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Re: My suggestions to the R6RS committee about numerics
======= 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.