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*To*: Alex Shinn <alexshinn@x>*Subject*: Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0*From*: Mark H Weaver <mhw@x>*Date*: Mon, 24 Dec 2012 01:25:53 -0500*Cc*: John Cowan <cowan@x>, scheme-reports <scheme-reports@x>*In-reply-to*: <CAMMPzYP-=6r5i5+LVy-LYSfnV2fiCN4LAb21d2Ot-cdmQs+PTg@mail.gmail.com> (Alex Shinn's message of "Mon, 24 Dec 2012 13:04:09 +0900")*References*: <87bodu4r0r.fsf@tines.lan> <20121216041031.GE10312@mercury.ccil.org> <87pq25yh5s.fsf@tines.lan> <20121219221955.GH4477@mercury.ccil.org> <87d2y5y6fb.fsf@tines.lan> <20121221055315.GB28661@mercury.ccil.org> <87y5grsrvm.fsf@tines.lan> <CAMMPzYMQVzkQFLsgcYAWZaFO__Y13T_kOXD+CrLqVXPQOcjXGw@mail.gmail.com> <20121221171601.GC23915@mercury.ccil.org> <CAMMPzYO5m64sWGQT2b7SSPbm=zRbVT4oEx8E-DoLLATNZxtj_w@mail.gmail.com> <20121222024255.GH8521@mercury.ccil.org> <CAMMPzYOtVMoyiE=ToLHvmNf=Lbq_FOE9v9CcrZoBrcdB_mnoVQ@mail.gmail.com> <87licqr5jz.fsf@tines.lan> <CAMMPzYMU5-h+aLd45Hu2vY-oDeRs4DiHTV9fBfo9RtiTB9ds2w@mail.gmail.com> <87sj6w8jr4.fsf@tines.lan> <CAMMPzYP-=6r5i5+LVy-LYSfnV2fiCN4LAb21d2Ot-cdmQs+PTg@mail.gmail.com>

Alex Shinn <alexshinn@x> writes: > On Mon, Dec 24, 2012 at 7:51 AM, Mark H Weaver <mhw@x> wrote: > > What external representation will you use for these numbers? For > example, even if you can efficiently handle something like this: > > (do ((i 10000000 (- i 1)) > (x 1e300 (expt x x))) > ((zero? i) (/ x))) > > What will you do if someone applies 'number->string' to the > result? > > It will use Conway's chained arrow notation, as mentioned > in my previous mail. > > What you're describing here is just tetration: > > (tetrate 1e300 100000000) That's not quite right, but anyway the precise value of this number is not relevant to my point. My question was about how such numbers would be printed, and your answer was that it might look something like this: > 1/1e300->1e7->2 My point is that the results of ordinary inexact numerical computations that are printed 0.0 on virtually every other system will apparently be printed in a non-standard notation in future Chibi. This will cause problems for portable programs that use 'number->string' on inexact numbers to produce output that is meant to be read by another program. Sections 6.2.5 and 7.1.1 of R7RS-draft-8 describe the syntax of numerical constants, and authors of portable R7RS code may reasonably expect that 'number->string' will use that syntax when applied to inexact complex numbers. Mark _______________________________________________ Scheme-reports mailing list Scheme-reports@x http://lists.scheme-reports.org/cgi-bin/mailman/listinfo/scheme-reports

**Follow-Ups**:**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*Alex Shinn <alexshinn@x>

**References**:**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*Mark H Weaver <mhw@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*John Cowan <cowan@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*Mark H Weaver <mhw@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*John Cowan <cowan@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*Mark H Weaver <mhw@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*John Cowan <cowan@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*Mark H Weaver <mhw@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*Alex Shinn <alexshinn@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*John Cowan <cowan@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*Alex Shinn <alexshinn@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*John Cowan <cowan@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*Alex Shinn <alexshinn@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*Mark H Weaver <mhw@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*Alex Shinn <alexshinn@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*Mark H Weaver <mhw@x>

**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0***From:*Alex Shinn <alexshinn@x>

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