[Nauty-list] Two Technical questions

[Chad Brewbaker]

I have a two technical questions about NAUTY:

1. Could you explain in detail the longprune() method used once per tcell in the
depth first search? I get shortprune(), but longprune() is a little harder to
grasp. 

2.Other than vanilla partition refinement what invarients does dreadnaut use by
default? Backtracing the function pointers is a bit confusing :)

Thanks,
Chad Brewbaker