function f = fnctmxap(x);

% This is a matrix rank-1 approximation problem.

%  Find a rank-1 matrix so that
%  norm(my_A - x(1:my_n/2)*x(my_n/2+1:my_n)','fro')
%  is as small as possible.
%  The matrix my_A is my_n/2 x my_n/2 in size.

%  x should be my_n x 1.

global my_A my_n

f = norm(my_A - x(1:my_n/2)*x(my_n/2+1:my_n)','fro')^2;