Nearly Coconvex Approximation
Serdica Mathematical Journal, Tome 28 (2002) no. 4, pp. 361-378
Cet article a éte moissonné depuis la source Bulgarian Digital Mathematics Library
Let f ∈ C[−1, 1] change its convexity finitely many times, in the
interval. We are interested in estimating the degree of approximation of f by
polynomials, and by piecewise polynomials, which are nearly coconvex with
it, namely, polynomials and piecewise polynomials that preserve the convexity
of f except perhaps in some small neighborhoods of the points where f
changes its convexity. We obtain Jackson type estimates and summarize the
positive and negative results in a truth-table as we have previously done for
nearly comonotone approximation.
Keywords:
Nearly Coconvex Approximation, Polynomial Approximation, Piecewise Polynomial Approximation, Jackson Estimates
@article{SMJ2_2002_28_4_a6,
author = {Leviatan, D. and Shevchuk, I.},
title = {Nearly {Coconvex} {Approximation}},
journal = {Serdica Mathematical Journal},
pages = {361--378},
year = {2002},
volume = {28},
number = {4},
language = {en},
url = {http://geodesic.mathdoc.fr/item/SMJ2_2002_28_4_a6/}
}
Leviatan, D.; Shevchuk, I. Nearly Coconvex Approximation. Serdica Mathematical Journal, Tome 28 (2002) no. 4, pp. 361-378. http://geodesic.mathdoc.fr/item/SMJ2_2002_28_4_a6/