%function []=prob_9_3_22()
%
% Written by:
% -- 
% John L. Weatherwax                2006-12-20
% 
% email: wax@alum.mit.edu
% 
% Please send comments and especially bug reports to the
% above email address.
% 
%-----
  
clc; close all; 

n = 4; 
A = gen_der2_mat(n); 

[Q,T]=lanczos(A);

disp('Q^T Q is equal to' ); 
(Q.') * Q 
disp( 'A*Q should equal Q T, the norm of the difference between the two matrices is' ); 
norm( A * Q - Q * T )