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Re: implementation categories, exact rationals

This page is part of the web mail archives of SRFI 77 from before July 7th, 2015. The new archives for SRFI 77 contain all messages, not just those from before July 7th, 2015.

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 <jcowan@xxxxxxxxxxxxxxxxx> 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