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Optimization of Parameters in the Generalized D’alembert Formula for a Function of Two Variables

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Abstract

The authors consider classes of functions that can be exactly reconstructed using the D’Alembert formula generalized by O. M. Lytvyn in 1989. This formula as a special case is known to yield the Taylor polynomial of the expansion of functions in one variable but, unlike the Taylor polynomial, it retains the same differentiability class to which the approximated function belongs, even if its partial derivatives of sth order (s = 1, 2, N) do not belong to the same differentiability class. In such case, the system of parametersβ1, β0, βN is used. The authors propose a method for the optimal choice of these parameters and provide and prove several theorems related to classes of functions that can be exactly reconstructed by the generalized D’Alembert operators.

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References

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Correspondence to I. V. Sergienko.

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Translated from Kibernetyka ta Systemnyi Analiz, No. 4, July–August, 2021, pp. 20–29.

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Sergienko, I.V., Lytvyn, O.M., Lytvyn, O.O. et al. Optimization of Parameters in the Generalized D’alembert Formula for a Function of Two Variables. Cybern Syst Anal 57, 521–529 (2021). https://doi.org/10.1007/s10559-021-00377-3

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  • DOI: https://doi.org/10.1007/s10559-021-00377-3

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