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Topic: Problem with "lsqnonlin" function in matlab
Replies: 6   Last Post: Sep 10, 2011 8:05 AM

 Messages: [ Previous | Next ]
 fsalehi Posts: 13 Registered: 8/30/11
Problem with "lsqnonlin" function in matlab
Posted: Aug 30, 2011 3:34 AM

I have a problem with 'lsqnonlin' function in matlab. I used it to optimizing this function:

objfun = @(z) y - ( z(5).*exp(-z(1).*(t-z(7)).^2).*cos(2*pi.*z(2).*(t-z(7))+z(3)) + z(6).*exp(-z(1).*(t-z(8)).^2).*cos(2*pi.*z(2).*(t-z(8))+z(4)) );

% y is my signal and I optimize a guassian pulse function for Model Base Estimation

options = optimset(options, 'MaxFunEvals', 10000, 'TolX', 1e-3, 'TolFun', 1e-2, 'MaxIter', 800, 'LargeScale', 'on', 'LevenbergMarquardt', 'on', 'DiffMaxChange', 1e-7, 'DiffMinChange', 1e-10, 'Display', 'off', 'Diagnostics', 'off');

[Z,q,w,e,r]=lsqnonlin(objfun,...
[alpha Fc amptf(1:4) phase phase],...
[alpha-(2e6)^2 Fc-(2e6) toll(1:4) [] [] ],...
[alpha+(2e6)^2 Fc+(2e6) tolu(1:4) [] [] ],options);

the problem is the result of optimization, I have 8 variable to optimizing, but in result Z, only 7 of them changes and one of them (alpha) doesnt change.

why this happend?!

Date Subject Author
8/30/11 fsalehi
8/30/11 Torsten
8/31/11 fsalehi
8/31/11 spasmous
9/1/11 fsalehi
9/6/11 Steve
9/10/11 fsalehi