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Efficient implementation of bivariate interpolation and cubature at Padua points

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Efficient implementation of bivariate interpolation and cubature at Padua points

Marco Caliari* and Stefano De Marchi

Department of Computer Science, University of Verona Strada Le Grazie 15, 37134 Verona (ITALY)

Marco Vianello and Alvise Sommariva

Department of Pure and Applied Mathematics, University of Padua Via Trieste 63, 35121 Padova (ITALY)

May 28, 2008

Abstract

A new set of points for polynomial interpolation on the square [−1, 1]

2

, called

“Padua points”, was introduced and experimentally studied. It has been proved that they are unisolvent in the full polynomial space and that they give the first known example of non tensor-product optimal interpolation in two variables, since their Lebesgue constant has minimal order of growth of O((log n)

2

).

In this talk we present a stable and efficient Fortran BLAS-based implemen-

tation and a new Matlab FFT-based implementation of the Lagrange interpo-

lation formula and cubature at the Padua points.

Riferimenti

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