function [v,lambda,rr]=PowerMethod(A);
% Power method for the Hermitian eiegenvalue problem
tol=1e-13;
n=max(size(A));
v=rand(n,1); v=v/norm(v);
rr=[];
while 1,
  u=A*v;
  lambda=v'*u
break
  r=v-u/lambda;
  rnorm=norm(r), rr=[rr;rnorm];
  if rnorm<tol, break, end
  v=u/norm(u);
end
% Copyright (C) 2006-2007 Artan Borici.
% This program is a free software licensed under the terms of the GNU General Public License