On Fri, Jun 22, 2012 at 5:43 PM, Matthew Rocklin <[email protected]> wrote: > > Some non-Basic element types are important. True, False and None are notable > examples. Frozenset is another. SymPy.stats uses frozensets pretty heavily > because they're substantially faster than FiniteSet. I'm in favor of > avoiding this problem if possible.
All right, that sounds plausible. I do have some questions, though. I am still a little bit surprised that there is no type in SymPy to store True and False. However, if there is a reason for such a class not to exist, I wonder whether allowing True and False in FiniteSet would be totally consistent. Further, I can't really grasp the point of having None in a FiniteSet. I'd be happy to see an example where None couldn't be substituted for an EmptySet or a special value belonging to the type we are interested in. Yet further, if some code depends on frozenset's for speed, where and why does it use FiniteSet? I really really don't like the idea of having frozenset's in FiniteSet's; it sounds very inconsistent to me. However, I may be missing some important points; I'd be happy to be corrected. Sergiu -- You received this message because you are subscribed to the Google Groups "sympy" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/sympy?hl=en.
