Re: arithmetic issues

[Aubrey Jaffer <agj@xxxxxxxxxxxx>]

 | From: Bradley Lucier <lucier@xxxxxxxxxxxxxxx>
 | Date: Sun, 23 Oct 2005 14:45:49 -0500
 | 
 | > Aubrey Jaffer <agj@xxxxxxxxxxxx> writes:
 | >
 | >> When different NaNs are returned depending on the circumstances
 | >> creating them, I would like my implementation to display them
 | >> like this:
 | >>
 | >>   #<not-a-number expt>
 | 
 | If "expt" means exponent, then you don't get any more
 | information--- in IEEE arithmetic, the exponents of all NaNs of a
 | given precision are the same.

No, its expt as in EXPT, the Scheme procedure:

  (expt +inf.0 0)    ==>  #<not-a-number expt>

  (+ -inf.0 +inf.0)  ==>  #<not-a-number +>

  (/ (* 0 -inf.0) 3) ==>  #<not-a-number *>

  (+ 5 (/ 0.0 0.0))  ==>  #<not-a-number />