Re: standard trig functions for degrees ?

I don't know what exactly Henry wants. If it's just numeric computation,
that's trivial. As he says, it's < 1k of code, which he can write himself.

The hard part is symbolic computation.

I'd think that someone working in degrees would like to see things like:

*sind(x/2),halfangles => sqrt(1-cosd(x))/sqrt(2) *(for 0<x<360)


This gets messier. Yes, you can write pattern matching rules that change
all instances of *cos(...)* to *cosd(...)*, etc.

But what about, say, *limit(sind(x)/x,x,0)*? That gives *%pi/180*; is that
what is expected, or does the user want to see *(%pi/180)°* or maybe *1*?
I've never worked in degrees beyond elementary trig, so I don't know what
the user expects, and whether the system (as opposed to the user) needs to
keep track of degrees vs. radians.

Or am I overthinking it?

          -s

On Mon, Apr 27, 2026 at 4:45 PM Robert Dodier <[email protected]>
wrote:

> On Mon, Apr 27, 2026 at 12:48 PM Henry Baker <[email protected]> wrote:
>
> > A number of computer languages -- e.g., Fortran -- support trig
> functions over degrees -- e.g., sind(x), cosd(x), tand(x), asind(x), etc.
> >
> > I know it's "trivial", but could Maxima please go ahead a define
> standardly the trig functions over degrees?  We're talking about about
> increasing the core system at most by perhaps 1K bytes !
>
> Well, maybe the code is trivial, but the increased mental burden is
> not ... Instead of creating new functions, I am OK with two functions,
> radians(x) to get radians from degrees and degrees(x) to get degrees
> from radians. Then one can call those whenever it makes sense.
>
> We could make those simplifying functions. Just thinking out loud here.
>
> Hmm, maybe degrees(x) should represent x degrees, like radians(x)
> represents x radians. radians(x) simplifies to x and degrees(x)
> simplifies to x*%pi/180. E.g. sin(degrees(90)) --> sin(%pi/2), etc.
>
> I think I'm leaning towards degrees(x) representing x degrees. What
> does anyone else think?
>
> Robert
>
>
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