% Strang 2.4/27 outer products
% June 2007, M. Kawski
%
A=triu(ones(3,3))
B=A
AB=A*B
pause
S=zeros(size(A));
for i=1:3
    A(:,i)
    B(i,:)
    N=A(:,i)*B(i,:)
    pause
    S=S+N;
end
sum_of_all_4=S
compare_AB=AB