Re: [9fans] circular fonctions: precision?

[tlaronde@polynum.com]

On Mon, Oct 03, 2011 at 09:03:50AM -0400, Russ Cox wrote:
> On Sun, Oct 2, 2011 at 12:38 PM,  <tlaronde@polynum.com> wrote:
> > Is there some documentation about the precision of the circular (i.e
> > trigonometric) fonctions, depending on the (plan9) implementation and
> > the hardware?
>
> They are not terribly accurate.
>
> If you need accurate versions, the best I know are the ones
> that were written at Sun and included in the FreeBSD math library.
> There are copies on any FreeBSD machine and also in the
> vx32 distribution: http://code.swtch.com/vx32/src/tip/src/libvxc/msun.
>
> For Go, we started with implementations of the Plan 9 library
> algorithms but have been slowly replacing them with implementations
> of the Sun/FreeBSD algorithms for the improved accuracy.

Thanks for the tips. I will put the various clues given in the thread at
least to have a better understanding about what my code relies upon.
--
        Thierry Laronde <tlaronde +AT+ polynum +dot+ com>
                      http://www.kergis.com/
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