Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
Optimal Subspaces for Mean Square Approximation of Classes of Differentiable Functions on a Segment. / Vinogradov, O. L.; Ulitskaya, A. Yu.
в: Vestnik St. Petersburg University: Mathematics, Том 53, № 3, 01.07.2020, стр. 270-281.Результаты исследований: Научные публикации в периодических изданиях › статья › Рецензирование
}
TY - JOUR
T1 - Optimal Subspaces for Mean Square Approximation of Classes of Differentiable Functions on a Segment
AU - Vinogradov, O. L.
AU - Ulitskaya, A. Yu
N1 - Funding Information: This work is supported by the Russian Science Foundation under grant no. 18-11-00055. Publisher Copyright: © 2020, Pleiades Publishing, Ltd. Copyright: Copyright 2020 Elsevier B.V., All rights reserved.
PY - 2020/7/1
Y1 - 2020/7/1
N2 - In this paper, a set of optimal subspaces is specified for L-2 approximation of three classes of functions in the Sobolev spaces W-2((r)) defined on a segment and subject to certain boundary conditions. A subspaceXof a dimension not exceedingnis called optimal for a function class A if the best approximation of A by X is equal to the Kolmogorovn-width of A. These boundary conditions correspond to subspaces of periodically extended functions with symmetry properties. All approximating subspaces are generated by equidistant shifts of a single function. The conditions of optimality are given in terms of Fourier coefficients of a generating function. In particular, we indicate optimal spline spaces of all degrees d greater than or similar to r-1 with equidistant knots of several different types.
AB - In this paper, a set of optimal subspaces is specified for L-2 approximation of three classes of functions in the Sobolev spaces W-2((r)) defined on a segment and subject to certain boundary conditions. A subspaceXof a dimension not exceedingnis called optimal for a function class A if the best approximation of A by X is equal to the Kolmogorovn-width of A. These boundary conditions correspond to subspaces of periodically extended functions with symmetry properties. All approximating subspaces are generated by equidistant shifts of a single function. The conditions of optimality are given in terms of Fourier coefficients of a generating function. In particular, we indicate optimal spline spaces of all degrees d greater than or similar to r-1 with equidistant knots of several different types.
KW - n-widths
KW - spaces of shifts
KW - splines
UR - http://www.scopus.com/inward/record.url?scp=85090048492&partnerID=8YFLogxK
U2 - 10.1134/S1063454120030164
DO - 10.1134/S1063454120030164
M3 - Article
AN - SCOPUS:85090048492
VL - 53
SP - 270
EP - 281
JO - Vestnik St. Petersburg University: Mathematics
JF - Vestnik St. Petersburg University: Mathematics
SN - 1063-4541
IS - 3
ER -
ID: 72082167