Re: Alternative atan2 (was Re: Motion 52: final ...)
On 2013-11-27 11:46:19 +0000, John Pryce wrote:
> I think atan2 is the only one that can be "improved" by this method.
I also think so.
> Basically, for any box (yy,xx) in R^2 that doesn't contain (0,0),
> but meets the usual branch cut of atan2, the idea is to rotate the
> branch cut out of the way of the box. Depending on the rule for
> which direction to rotate, one gets different answers for the range
> of the resulting function. Bill, is that right?
>
> It's a neat idea. Jürgen, would you consider adding this to function
> to our list (recommended, I would say)? Who supports this?
IMHO, the alternative function should have a different name, so that
it is not confused with the usual atan2 function (standardized in
ISO C, POSIX and IEEE 754-2008 at least). This traditional atan2
function should still be supported in P1788, as it could be useful
to obtain proved results (enclosures...) on this function.
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Vincent Lefèvre <vincent@xxxxxxxxxx> - Web: <http://www.vinc17.net/>
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