Hi, I'm really happy to hear people are giving this code some attention!
I wrote the original FGP package. At the time, there was no support for computing HNF or anything else except for ZZ, so I couldn't even test or try the algorithms there. I **might** have made some assumptions about the base ring being ZZ for simplicity due to this, but I hope I didn't. I don't remember -- it was a long time ago. The only reason this hasn't moved forward after more support for HNF was added for other PIDs is that I'm busy with other things these days. I hope somebody else will take over. If I was working on this code, I would go through the module and add a ton of doctests analogous to the existing tests over ZZ, but over some other PID's. I definitely, definitely would NOT even consider just enabling this functionality with a warning message, and crossing my fingers like Simon seems to be suggestion below. I strongly object to that. I endorse: - enable the functionality - write a bunch of new doctests showing how (and that) it works. - then release it publicly. If it does work, doing the above is maybe 1 day of work. If it doesn't work, so the above is much harder than 1 day of work, then we shouldn't have released it in the first place. Again, Simon, I'm really happy you're looking into this and making this more general functionality available. I was pretty happy with my original FGP implementation, which was a lot of work one summer years ago... -- William On Thu, Oct 12, 2017 at 8:48 AM Simon Brandhorst <[email protected]> wrote: > O.K. I will do that. Even if we do not have enough tests. Maybe we can > allow it and print some > "This code is still experimental" warning. After all it will only get > really stable is people use it a lot. > > On Thursday, October 12, 2017 at 5:06:20 PM UTC+2, Simon Brandhorst wrote: > >> sage: L.<w> = NumberField(x^2 - x + 2) >> sage: OL = L.ring_of_integers() >> sage: V = OL**3; W = V.span([[0,w,0], [1,0,1-w]], OL) >> sage: FGP_Module(V,W) >> This works >> >> sage: V.quotient(W) >> NotImplementedError: quotients of modules over rings other than fields or >> ZZ is not fully implemented >> >> >> Well FGP looks pretty implemented to me. >> >> Objections? >> > -- > You received this message because you are subscribed to the Google Groups > "sage-devel" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to [email protected]. > To post to this group, send email to [email protected]. > Visit this group at https://groups.google.com/group/sage-devel. > For more options, visit https://groups.google.com/d/optout. > -- -- William Stein -- You received this message because you are subscribed to the Google Groups "sage-devel" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. To post to this group, send email to [email protected]. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
