Function with many outputs

I have this function [Y_1,Y_2,Y_3,Y_4]=MyFun(X);

I want to optimize X according to this cost function using ga function of Matlab

J=@(X) Y_1.^2+Y_2.^2;

X=ga(J,numel(X));

How to write the cost function J knowing that Y_1 and Y_2 depend on X.

Answer 1

[Torsten]

X=ga(@cost,numel(X));

function J = cost(X);
  [Y_1,Y_2] = MyFun(X);
  J = Y_1.^2+Y_2.^2;
end

[B.E.]

Thank you