function test_eig(n)

if nargin == 0; n = 50; end

A = rand(n);
A = A + A';
if exist('my_eig','file')
   tic; d = my_eig(A); toc
end
if exist('yz_eig','file')
   tic; d = yz_eig(A); toc
end
tic; dm = eig(A); toc
relerr = norm(sort(d)-sort(dm))/norm(dm);
fprintf('rel_err: %6.2e\n',relerr)