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Re: [Scheme-reports] (angle -0.0-0.0i) should be -pi, but R7RS-draft-6 prohibits this
Mark H Weaver scripsit:
> There is widespread agreement in the relevant floating point standards
> (C99, C11, ISO/IEC 10967, and probably IEEE 754 although I haven't
> purchased a copy) that (angle -0.0-0.0i) = (atan -0.0 -0.0) = -pi, but
> the definition of 'angle' on page 36 of R7RS-draft-6 (section 6.2.6)
> asserts that -pi< (angle z)<= pi for all complex 'z'. I suggest that
> this be changed to -pi<= (angle z)<= pi.
> Another problem along the same lines: earlier on page 36, R7RS-draft-6
> asserts that the value of "log z is defined to be the one whose
> imaginary part lies in the range from -pi (exclusive) to pi
> (inclusive)", and then proceeds to define the inverse trigonometric
> functions in terms of log. That should be changed to '-pi (inclusive)'.
These changes were adopted by the WG under no-objection procedure.
You know, you haven't stopped talking John Cowan
since I came here. You must have been http://www.ccil.org/~cowan
vaccinated with a phonograph needle. cowan@x
--Rufus T. Firefly
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