for loop inside parfor loop

Hello, i am getting the following error for this loop.

Error using In (line 78) Error: The variable f in a parfor cannot be classified. See Parallel for Loops in MATLAB, "Overview".

     parfor j = 1:size(lam,2);
     c(:,j) = fminunc(@(c) (chi1(c, K0_com)), cint, options);
        for i = 1:Steps*Steps
            f(i,j) = K0_com(:,i)'*c(:,j);
            f(i,j) = (f(i,j)>0)*f(i,j);
        end
     end

How can I fix this? I did not see any warning or error when I wrote this.

Answer 1

[Matt J]

I would take the processing of f out of the loop altogether. Just post-compute it using vectorized methods:

     parfor j = 1:size(lam,2);

       c(:,j) = fminunc(@(c) (chi1(c, K0_com)), cint, options);

     end

      f=K0_com.'*c;
      f=f.*(f>0);