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Re: My suggestions to the R6RS committee about numerics

This page is part of the web mail archives of SRFI 70 from before July 7th, 2015. The new archives for SRFI 70 contain all messages, not just those from before July 7th, 2015.

======= At 2005-06-03, 00:25:02 bear wrote: =======

>In particular, be careful not to assume that all complex numbers
>are internally represented in the same way; several implementations,
>I believe, use both polar and cartesian representations internally.

Agree. And I think internal polar representations is more prefered
than cartesian in some cases.

>Finally, from a mathematical point of view, a number is either
>inexact or exact; this includes complex numbers.  A few
>implementations allow differing exactness in the real and
>imaginary parts of a complex number.  This is a fact, but the
>fact lies at some intermediate position between being a mere
>artifact of the representation and a mathematical error.
>Consult a number theorist to understand more fully the nature
>of this error; it is beyond my feeble ability to explicate.

What if we know (exactly) a number is an imaginary number, but only
know ineaxtly it's magnitude?  "0+1.0i" seems nature. 

And for polar representations, a number with exact angle but inexact
magnitude also seems nature.

Chongkai Zhu