[Python-ideas] [Python-Dev] matrix operations on dict :)

[Stephen J. Turnbull]

Mark Janssen writes:

 > The math (in my world) simply decided that factorial(0)=1 as the
 > convention of "an empty product" (Wikipedia::Factorial).

In modern math (ie, post-Eilenberg-Mac Lane), it's not really a
convention (unlike, say, Euclid's Parallel Postulate); it's the only
way to go if you want the idea of product to generalize.  If you don't
understand that, I have serious doubts that you know what you're
talking about.  If you do understand that, please take care to be more
precise.