[Python-ideas] Fwd: Trigonometry in degrees

[Matt Arcidy]

On Mon, Jun 18, 2018, 19:25 Chris Barker via Python-ideas <
python-ideas at python.org> wrote:

> On Sat, Jun 16, 2018 at 10:57 PM, Tim Peters <tim.peters at gmail.com> wrote:
>
> Ya, decimal fp doesn't really solve anything except the shallow surprise
>> that decimal fractions generally aren't exactly representable as binary
>> fractions.  Which is worth a whole lot for casual users, but doesn't
>> address any of the deep problems (to the contrary, it makes those a bit
>> worse).
>>
>
> It's my suspicion that the story is the same with "degree-based" trig :-)
>
> Which is why, if you want "nice-looking" results, it seems one could
> simply accept a decimal digit or so less precision, and use the "regular"
> FP trig functions, rounding to 14 or so decimal digits.
>
> Though if someone really wants to implement trig in native degrees -- more
> power to 'em.
>
> However -- if this is really such a good idea -- wouldn't someone have
> make a C lib that does it? Or has someone? Anyone looked?
>


quite a few in fact, including cos(n*pi)
https://www.boost.org/doc/libs/1_52_0/boost/units/cmath.hpp




> -CHB
>
>
> --
>
> Christopher Barker, Ph.D.
> Oceanographer
>
> Emergency Response Division
> NOAA/NOS/OR&R            (206) 526-6959   voice
> 7600 Sand Point Way NE   (206) 526-6329   fax
> Seattle, WA  98115       (206) 526-6317   main reception
>
> Chris.Barker at noaa.gov
> _______________________________________________
> Python-ideas mailing list
> Python-ideas at python.org
> https://mail.python.org/mailman/listinfo/python-ideas
> Code of Conduct: http://python.org/psf/codeofconduct/
>
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://mail.python.org/pipermail/python-ideas/attachments/20180618/641f0473/attachment.html>