Just to clear up one more possible point: the rational? predicate actually recognizes inexact numbers, eg:
[robby@penghu] ~/git/plt/collects/drracket/private$ racket Welcome to Racket v5.1.3.9. > (rational? (sqrt 2)) #t Robby On Fri, Sep 30, 2011 at 11:18 AM, Mark Engelberg <[email protected]> wrote: > I'm amazed at how long I've gone with the misconception that: > Exact Numbers = Integers union Rationals > Inexact Numbers = Floating Point numbers > (Frankly, I never really thought much about what infinities were. I assumed > they were a separate, distinct type). > > When I saw in the docs for round that it returns an integer, and I was > getting an inexact number, I was sure it was a mistake. Thanks for helping > me straighten out my thinking on this. I can see how you might want to test > an inexaxct number for whether it is the floating point approximation of an > "integer", so that makes sense. Still seems weird and inconvenient for > round to give you back an inexact integer rather than an exact one, but I > can see now how this behavior matches the standard. > > Thanks, > > Mark > > > _________________________________________________ > For list-related administrative tasks: > http://lists.racket-lang.org/listinfo/users > _________________________________________________ For list-related administrative tasks: http://lists.racket-lang.org/listinfo/users
