Abstract
In the present paper an orthogonal system of Chebyshev–Markov rational fractions is considered. We introduce the corresponding Fourier series and find the Dirichlet integral. We obtain the decomposition of the function |x| into Fourier series with respect to the considered system in explicit form and an asymptotic estimate of the uniform approximation of this function by partial sums of the rational Fourier–Chebyshev series.
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References
H. Akcay and B. Ninness, Rational Basis Functions for Robust Identification from Frequency and Time Domain Measurements, Technical Report EE9718, Department of Electrical and Computer Engineering, University of Newcastle, Australia.
S. Bernstein, Sur meilleure approximation de |x| par des polynômes de degrés donnés, Acta Math., 37 (1913), 1–57.
J. Bokor and F. Schipp, Approximate linear H 1 identification in Laguerre and Kautz basis, IFAC Automatica J., 34 (1998), 463–468.
A. Bultheel, P. Gonzalez-Vera, E. Hendriksen and O. Njastad, Orthogonal Rational Functions, Cambridge University Press (1999).
A. Bultheel, M. Van Barel and P. Van Gucht, Orthogonal basis functions in discrete least-squares rational approximation, J. Comput. Appl. Math., 164-165 (2004), 175–194.
E. W. Cheney and T. J. Rivlin, A note on some Lebesgue constants, Rocky Mountain J. Math., 6 (1976), 435–439.
M. M. Dzhrbashyan, On the theory of Fourier series in terms of rational functions, Izv. Arm. SSR. Ser. Fiz-Mat. Nauk, 9 (1956), 3–28 (in Russian).
M. M. Dzhrbashyan and A. A. Kitbalyan, On a generalization of the Chebyshev polynomials, Akad. Nauk Armjan. SSR Dokl., 38 (1964), 263–270 (in Russian).
V. K. Dzyadyk, An Introduction to the Theory of Uniform Approximation of Functions by Polynomials, Nauka (Moscow, 1977) (in Russian).
M. A. Evgrafov, Asymptotic Estimates and Entire Functions, Gordon and Breach Science Pub. (1962).
M. V. Fedoriuk, Asymptotics. Integrals and Series, Nauka (Moscow, 1987) (in Russian).
I. S. Gradshtein and I. M. Ryzhik, Tables of Integrals, Series and Products, Fizmatlit (Moscow, 1963) (in Russian); translation: Academic Press (New York, London, 1965).
A. A. Kitbalyan, Expansions in generalized trigonometric systems, Izv. Arm. SSR. Ser. Fiz-Mat. Nauk, 16 (1963), 3–24 (in Russian).
G. S. Kocharyan, Approximation of rational fnctions in complex domain, Izv. Arm. SSR. Ser. Fiz-Mat. Nauk, 11 (1958), 53–77 (in Russian).
F. Malmquist, Sur la détermination d’une classe functions analytiques par leurs dans un ensemble donné de points, in: Comptes Rendus Sixiéme Congrés des mathématiciens scandinaves (1925), Gjellerup (Copenhagen, 1925), pp. 253–259.
A. A. Markov, Selected Papers, AN SSSR (1948) (in Russian).
I. P. Natanson, Constructive Function Theory, Ungar (New York, 1964).
D. Newman, Rational approximation to |x|, Michigan Math. J., 11 (1964), 11–14.
M. Pap, Slice regular Malmquist–Takenaka system in the quaternionic Hardy spaces, Anal. Math., 44 (2017), 99–114.
P. P. Petrushev and B. A. Popov, Rational Approximation of Real Functions, Cambridge University Press (1987).
Y. A. Rouba, Interpolation and Fourier Series in the Rational Approximation, GrSU (Grodno, 2001) (in Russian).
E. A. Rovba, An approximation of |sin x| by rational Fourier series, Mat. Zametki, 46 (1989), 52–59; translation in Math. Notes, 46 (1989), 788794.
E. A. Rouba and E. G. Mikulich, Constants in the approximation of the function |x| by rational interpolation processes, Dokl. Nats. Akad. Nauk Belarusi, 53 (2009), 11–15 (in Russian).
V. N. Rusak, Rational Functions as Approximation Apparatus, Izdat. Belorus Gos. Univ. (Minsk, 1979) (in Russian).
H. Stahl, Best uniform rational approximation of |x| on [-1, 1], Mat. Sb., 183 (1992), 85–118; translation in Russian Acad. Sci. Sb. Math., 76 (1993), 461–487.
P. K. Suetin, Classical Orthogonal Polynomials, Fizmatlit (Moscow, 2005) (in Russian).
S. Takenaka, On the orthogonal functions and a new formula of interpolations, Japanese J. Math., 2 (1925), 129–145.
P. Tchébycheff, Sur les questions de minima qui se rattachent à la représentation approximative des fonctions, Mém. Acad. Sci. St. Pétersbourg, 1(5) (1859), 199–291.
N. Vjacheslavov, On the uniform approximation of |x| by rational functions, Dokl. Akad. Nauk SSSR, 220 (1975), 512–515; translated in Soviet Math. Dokl., 16 (1975), 100–104.
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Rouba, Y., Patseika, P. & Smatrytski, K. On a System of Rational Chebyshev–Markov Fractions. Anal Math 44, 115–140 (2018). https://doi.org/10.1007/s10476-018-0110-7
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DOI: https://doi.org/10.1007/s10476-018-0110-7
Key words and phrases
- Chebyshev–Markov rational fraction
- orthogonal system
- Fourier series
- Dirichlet integral
- approximation
- asymptotic estimate
- exact estimate