FMINUNC cannot continue help?

I am trying to learn how to use fminunc, but it gives the error "Failure in initial objective function evaluation. FMINUNC cannot continue."

Help please?

Note: Updated

        for i = 1:modes
            
                params.x0 = [y0 dy0];
                params.xp = xspan;
                
                fobj = @(beta)myobj(beta, params);
                    
                for j = 1:1000   % begin convergence loop for beta
            
                    beta = fminunc(fobj, beta0);    % run optimization
            
                end % end convergence loop
            
            end

            %%
            function [err, T, Y] = myobj(beta)
            
                x0 = params.x0;
                xspan = params.xp;
                
                [T,Y] = ode45('ffunc', xspan, x0);
                err = abs(Y(end,2) + sqrt(K*L.^2 - beta)*Y(end,1));  % error
            end

Answer 1

[Matt J]

You forgot to pass your params,

 fobj = @(beta)myobj(beta,params);
 
             function [err, T, Y] = myobj(beta,params)
            
                x0 = params.x0;
                xspan = params.xp;
                
                [T,Y] = ode('ffunc', xspan, x0);
                err = abs(Y(end,2) + sqrt(K*L.^2 - beta)*Y(end,1));  % error
            end

[EB]

Oh, how rookie of me.

However, I still get the same error when I try to use the fminunc function.

[Matt J]

Well, you should use

>>dbstop if caught error

to trap it.

[EB]

It just says fobj used twice, but that is correct because I need to state my fobj, then use it for the next part.

[EB]

Still the same error.