[Python-Dev] Revamping Python's Numeric Model

Charles G Waldman cgw@fnal.gov
Sat, 4 Nov 2000 09:21:02 -0600 (CST)


Moshe Zadka writes:

 > MAL > Not sure what you mean here: perhaps .isexact() <=> can be
 > MAL > represented in IEEE ?
 > 
 > No, I meant "not represented exactly". The real meaning for that (one
 > that we might or might not promise) is that it's a float. It's a place 
 > where the numeric model takes the easy way out <wink>.

Hmm, I like almost everything about your proposal.  The above point
bothers me slightly.  Are you saying (1.0).isexact() == 0?

Also, how about long integers?  Will they, under your new proposal, be
indistinguisable from regular ints?  While this has some appeal to it
it would be problematic for C extension modules.

Finally, although I'm no Schemer, the hierarchy you suggest sounds
very Schemish to me - I know they have a similar hierarchy of numeric
types with some of these same predicates to test for integrality,
rationality, reality, exactness - maybe there is something to be
learned by studying the Scheme model?