## Lagrange polynomials

Friday, September 25th, 2009

I read a very nice article in the latest IEEE Signal Processing Magazine: Prandoni, P. and Vetterli, M., “From Lagrange to Shannon… and back: another look at sampling,” IEEE Signal Processing Magazine 26(5):138-144, September 2009. The authors make a case for teaching signal processing starting with discrete time, and then moving to continuous time. I don’t agree, but they expose their case very nicely. But I did learn something new from this paper, which is why I am writing this. It turns out that the Lagrange interpolation polynomials converge to the sinc function as the polynomial order goes to infinity.