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From: adam <adam.attarian@gmail.com>
Newsgroups: comp.soft-sys.matlab
Subject: Question on evaluating polynomials/polyval
Date: Tue, 16 Jun 2009 12:09:14 -0700 (PDT)
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So the main method that is used by programs/computers to evaluate
polynomials is Horner's Method. That's cool...but i was reading
polyval.m, Matlab's polynomial evaluator, and noticed:

% Make it scream for scalar x.  Polynomial evaluation can be
% implemented as a recursive digital filter.
y = filter(1,[1 -x],p);
y = y(nc);

Here x is the point of evaluation and p is a vector of polynomial
coefficients. I've tried to work out the filter equation and see how
poly evaluation is a filter, but I don't see it. Can anyone help?

Thanks!