clear all;  close all;
n=input('n = ');

A = zeros(n,n);
for i=1:n-1,
   A(i,i) = -2;
   A(i,i+1) = 1; 
   A(i+1,i) = 1;
end
A(n,n) = 2;

x0 = rand(n,1); tol = 1.0e-8;

[my_eig,x,k] = my_power(A, tol, x0);

%Compare the error:

  eig_e = min(eig(A));         % Because A is negative definite.
  e = my_eig - eig_e
  e2 = norm(A*x - my_eig*x)