A Lagrange-type projector on the real line

Mastroianni, G.; Notarangelo, I.

doi:10.1090/S0025-5718-09-02278-9

A Lagrange-type projector on the real line
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by G. Mastroianni and I. Notarangelo PDF

Math. Comp. 79 (2010), 327-352 Request permission

Abstract:

We introduce an interpolation process based on some of the zeros of the $m$th generalized Freud polynomial. Convergence results and error estimates are given. In particular we show that, in some important function spaces, the interpolating polynomial behaves like the best approximation. Moreover the stability and the convergence of some quadrature rules are proved.

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