Abstract
In this paper we consider the problem of best uniform approximation of a real valued semi-Lipschitz function \(F\) defined on an asymmetric metric space \((X,d)\), by the elements of the set \(E_{d}(F|_{Y})\) of all extensions of \(F|_{Y}(Y\subset X)\), preserving the smallest semi-Lipschitz constant. It is proved that, this problem has always at least a solution, if \((X,d)\) is \((d,\overline{d})\)-sequentially compact, or of finite diameter.
Authors
Costică Mustăţa
“Tiberiu Popoviciu” Institute of Numerical Analysis, Romanian Academi, Romania
Keywords
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Paper coordinates
C. Mustăţa, Best uniform approximation of semi-Lipschitz function by extension, Rev. Anal. Numér. Théor. Approx. 36 (2007) 2, pp. 161-171.
About this paper
Journal
Revue d’Analyse Numer. Theor. Approx.
Publisher Name
Publishing House of the Romanian Academy
Print ISSN
2501-059X
Online ISSN
2457-6794
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