𝐿¹-approximation with constraints

Pinkus, Allan; Strauss, Hans

doi:10.1090/S0002-9947-1990-0986698-6

$L^ 1$-approximation with constraints
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Trans. Amer. Math. Soc. 322 (1990), 239-261 Request permission

Abstract:

In this paper we study problems of best ${L^1}$-approximation to continuous functions from finite-dimensional subspaces under a variety of constraints. Included are problems of bounded coefficient approximation, approximation with interpolation, restricted range approximation, and restricted range and derivative approximation. Emphasis is placed on problems of uniqueness.

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Uniqueness of best

approximation from a convex set for continuous functions

2

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