function by a polynomial with the relative error. The construction of the Chebyshev approximation by a polynomial is based on calculating the boundary mean-power approximation by an iterative scheme based on the least squares method with properly formed values of variable weight function. The presented results of test examples’ solving confirm the fast convergence of the method in calculating the parameters of the Chebyshev approximation of the functions of one, two, and three variables by the logarithmic expression.
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Translated from Kibernetyka ta Systemnyi Analiz, No. 2, March–April, 2023, pp. 158–165.
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Malachivskyy, P.S., Melnychok, L.S. & Pizyur, Y.V. Chebyshev Approximation of Multivariable Functions by a Logarithmic Expression. Cybern Syst Anal 59, 317–324 (2023). https://doi.org/10.1007/s10559-023-00565-3
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DOI: https://doi.org/10.1007/s10559-023-00565-3