Fminsearch X0 interval
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From: Adrian gavrila on 14 Apr 2010 11:29 Hello, I have an issue, I have an fminsearch function but I need to input more that one value, that is done, but as I run the function X0 goes out of bound: x0=13.0e-3:0.1e-3:13.5e-3 options =optimset('Display','iter','MaxIter',100,'MaxFunEvals',40,'OutputFcn',@outfun) [y,fval,exitflag,output]=fminsearch(@(y) PMSM_m_mod_optimiz(y),x0,options); In y now it is only one variable now: y(1) from PMSM_m_mod_optimiz, I can put as many as 7 variables (this is done). What I need to do is put for each variable an interval, like for :y(1)=[13.0...13.5] so Fminsearch does not have to go over that. I have tried x0=13.0e-3:0.1e-3:13.5e-3 but not working still going out of bound. After this I need to implement the other 6 left variables and so I need to make a matrix with several lines, each line storing a variable.Correct me if my I judgment is wrong. Please help me with this issue. Thank you.
From: Steven Lord on 14 Apr 2010 11:56 "Adrian gavrila" <adig_coool(a)yahoo.com> wrote in message news:hq4n02$8c6$1(a)fred.mathworks.com... > Hello, > > I have an issue, > I have an fminsearch function but I need to input more that one value, > that is done, but as I run the function X0 goes out of bound: > > > x0=13.0e-3:0.1e-3:13.5e-3 > options > =optimset('Display','iter','MaxIter',100,'MaxFunEvals',40,'OutputFcn',@outfun) > [y,fval,exitflag,output]=fminsearch(@(y) > PMSM_m_mod_optimiz(y),x0,options); > > In y now it is only one variable now: y(1) from PMSM_m_mod_optimiz, I can > put as many as 7 variables (this is done). > > What I need to do is put for each variable an interval, like for > :y(1)=[13.0...13.5] so Fminsearch does not have to go over that. > I have tried x0=13.0e-3:0.1e-3:13.5e-3 but not working still going out of > bound. > > After this I need to implement the other 6 left variables and so I need to > make a matrix with several lines, each line storing a variable.Correct me > if my I judgment is wrong. > > Please help me with this issue. If you're looking to perform a CONSTRAINED search (bounds are a type of constraint) then you can't use FMINSEARCH. http://www.mathworks.com/access/helpdesk/help/techdoc/ref/fminsearch.html "Find minimum of ***_unconstrained_*** multivariable function using derivative-free method" [Emphasis mine.] Since your function is not a function of one variable but as many as seven, FMINBND won't work. Look at FMINCON in Optimization Toolbox. -- Steve Lord slord(a)mathworks.com comp.soft-sys.matlab (CSSM) FAQ: http://matlabwiki.mathworks.com/MATLAB_FAQ
From: John D'Errico on 14 Apr 2010 12:09
"Adrian gavrila" <adig_coool(a)yahoo.com> wrote in message <hq4n02$8c6$1(a)fred.mathworks.com>... > Hello, > > I have an issue, > I have an fminsearch function but I need to input more that one value, > that is done, but as I run the function X0 goes out of bound: > > > x0=13.0e-3:0.1e-3:13.5e-3 > options =optimset('Display','iter','MaxIter',100,'MaxFunEvals',40,'OutputFcn',@outfun) > [y,fval,exitflag,output]=fminsearch(@(y) PMSM_m_mod_optimiz(y),x0,options); > > In y now it is only one variable now: y(1) from PMSM_m_mod_optimiz, I can put as many as 7 variables (this is done). > > What I need to do is put for each variable an interval, like for :y(1)=[13.0...13.5] > so Fminsearch does not have to go over that. > I have tried x0=13.0e-3:0.1e-3:13.5e-3 but not working still going out of bound. > > After this I need to implement the other 6 left variables and so I need to make a matrix with several lines, each line storing a variable.Correct me if my I judgment is wrong. > > Please help me with this issue. > Thank you. You cannot use fminsearch as Steve says, but you CAN use fminsearchbnd, as found on the File Exchange. http://www.mathworks.com/matlabcentral/fileexchange/8277 This tool allows upper and lower bound constraints on the unknowns. HTH, John |