Continuous selection from the sets of best and near-best approximation
- Authors: Tsar’kov I.G.1
-
Affiliations:
- Mechanics and Mathematics Faculty
- Issue: Vol 96, No 1 (2017)
- Pages: 362-364
- Section: Mathematics
- URL: https://journals.rcsi.science/1064-5624/article/view/225252
- DOI: https://doi.org/10.1134/S1064562417040196
- ID: 225252
Cite item
Abstract
The paper studies approximation and structural geometric-topological properties of sets in normed and more general (asymmetric) spaces for which there exists a continuous selection for the best and near-best approximation operators. Sufficient conditions on the metric projection of sets which ensure the existence of a continuous selection for this projection are obtained, and the structural properties of such sets are determined. The existence of a continuous selection for the near-best approximation operator on a finite-dimensional space more general than a normed space is investigated. It is shown that the lower semicontinuity of the metric projection is sufficient for the existence of a continuous selection for the near-best approximation operator in the general case.
About the authors
I. G. Tsar’kov
Mechanics and Mathematics Faculty
Author for correspondence.
Email: tsar@mech.math.msu.su
Russian Federation, Moscow, 119991