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Re: [Scheme-reports] Mixed exactness in complex numbers?

Peter Bex scripsit:

> The report occasionally mentions "an inexact complex number" or "an
> exact complex number".  Does this imply that there's no such thing as
> a complex number of mixed exactness?

An exact complex number is one whose real and imaginary parts are exact,
and I have added a definition to this effect on trunk.  All my Schemes
already behave this way.

> Other Schemes I've looked at (not that many, though) return a normalised
> complex number with both real and imaginary parts converted to inexact.

For a list of which schemes have which representations, see
http://trac.sacrideo.us/wg/wiki/ComplexRepresentations .

> I just noticed, the text below the inexact? and exact? predicates says
> "For any Scheme number, precisely one of these predicates is true"

This is correct given the definition above.

John Cowan  <cowan@x>  http://ccil.org/~cowan
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 Shirky

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