
 n = 400;
 for jay = 1:4
   if jay > 1; oldtime = time; end
   M = randn(n);
   A = M'*M;
   t = cputime;
   R = chol(A);
   matrixsize = n
   time = cputime - t
   if jay > 1; ratio = time/oldtime, end
   n = 2*n;
 end
