//exec('rand.1.ex')
//create normally distributed random vector
//y where y~N(m,L)
   m=[-2;1;10];
   L=[3 2 1;2 3 2;1 2 3];
   L2=chol(L);
   rand('seed');
   rand('normal');
   x=rand(3,1)
   y=L2'*x+m
