Best comonotone approximation

Deutsch, Frank; Zhong, Jun

doi:10.1090/S0002-9947-1994-1260201-1

Best comonotone approximation
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by Frank Deutsch and Jun Zhong PDF

Trans. Amer. Math. Soc. 344 (1994), 617-627 Request permission

Abstract:

A general theory of best comonotone approximation in $C[a,b]$ by elements of an n-dimensional extended Chebyshev subspace is described. In particular, theorems on the existence, (in general) nonuniqueness, and characterization of best comonotone approximations are established.

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