More detailed output function in optimization

Hello,

I think I have a simple question but found it difficult to fix it myself.

In doing the optimization we can have 'our' output function. The following represents roughly my code and my output function:

Extra_param = A number;

options=optimoptions('fmincon','OutputFcn',@myoutput,'StepTolerance',10^(-8));

fmincon(cost,x0,[],[],[],[],lb,ub,[],options);

function stop = myoutput(x,optimvalues,state);

stop = false;

if isequal(state,'iter')

disp(num2str(x));

end

end

I would like the output function to dsplay me another parameter called 'Extra_param' which is not related to the optimum values or optimum state. It is just an extra parameter (and has nothing to do with the optimization problem being solved). so, I would like something like bellow:

function stop = myoutput(x,optimvalues,state,Extra_param);

stop = false;

if isequal(state,'iter')

disp(num2str(x));

disp(num2str(Extra_param));

end

end

But, unfortunately I get the following error message:

Unrecognized function or variable 'Extra_param'.

[Walter Roberson]

@myoutput

should become

@(x,op,st)myoutput(x,op,st,Extra_param)

This assumes that the value is known before you start optimization

[Mohammad Shojaei Arani]

Yes Walter. Great!

Thanks man!