On weak Chebyshev subspaces and Chebyshev approximation by their elements
نویسندگان
چکیده
منابع مشابه
Approximating weak Chebyshev subspaces by Chebyshev subspaces
We examine to what extent finite-dimensional spaces defined on locally compact subsets of the line and possessing various weak Chebyshev properties (involving sign changes, zeros, alternation of best approximations, and peak points) can be uniformly approximated by a sequence of spaces having related properties. r 2003 Elsevier Science (USA). All rights reserved.
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We present two characterizations of Lagrange interpolation sets for weak Chebyshev spaces. The rst of them is valid for an arbitrary weak Chebyshev space U and is based on an analysis of the structure of zero sets of functions in U extending Stockenberg's theorem. The second one holds for all weak Chebyshev spaces that possess a locally linearly independent basis. x1. Introduction Let U denote ...
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ژورنال
عنوان ژورنال: Applicationes Mathematicae
سال: 1979
ISSN: 1233-7234,1730-6280
DOI: 10.4064/am-16-3-475-483