function ex_1_4_22()
% 
%
% Written by:
% -- 
% John L. Weatherwax                2006-03-28
% 
% email: wax@alum.mit.edu
% 
% Please send comments and especially bug reports to the
% above email address.
% 
%-----

A = [ 9 3 3 ; 3 10 7; 3 5 9 ]; 
R_a = chol(A)
R_a.' * R_a

B = [ 4 2 6 ; 2 2 5 ; 6 5 29 ]; 
R_b = chol(B)
R_b.' * R_b

try
C = [ 4 4 8 ; 4 -4 1 ; 8 1 6 ];
R_c = chol(C)
catch
end

try 
D = [ 1 1 1 ; 1 2 2 ; 1 2 1 ]; 
R_d = chol(D)
catch
end