Abstract:
In the present note we will investigate the problem of the one-sided approximation of functions by n-dimensional subspaces. In particular, we will find the exact value of the best one-sided approximation of the class WrL1 (r=1,2,…) of all periodic functions f(x) of period 2π for which f(r−1)(x) (f(0)(x)=f(x)) is absolutely continuous and ‖f(r)‖L1⩽1 by periodic spline functions S2n,μ (μ=0,1,…, n=1,2,…) of period 2π, order μ, and deficiency 1.
Citation:
V. G. Doronin, A. A. Ligun, “Upper bounds for the best one-sided approximation by splines of the classes WrL1”, Mat. Zametki, 19:1 (1976), 11–17; Math. Notes, 19:1 (1976), 7–10
\Bibitem{DorLig76}
\by V.~G.~Doronin, A.~A.~Ligun
\paper Upper bounds for the best one-sided approximation by splines of the classes $W^rL_1$
\jour Mat. Zametki
\yr 1976
\vol 19
\issue 1
\pages 11--17
\mathnet{http://mi.mathnet.ru/mzm7718}
\mathscinet{http://mathscinet.ams.org/mathscinet-getitem?mr=412680}
\zmath{https://zbmath.org/?q=an:0352.41026|0324.41017}
\transl
\jour Math. Notes
\yr 1976
\vol 19
\issue 1
\pages 7--10
\crossref{https://doi.org/10.1007/BF01147610}
Linking options:
https://www.mathnet.ru/eng/mzm7718
https://www.mathnet.ru/eng/mzm/v19/i1/p11
This publication is cited in the following 3 articles:
Parfinovych V N., “Non-Symmetric Approximations of Functional Classes By Splines on the Real Line”, Carpathian Math. Publ., 13:3, SI (2021), 831–837
Babenko V.F., Parfinovich N.V., “NONSYMMETRIC APPROXIMATIONS OF CLASSES OF PERIODIC FUNCTIONS BY SPLINES OF DEFECT 2 AND JACKSON-TYPE INEQUALITIES”, Ukrainian Math J, 61:11 (2009), 1695–1709
V. A. Popov, Linear Spaces and Approximation / Lineare Räume und Approximation, 1978, 449