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

[John Cowan <cowan@x>]

Andrew Robbins scripsit:

> Consider the logarithm of a directed infinity. (log (make-polar +inf.0
> y)) should be +inf.0+yi, whatever y is. If y is an exact number, then
> (imag-part (log ...)) should also be exact. I'm not sure how many Scheme
> implementations actually store exact polar complex numbers this way,
> but it helps keep numbers exact.

None of the ones on my list do.  They all work like this:

(make-polar +inf.0 +nan.0) => +nan.0+nan.0i
(make-polar +inf.0 2) => -inf.0+inf.0i
(log (make-polar +inf.0 2) => +nan.0+2.356194490192345i

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