not able to use fminsearch in minimizing Max_error function from a vector delta appended to the handle structure in GUI.

code bugging needs support:

    handles = Max_error(handles);
    delta = handles.calculated_parameters.delta;
    delta_init = handles.calculated_parameters.delta;
    handles.calculated_parameters.delta = fminsearch(@(delta) Max_error(handles),delta_init);
    %handles.calculated_parameters.delta = fminsearch(@(handles) Max_error(handles),delta_init);   

 function data = Max_error(handles)
       handles = radial_LMSE(handles);   
       handles.calculated_parameters.Max_error = sqrt((max(handles.calculated_parameters.error_Xu))^2+(max(handles.calculated_parameters.error_Yu))^2);
       data = handles;

function data =  radial_LMSE(handles)

[Geoff Hayes]

Jacques - please include the complete function (all code) that the above code belongs to as it is unclear (to me) what is happening. What is Max_error and what is the purpose of the following line

 handles = Max_error(handles);

when the same is called in each of the fminseach function calls? Does the above code generate an error, and if so, what is the error?