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From: "Dmitry Dmitry" <klio2003@list.ru>
Newsgroups: comp.soft-sys.matlab
Subject: Re: nonlinear system of equations
Date: Sat, 8 Mar 2008 19:07:02 +0000 (UTC)
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Tom, thanks for your reply!!!

In fact, I don't know the exact solution, therefore I 
pointed ZERO values as the starting ones. In fact, the 
solution, as I've written, is very close, but still it 
doesn't satisfy the accuracy requirements. Concerning 
Jacobian, I tried both: calculating it myself and making 
FSOLVE do it. The difference doesn't seem much.

At the end of iteration process I saw the warning: 

"Optimizer appears to be converging to a minimum that is 
not a root:
Sum of squares of the function values is > sqrt
(options.TolFun).
Try again with a new starting point."

So the optimizer has found a minimum but not a zero, 
however the criterion (of FSOLVE function) is satisfied!!!

How can I guess the starting point? How can I improve 
FSOLVE work?

Thanks in advance,

Dmitry