trigonometric simplification



More choices:

* Reduce floats/bfloats?  Should cos(x+234.234) => cos(x + 1.75...)?
* I'd think reducing other constants is unnecessary, e.g. sin(234/5) =>
sin(234/5-14*%pi) or sin(%e^2) => sin(%e^2-2*%pi) -- when are such things
useful/meaningful? and anyway, Maxima by default (%piargs:true) eliminates
the syntactical multiples of %pi.

           -s

On Thu, Jan 24, 2013 at 11:07 AM, Stavros Macrakis <macrakis at alum.mit.edu>wrote:

> Yes, there are several choices to be made:
>
> * What range to reduce to?  For sin, I'd think -%pi/2 .. %pi/2; for cos, 0
> .. %pi.
> * Prefer -sin(...) or sin(-x)?  (Maxima currently prefers the former)
> * Reduce everything to cos instead of mixed sin/cos?  (or everything to
> sin)
>
> Opinions?
>
>         -s
>
>
> On Thu, Jan 24, 2013 at 10:47 AM, Steve Haflich <smh at franz.com> wrote:
>
>> Stavros Macrakis <macrakis at alum.mit.edu> wrote:
>>
>>    I'd think that Maxima should do range reductions like cos(23/5*%pi) =>
>> cos(3/5*%pi) by default, and even for that matter cos
>>    (x+23/5*%pi) => cos(x+3/5*%pi).  Perhaps do this with %piargs='all and
>> make that the default?
>>
>> You should clarify what what you intend for negative angels:
>>
>>   cos(-23/5*%pi) => cos(2/5*%pi) ???
>>
>> While this isn't a very problematic issue, it ought be specified.  cos
>> is symmetric about zero, but this property is more evident if the domain
>> were reduced to -pi..+pi instead.  Would this matter anywhere?
>>
>
>