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On Constrained L2-Approximation of Complex Functions

Published online by Cambridge University Press:  20 November 2018

M. A. Bokhari
M. A. Bokhari*
Affiliation:
Department of Mathematical Sciences, King Fahd University of Petroleum and Minerals, Dhahran 31261 Saudi Arabia, e-mail:FACL049@SAUPM00.BITNET
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Abstract

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A function f analytic in any disc of radius greater than 1 is approximated in the L2-sense over a class of polynomials which also interpolate f on a subset of the roots of unity. The resulting solution is used to discuss Walsh-type equiconvergence. The main theorem of the paper generalizes certain results of Walsh, Rivlin and Cavaretta et al.

Keywords

30E1041A20Taylor's polynomialLagrange interpolantl2 and L2 minimizationinner product spaceequiconvergence
Type
Research Article
Information
Canadian Mathematical Bulletin , Volume 38 , Issue 2 , 01 June 1995 , pp. 149 - 155
Copyright
Copyright © Canadian Mathematical Society 1995

References

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