Subject: Problem with expand in lagrange interpolation
From: Daniel Lakeland
Date: Thu, 14 Jun 2007 09:22:58 -0700
On Thu, Jun 14, 2007 at 08:53:52AM -0700, Richard Fateman wrote:
> I think you are doomed if you require that the result is a polynomial in
> expanded form.
> It doesn't matter how you compute the coefficients if you are doing it using
> floating point arithmetic.
Indeed, I was planning to return an *unexpanded* polynomial. In that
case, the particular form of the polynomial essentially encodes the
sequence of operations... it would look like
a(x-x1)(x-x2) + b(x-x1) + c
expanding it will of course eliminate the value of organizing the
computation along these lines, but having a symbolic expression to
carry around is more convenient for various purposes than a block
expression.
--
Daniel Lakeland
dlakelan at street-artists.org
http://www.street-artists.org/~dlakelan