% 
% Written by:
% -- 
% John L. Weatherwax                2006-12-19
% 
% email: wax@alum.mit.edu
% 
% Please send comments and especially bug reports to the
% above email address.
% 
%-----

randn('seed',0); rand('seed',0); 

n = 4; 

% create a matrix A: 
A = randn(n); 

% make A diagonally dominant: 
for ii=1:n,
  A(ii,ii) = 10; 
end

% create a right hand side: 
f = randn(n,3); 

x = redBlackGSeidel(A,f);

norm(A*x-f)