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Trigonometric approximation of functions in seminormed spaces. (English) Zbl 1466.42003

Summary: In this paper, we study the approximation properties of \(2\pi\)-periodic functions in a seminormed space. We use a general matrix method of summability, and the moduli of continuity in the seminormed space as a measure of approximation. Our results generalize and improve some of the previous results available in the literature.

MSC:

42A10 Trigonometric approximation
40C05 Matrix methods for summability
41A25 Rate of convergence, degree of approximation
42A24 Summability and absolute summability of Fourier and trigonometric series
46E30 Spaces of measurable functions (\(L^p\)-spaces, Orlicz spaces, Köthe function spaces, Lorentz spaces, rearrangement invariant spaces, ideal spaces, etc.)
Full Text: DOI

References:

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