My matlab code is giving me this error "Too many outputs requested". If someone can help me solve this?

My code is as follows:

function nn_ewn=optim_ewn(c_ewn)

case_ewn=case_one_ewn_gen(c_ewn);

a_cost=[]; 
for ii=1:1:size(case_ewn,2)
  tmp_ewn=case_ewn{ii};
  [t_cost t_Ic t_current t_a2]=find_cost(tmp_ewn);
  u=fitdist(t_Ic,'normal');  
  wu=u.sigma;  wn=u.mu;

    u_arr=[];   cost_arr=[];    count=1;
    while 1
        ste=sum(tmp_ewn);
        tmp2_ewn=tmp_ewn;

        Hy=t_Ic-wn;
        v1=max(Hy);         v1_pos=find(Hy==v1);
        v2=min(Hy);         v2_pos=find(Hy==v2);

        v4_pos=find(t_Ic==max(t_Ic));
        v5_pos=find(t_Ic==min(t_Ic));
        Ht=sort(t_Ic(:));
        v6_pos=find(t_Ic==Ht(2));

        d=1;

        tmp3_ewn=tmp2_ewn;

        if (tmp2_ewn(v1_pos) == 4 && tmp2_ewn(v2_pos) == 4) || (tmp2_ewn(v1_pos) == 12 && tmp2_ewn(v2_pos) == 12)            
            if (tmp2_ewn(v5_pos) == 4 && tmp2_ewn(v6_pos) == 4) || (tmp2_ewn(v5_pos) == 12 && tmp2_ewn(v6_pos) == 12)
                tmp3_ewn=tmp2_ewn;
                break
            elseif (tmp2_ewn(v5_pos) == 4 && tmp2_ewn(v6_pos) ~= 4) || (tmp2_ewn(v5_pos) ~= 12 && tmp2_ewn(v6_pos) == 12)
                tmp3_ewn(v5_pos)=tmp2_ewn(v5_pos)+d;
                tmp3_ewn(v6_pos)=tmp2_ewn(v6_pos)-d; 
            elseif (tmp2_ewn(v5_pos) ~= 4 && tmp2_ewn(v6_pos) == 4) || (tmp2_ewn(v5_pos) == 12 && tmp2_ewn(v6_pos) ~= 12)
                tmp3_ewn(v5_pos)=tmp2_ewn(v5_pos)-d;
                tmp3_ewn(v6_pos)=tmp2_ewn(v6_pos)+d;
            end
        elseif (tmp2_ewn(v1_pos) == 4 && tmp2_ewn(v2_pos) ~= 4) || ...
             (tmp2_ewn(v1_pos) ~= 4 && tmp2_ewn(v2_pos) == 4) || (tmp2_ewn(v1_pos) ~= 4 && tmp2_ewn(v2_pos) ~= 4) || ...
             (tmp2_ewn(v1_pos) == 12 && tmp2_ewn(v2_pos) ~= 12) || ...
             (tmp2_ewn(v1_pos) ~= 12 && tmp2_ewn(v2_pos) == 12) || (tmp2_ewn(v1_pos) ~= 12 && tmp2_ewn(v2_pos) ~= 12)

             if (min(tmp2_ewn) >= 4 || max(tmp2_ewn) <= 12) && ...
                   (tmp2_ewn(v4_pos) >= 4 || tmp2_ewn(v5_pos) <= 12)
                tmp3_ewn(v1_pos)=tmp2_ewn(v1_pos)-d;
                tmp3_ewn(v2_pos)=tmp2_ewn(v2_pos)+d;
                if tmp3_ewn(v1_pos) < 4 || tmp3_ewn(v2_pos) > 12
                    for jj=1:1:length(t_Ic)
                        v3_pos=find(t_Ic==Ht(jj));                                   % v3_pos is second minimum
                        if (tmp2_ewn(v3_pos) == 4) || (tmp2_ewn(v3_pos) == 12)       %R
                           tmp_ewn=tmp2_ewn; 
                           continue
                        elseif (tmp2_ewn(v3_pos) ~= 4 && tmp2_ewn(v3_pos) >= 4)|| (tmp2_ewn(v3_pos) ~= 12 && tmp2_ewn(v3_pos) <= 12)
                           tmp3_ewn(v3_pos)=tmp2_ewn(v3_pos)+d;
                   %        tmp3_ewn(v3_pos)=tmp2_ewn(v3_pos)-d;   
                           tmp3_ewn(v4_pos)=tmp2_ewn(v4_pos)-d;
                           break
                        end
                    end
                end                                   
             end    
        end

        if min(tmp3_ewn) < 4 
             n=length(tmp3_ewn);
             tmp3_ewn(v4_pos)=4;
             tmp3_ewn(n)=ste-sum(tmp3_ewn(1:end-1));
        end
        if max(tmp3_ewn) > 12 
             n=length(tmp3_ewn);
             tmp3_ewn(v5_pos)=12;
             tmp3_ewn(n)=ste-sum(tmp3_ewn(1:end-1));
        end

        tmp3_ewn

        [g_cost g_Ic g_current g_a2]=find_cost(tmp3_ewn);
         u1=fitdist(g_Ic,'normal');

        if wu > u1.sigma   
           wu=u1.sigma
           tmp_ewn=tmp3_ewn;

           u_arr(count)=u1.sigma
           cost_arr(count)=g_cost
           g_Ic_cell{count}=g_Ic; 
           tmpe_cell{count}=tmp3_ewn';

           cost_arr

           count=count+1;
           continue
        elseif wu < u1.sigma
           u_m_pos=find(u_arr == min(u_arr));                
           gt_ewn=tmpe_cell{u_m_pos};
           gt_cost=cost_arr(u_m_pos);
           gt_Ic=g_Ic_cell{u_m_pos};
           break
        end        end                                                                                                         
    a_cost=[a_cost,gt_cost];    
    Ic_cell{ii}=gt_Ic;
    n_ewn{ii}=gt_ewn;
  end

n=length(n_ewn)
a_cost
mp_pos=find(a_cost==min(a_cost));
nn_ewn=n_ewn{mp_pos};

Error is..:

    Too many outputs requested.  Most likely cause is missing [] around
    left hand side that has a comma separated list expansion.

    Error in optim_ewn (line 98)
               gt_ewn=tmpe_cell{u_m_pos};

Can someone help me solve this problem. Thank you.

Answer 1

[Jan]

u_m_pos=find(u_arr == min(u_arr));                
gt_ewn=tmpe_cell{u_m_pos};

The message appears, if the minimal value min(u_arr) appears more than once inside u_arr.

If you want the index of one minimum only:

[~, u_m_pos] = min(u_arr);

Answer 2

[Stephen23]

There is nothing preventing you from having zero, one, or more values returned. You need to take into account those situations. One solution is to simply return a subset of the cell array:

gt_ewn = tmpe_cell(u_m_pos);

Read more about cell array indexing here:

https://www.mathworks.com/help/matlab/matlab_prog/access-data-in-a-cell-array.html