From: Alan Weiss <>
Newsgroups: comp.soft-sys.matlab
Subject: Re: Radius of convergence?
Date: Mon, 09 Feb 2009 09:54:23 -0500
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Joerg Buchholz wrote:
> syms x
> f = sin (x)
> t = taylor (f)
> returns the Maclaurin approximation of the sine function. Is there a way to compute the radius of convergence of the approximation analytically?
Hi, I am not sure I understand your question. Radius of convergence 
usually applies to functions whose Taylor series can diverge if more 
terms are taken. It is well known that the radius of convergence of a 
Taylor series for the sine function is infinity.

However, perhaps you are asking if there is a way for the Symbolic Math 
Toolbox to analytically demonstrate that the radius is infinity. Is that 
your question?

Alan Weiss
MATLAB mathematical toolbox documentation