School of Mathematical and Statistical Sciences

Computational and Applied Math Proseminar

Tuesday, February 23, 12:00 p.m. ECG 317

Rodrigo Platte

School of Math&Stats

Impossibility of Approximating Analytic Functions from Equispaced Samples at Geometric Convergence Rates

Abstract How fast can one recover an analytic function from equally spaced samples? For periodic functions, for instance, one can obtain geometric convergence rates as the number of samples is increased using Fourier expansion. In general however, we show that such fast rates are not possible without compromising stability. More specifically, it is shown that no stable procedure for approximating functions from equally spaced samples can converge geometrically for analytic functions.

This work is in collaboration with L.N. Trefethen and A.B. Kuijlaars.