degrees and radians.

[Stephen Tucker]

For what it's worth, mathematicians naturally work with angles in radians.

The mathematics of the trignonmetric functions works naturally when the
angle is expressed in radians.

For the older among us, logarithms also have a "natural" base, and that is
the number e. Back in those days, however, even the mathematicians would
use logarithm tables where the values were shown to base 10.


On Wed, Aug 24, 2016 at 6:26 AM, Steven D'Aprano <
steve+comp.lang.python at pearwood.info> wrote:

> On Wednesday 24 August 2016 14:26, Gary Herron wrote:
>
> > Do you really need anything more complex than this?
> >
> >  >>> toRadians = math.pi/180.0
> >
> >  >>> math.sin(90*toRadians)
> > 1.0
> >
> > Perhaps I'm not understanding what you mean by "clunky",  but this seems
> > pretty clean and simple to me.
>
> The math module has two conversion functions, math.radians() and
> math.degrees().
>
>
> Some other languages (Julia, by memory, and perhaps others) have dedicated
> sind(), cosd(), tand() or possibly dsin(), dcos(), dtan() functions which
> take
> their argument in degrees and are more accurate than doing a conversion to
> radians first. I'd like to see that.
>
> I've also seen languages with sinp() etc to calculate the sine of x*pi
> without
> the intermediate calculation.
>
> But if I were designing Python from scratch, I'd make sin(), cos() and
> tan()
> call dunder methods __sin__ etc:
>
>
> def sin(obj):
>     if hasattr(type(obj), '__sin__'):
>         y = type(obj).__sin__()
>         if y is not NotImplemented:
>             return y
>     elif isinstance(obj, numbers.Number):
>         return float.__sin__(float(obj))
>     raise TypeError
>
> Likewise for asin() etc.
>
> Then you could define your own numeric types, such as a Degrees type, a
> PiRadians type, etc, with their own dedicated trig function
> implementations,
> without the caller needing to care about which sin* function they call.
>
>
>
>
> --
> Steve
>
> --
> https://mail.python.org/mailman/listinfo/python-list
>