In reply to Jay.

Haha! It's a good thing that you are learning SAS, however, division by 0 may not be bad either, just use divide() function instead of /. So instead of 1/0 you would write divide(1,0), then you can burn down your computer or else. Did you miss that function in the blog? And if you are a comic lover, you might like another blog Dividing by zero with SAS. Enjoy!