Gregory Ewing writes: > Chris Angelico wrote: > > > Question: How many factorial functions are implemented because a > > program needs to know what n! is, and how many are implemented to > > demonstrate recursion (or to demonstrate the difference between > > iteration and recursion)? :)
(I can't get to the parent directly, so I follow up indirectly.) Factorials become an interesting demonstration of recursion when done well. There's a paper by Richard J. Fateman, citing Peter Luschny: <http://www.cs.berkeley.edu/~fateman/papers/factorial.pdf> <http://www.luschny.de/math/factorial/FastFactorialFunctions.htm> Fateman's "major conclusion is that you should probably not use the 'naive' factorial programs for much of anything". I take this to include their use as examples of recursion, unless the purpose is to make the idea of recursion look bad. -- http://mail.python.org/mailman/listinfo/python-list