On Fri, 14 Oct 2022 at 14:58, Taco Hoekwater via ntg-context <ntg-context@ntg.nl> wrote:


> On 14 Oct 2022, at 14:26, Alan Braslau via ntg-context <ntg-context@ntg.nl> wrote:
>
> Are you using MP in scaled integer or in doubleprecision mode?
>
> I have not looked into the MP angle operator code, but my suspicion is that it is based on some super-clever John Hobby scheme optimized for scaled integer calculations.

The scaled version of “angle” is a handwritten approximation in web, not using
any math library. I really doubt that that code is faster than calling atan2()
on a modern machine, but I’ve kept it in because using a lib might give slightly
different results.

iirc, in metapost  the whole scaled number system has no dependency  from any external math library
(I have not checked the lmtx source yet).