function [ J ] = cost( z )

   a = z(1);
   b = z(2);
   c = z(3);
   d = z(4);
   e = z(5);

   w = [0:0.1:10]';
   s = j*w;

   Gideal = w .* (w < 5);

   G = a*s ./ ( (s.^2+b*s+c) .* (s.^2 + d*s + e) );

   e = abs(Gideal) - abs(G);

   J = sum(e .^ 2);

   plot(w,abs(Gideal),w,abs(G));
   pause(0.01);

end