Best approximation in metric spaces

• Autorzy: Narang T. D. , Gupta S.

Identyfikatory

DOI

10.1515/fascmath-2017-0008

• Języki publikacji: EN

Abstrakty

EN

The aim of this paper is to prove some results on the existence and uniqueness of elements of best approximation and continuity of the metric projection in metric spaces. For a subset M of a metric space (X, d), the nature of set of those points of X which have at most one best approximation in M has been discussed. Some equivalent conditions under which an M-space is strictly convex have also been given in this paper.

Słowa kluczowe

EN

proximal set; Chebyshev set; strongly approximately compact set; boundedly compact set; strictly convex metric space

• Wydawca: Wydawnictwo Politechniki Poznańskiej
• Czasopismo: Fasciculi Mathematici
• Rocznik: 2017
• Tom: Nr 58
• Strony: 113--121
• Opis fizyczny: Bibliogr. 15 poz.

Twórcy

autor

Narang T. D.

• Department of Mathematics, Guru Nanak Dev University, Amritsar-143005, India

autor

Gupta S.

• Department of Mathematics, Guru Nanak Dev University, Amritsar-143005, India

Bibliografia

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• [9] Narang T.D., Gupta S., Proximinality and coproximinality in metric linear spaces, Ann. Univ. Mariae Curie-Sklodowska Sect. A, 69(1)(2015), 83-90.
• [10] Narang T.D., Gupta S., On best approximation and best coapproximation, Thai J. Math., 14(2016), 505-516.
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Uwagi

Opracowanie ze środków MNiSW w ramach umowy 812/P-DUN/2016 na działalność upowszechniającą naukę (zadania 2017).