optimization function in matlab

i would like to ask about the optimization in matlab function that works with multi variable input with each input has different boundaries the output is only one variables

Answer 1

[John D'Errico]

help fmincon

Or, as found on the file exchange, fminsearchbnd.

[mohammed hussein]

thank you John D'Errico for answering me

i am trying these function a lot of time but it doesn't work

i have the equation

Function =(X-5)^2+(Y+6)^2+Z

when the boundary of

X from 0 to 1
Y from -1 to 2
Z from 2 to 3

i did that in matlab but i doesn't work

 fun = inline('(x-5)^2+(y+6)^2+Z');

 x0 = [1 1 1];
 Lb=[0 -1 2];
 Ub=[1 2 3];
 [x,fval,exitflag,output] = fminsearch(fun,x0,Lb,Ub);
 disp(fval)

it gives me error

Error in fminsearch (line 190)
fv(:,1) = funfcn(x,varargin{:});

Error in Untitled (line 5)
 [x,fval,exitflag,output] = fminsearch(fun,x0,Lb,Ub);

can you help me with that problem

thank you

[Walter Roberson]

fminsearch does not permit boundary conditions. As John indicated, you need to use fmincon() or you need to get the fminsearchbnd File Exchange contribution.

[mohammed hussein]

thank you Walter Roberson i used the fmincon()

 fun = inline('(x-5)^2+(y+6)^2+Z');
 x0 = [1 1 1];
 Lb=[0 -1 2];
 Ub=[1 2 3];
 [x,fval,exitflag,output] = fmincon(fun,x0,Lb,Ub);
 disp(fval)

but also gives me the error

Error using fmincon (line 293) Row dimension of A is inconsistent with length of b.

Error in Untitled (line 5) [x,fval,exitflag,output] = fmincon(fun,x0,Lb,Ub);

[John D'Errico]

Read the help for fmincon.

You cannot simply pass in a list of variables in any order as arguments and expect fmincon to know that the 3rd and 4th arguments are to be interpreted as bounds.

READ THE HELP!!!!!

[x,fval,exitflag,output] = fmincon(fun,x0,[],[],[],[],Lb,Ub);

As you were passing in those arguments, fmincon thought they were to be treated as the equations for a set of linear INEQUALITY constraints. As such, what it thought were A and b were inconsistent in size.

[mohammed hussein]

Thank you john

Answer 2

[Torsten]

fun = @(x)(x(1)-5)^2+(x(2)+6)^2+x(3);
x0 = [1 1 1];
Lb=[0 -1 2];
Ub=[1 2 3];
[x,fval,exitflag,output] = fmincon(fun,x0,[],[],[],[],Lb,Ub);
disp(fval)

Best wishes

Torsten.

[mohammed hussein]

Thank you Torsten It is working