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*To*: schlie@xxxxxxxxxxx*Subject*: Re: Nitpick with FLOOR etc.*From*: Aubrey Jaffer <agj@xxxxxxxxxxxx>*Date*: Mon, 18 Jul 2005 13:39:36 -0400 (EDT)*Cc*: srfi-70@xxxxxxxxxxxxxxxxx*Delivered-to*: srfi-70@xxxxxxxxxxxxxxxxx*In-reply-to*: <BF00818E.ADB9%schlie@xxxxxxxxxxx> (message from Paul Schlie on Sun, 17 Jul 2005 21:43:42 -0400)*References*: <BF00818E.ADB9%schlie@xxxxxxxxxxx>

| 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. From SRFI-70: "... 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..

**Follow-Ups**:**Re: Nitpick with FLOOR etc.***From:*Paul Schlie

**References**:**Re: Nitpick with FLOOR etc.***From:*Paul Schlie

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