implementation categories, exact rationals
Aubrey Jaffer
(14 Oct 2005 18:29 UTC)
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Re: implementation categories, exact rationals John.Cowan (14 Oct 2005 19:26 UTC)
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Re: implementation categories, exact rationals
Aubrey Jaffer
(14 Oct 2005 19:38 UTC)
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Re: implementation categories, exact rationals
John.Cowan
(14 Oct 2005 20:16 UTC)
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Re: implementation categories, exact rationals
bear
(16 Oct 2005 18:08 UTC)
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Re: implementation categories, exact rationals
Michael Sperber
(17 Oct 2005 07:44 UTC)
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Re: implementation categories, exact rationals
Aubrey Jaffer
(17 Oct 2005 21:59 UTC)
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Re: implementation categories, exact rationals
Bradley Lucier
(17 Oct 2005 22:07 UTC)
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Re: implementation categories, exact rationals John.Cowan 14 Oct 2005 19:26 UTC
Aubrey Jaffer scripsit: > What is the rationale for mandating exact rationals? Over 15 years I > have written numerical Scheme code for everything from symbolic > algebra to Galois fields to linear systems to optics simulations > without needing exact rationals. > > A case could be made if (expt -26. 1/3) returned -2.9624960684073702; > but I know of no Scheme implementation that does so. Why would that be desirable? 1.48124803420369+2.5655968538523i (thus Chicken, and Petite Chez just adds a few more significant digits) is a more sensible value. -- John Cowan <xxxxxx@reutershealth.com> www.ccil.org/~cowan www.reutershealth.com Micropayment advocates mistakenly believe that efficient allocation of resources is the purpose of markets. Efficiency is a byproduct of market systems, not their goal. The reasons markets work are not because users have embraced efficiency but because markets are the best place to allow users to maximize their preferences, and very often their preferences are not for conservation of cheap resources. --Clay Shirkey