[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

*To*: John Cowan <cowan@x>*Subject*: Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0*From*: Mark H Weaver <mhw@x>*Date*: Wed, 19 Dec 2012 18:21:28 -0500*Cc*: scheme-reports <scheme-reports@x>*In-reply-to*: <20121219221955.GH4477@mercury.ccil.org> (John Cowan's message of "Wed, 19 Dec 2012 17:19:55 -0500")*References*: <20121214223854.GX29857@mercury.ccil.org> <CAGUt3y55KEVFn=6_i9yRXR8w_e8Nk2tN7QGCF8rEhYTs2Xgrjw@mail.gmail.com> <878v8z5iq8.fsf@tines.lan> <874njn5b65.fsf@tines.lan> <20121215204015.GG13463@mercury.ccil.org> <87obhv3ts0.fsf@tines.lan> <20121215231548.GC10312@mercury.ccil.org> <87bodu4r0r.fsf@tines.lan> <20121216041031.GE10312@mercury.ccil.org> <87pq25yh5s.fsf@tines.lan> <20121219221955.GH4477@mercury.ccil.org>

John Cowan <cowan@x> writes: > Or is what you mean that some Schemes, when asked for the imag-part of > 2.0, may return 0.0 rather than 0? Yes, that's exactly what I mean. I know that SCM and Gauche do this, and I suspect it's quite common. > I can check for that possibility when I'm back home. > >> Another test that would be worthwhile is this: >> >> (list (eqv? +0.0 -0.0) >> (eqv? (make-rectangular +0.0 1.0) >> (make-rectangular -0.0 1.0)) >> (eqv? (make-rectangular 1.0 +0.0) >> (make-rectangular 1.0 -0.0)) >> >> I wouldn't be surprised if some Schemes distinguish signed zeroes in the >> real part but not in the imaginary part. If an implementation discards >> inexact zero imaginary parts, then it probably discards the sign as well >> as the exactness. > > I'll try that. Thanks! 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:*John Cowan <cowan@x>

**References**:**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:*Sascha Ziemann <ceving@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:*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:*John Cowan <cowan@x>

- Prev by Date:
**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0** - Next by Date:
**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0** - Previous by thread:
**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0** - Next by thread:
**Re: [Scheme-reports] Strong win later reversed: Real numbers have imaginary part #e0** - Index(es):