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*To*: schlie@xxxxxxxxxxx*Subject*: Re: Nitpick with FLOOR etc.*From*: Aubrey Jaffer <agj@xxxxxxxxxxxx>*Date*: Wed, 20 Jul 2005 21:28:46 -0400 (EDT)*Cc*: srfi-70@xxxxxxxxxxxxxxxxx*Delivered-to*: srfi-70@xxxxxxxxxxxxxxxxx*In-reply-to*: <BF043BDC.AE69%schlie@xxxxxxxxxxx> (message from Paul Schlie on Wed, 20 Jul 2005 17:35:24 -0400)*References*: <BF043BDC.AE69%schlie@xxxxxxxxxxx>

| Date: Wed, 20 Jul 2005 17:35:24 -0400 | From: Paul Schlie <schlie@xxxxxxxxxxx> | | > From: Aubrey Jaffer <agj@xxxxxxxxxxxx> | > | I would presume: | > | | > | (> #i1/0 1e1000) => #f | > | > Okay. (number->string 1e1000) ==> #i+/0 | > If you meant #e1e1000, then the answer should be #t. | | yes I meant #e1e1000, which implies you'd advocate: | | (> #i1e400 #e1e1000) => #t | | which doesn't seem particularly reasonable, given that it's false, | (and honestly can't see how it can be rationalized as being otherwise). Not only that: (= 1e400 1e500). In fact, we don't need infinities to construct these inexact conundrums: (= 1e-400 1e-500). The total order of the reals is a crucial property for many applications. SRFI-70 preserves and extends the total order at the price of conundrums like (= 1e400 1e500). | nor does (inexact->exact #i1/0) => 1e306 [or whatever] seem reasonable If the conversion is unreasonable, "then a violation of an implementation restriction may be reported." procedure: exact->inexact z procedure: inexact->exact z `Exact->inexact' returns an inexact representation of z. The value returned is the inexact number that is numerically closest to the argument. If an exact argument has no reasonably close inexact equivalent, then a violation of an implementation restriction may be reported. `Inexact->exact' returns an exact representation of z. The value returned is the exact number that is numerically closest to the argument. If an inexact argument has no reasonably close exact equivalent, then a violation of an implementation restriction may be reported. | unless you propose that (- #i1/0 1) :: (- 1e306 1), thereby #1/0 | merely represents the greatest magnitude inexact value, which all | values greater than saturate to. Thereby an exact infinity would | correspondingly represent the greatest representable exact value, | which all corresponding greater values saturate to as well. You brought up exact infinities, not me. I have no use for exact infinities. But I have tried to write SRFI-70 to avoid obstructing those who claim they do.

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

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