Approximating weak Chebyshev subspaces by Chebyshev subspaces

AbstractWe 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

Approximating Weak Chebyshev Subspaces by Chebyshev Subspaces

We examine to what extent nite-dimensional spaces de ned 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