Have there been any relevant updates since this post? I sometimes have to 
do matrix computations whose entries are polynomials in roots of unity, and 
it would be nice if there were a way to work easily with variables that 
have relations, i.e. in quotients of polynomial rings. Of course, I have no 
idea how hard that sort of thing is to implement, so maybe it's an 
unrealistic hope. The current solution for computations in C[x]/(f) is to 
apply reduce at every step of the calculation with basis f, and I suppose 
that works.


On Tuesday, November 27, 2012 at 11:11:01 AM UTC-8, Aaron Meurer wrote:
>
> Actually, the best you could do with that is to make w**2 automatically 
> return -w - 1. Automatic reduction would be much smarter in the polys. I'm 
> not sure if there's support for it there yet. Unfortunately, the algebraic 
> number support there is still in its infant stage. 
>
> Aaron Meurer
>
> On Nov 27, 2012, at 12:05 PM, Aaron Meurer <[email protected] 
> <javascript:>> wrote:
>
> Oh, I see what you want. No, I don't think we have a RootOfUnity class. 
> You might try to write one, using ImaginaryUnit as your guide, and see how 
> far you can get with it. However, be aware that making stuff auto combine 
> without modifying the core is not easy and is a major problem that we're 
> trying to solve.  
>
> We do have RootOf, which represents an arbitrary algebraic number. 
> Depending on what you want to do with it, it may or may not be enough. 
>
> Aaron Meurer
>
> On Nov 26, 2012, at 10:29 PM, simon <[email protected] <javascript:>> 
> wrote:
>
>
> Thanks Aaron, but that function is actually more complicated than what I 
> am doing now.
>
> Given that we have ImaginaryUnit I thought it might be possible to extend 
> this to
> arbitrary roots of unity, for example.
>
> Cheers,
> Simon.
>
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