You need to add indexes to your outputs. Typically, it is usually appropriate to use your loop index value as the index, however, because your index is not always a real positive integer you will need to add some kind of counter into the loop.
c = 1;
for rho = 5:.025:50
[x(c),y(c),z(c)] =
xs(c) =
...
c = c + 1;
end
It may take some tweaking, but that's the basic idea.
