Uniform Approximation of Functions of Two Variables

Cybernetics and Systems Analysis volume 53, pages426–431(2017)Cite this article

Abstract

We propose an algorithm to construct a uniform approximation of functions of two variables as a boundary approximation in norm Lp as p → ∞. It is based on root mean square approximation with variable weight function. We propose a technique of successive adjustment of weight function and give examples of uniform approximation of tabulated functions of two variables with the use of the least squares method with variable weight function.

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Author information

Affiliations

  1. Center of Mathematical Modeling, Ya. S. Pidstryhach Institute for Applied Problems of Mechanics and Mathematics, National Academy of Sciences of Ukraine, Lviv, Ukraine

    P. S. Malachivskyy

  2. National University “Lvivska Politekhnika,”, Lviv, Ukraine

    Ya. N. Matviychuk, Ya. V. Pizyur & R. P. Malachivskyi

Authors
  1. P. S. Malachivskyy
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  2. Ya. N. Matviychuk
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  3. Ya. V. Pizyur
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  4. R. P. Malachivskyi
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Corresponding author

Correspondence to P. S. Malachivskyy.

Additional information

Translated from Kibernetika i Sistemnyi Analiz, No. 3, May–June, 2017, pp. 111–116.

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Malachivskyy, P.S., Matviychuk, Y.N., Pizyur, Y.V. et al. Uniform Approximation of Functions of Two Variables. Cybern Syst Anal 53, 426–431 (2017). https://doi.org/10.1007/s10559-017-9943-5

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Keywords

  • uniform approximation
  • function of two variables
  • approximation in the norm of space L p
  • least squares method with variable weight function