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Re: Nitpick with FLOOR etc.
| Date: Sun, 17 Jul 2005 21:43:42 -0400
| From: Paul Schlie <schlie@xxxxxxxxxxx>
| > From: Aubrey Jaffer <agj@xxxxxxxxxxxx>
| > | Date: Sun, 17 Jul 2005 13:23:26 -0400
| > | From: Paul Schlie <schlie@xxxxxxxxxxx>
| > ...
| > Exact infinities are not needed for SRFI-70.
| > | (> #e1/0 #e10^1000 #i10^300) => #t
| > |
| > | as otherwise: (> (* #e10^1000 #e10^1000) #e10^1000)
| > |
| > | :: (> #i1/0 #e10^1000) => #f
| > That conflicts with SRFI-70, which specifies that #i+1/0 compares as
| > larger than any finite real number, exact or inexact:
| - well, it should be clear that that's not going to work, as it would be
| false for most all exact implementations.
"... an inexact real number represents not a single value, but a
neighborhood of (mathematical) real numbers. ... +/0. represents real
numbers greater than can be encoded by finite inexacts in the
implementation ... -/0. represents numbers less than can be encoded by
finite inexacts in the implementation."
One might argue that large exact numbers being within the
+/0. interval make them `=' to it. But that foils transitivity for
(= (expt 10 1000) +/0. (expt 10 999)
Large exact numbers can not be greater than +/0. because the entire
real line is covered by inexact neighborhoods in SRFI-70.
So large exact numbers must be less than +/0..