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Properties of projections obtained by averaging certain polynomial interpolants

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Part of the Lecture Notes in Mathematics book series (LNM,volume 1287)

Abstract

We describe a way to compute polynomial approximants to analytic functions f(z) in the unit disk by forming the average of m polynomials of degree nāˆ’1, each of which interpolates f(z) at n equidistant points on the unit circle. The paper discusses properties of the projections so defined. Norms of these projections are calculated and the asymptotic behavior is characterized. Furthermore, these averages are used to approximate Laurent sections.

Keywords

  • Unit Circle
  • Average Technique
  • Laurent Series
  • Lebesgue Constant
  • Taylor Coefficient

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Ā© 1987 Springer-Verlag

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Palagallo-Price, J., Price, T.E. (1987). Properties of projections obtained by averaging certain polynomial interpolants. In: Saff, E.B. (eds) Approximation Theory, Tampa. Lecture Notes in Mathematics, vol 1287. Springer, Berlin, Heidelberg. https://doi.org/10.1007/BFb0078902

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  • DOI: https://doi.org/10.1007/BFb0078902

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  • Publisher Name: Springer, Berlin, Heidelberg

  • Print ISBN: 978-3-540-18500-0

  • Online ISBN: 978-3-540-47991-8

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