On Saturday, 15 December 2018 18:19:53 UTC+1, parisse wrote: > > Bill, my feeling is that part of ODK money was used to improve > multivariate polynomial arithmetic implementations precisely in a domain > where Giac behaves well (and maybe I should emphasize that unlike almost > all other CAS, Giac is a library, i.e. is interoperable with any software > that can interact with a C++ library). Despite that, ODK ignores Giac. >
I'm really puzzled by this. There is even overlap *within* ODK. Our local site and another colleague of ours also contributed to parallel root clustering, a superoptimiser, a Jupyter interface, SIMD optimisation, a quadratic sieve and so on. I think Giac barely covers any of that. We aren't trying to do multivariate arithmetic; we are trying to improve and modernise the system that we have been developing for 30 years in the direction of HPC, and expose it to a VRE so that it can be a more useful tool in the "toolbox". Giac does not address that for us. But even if we just focus on multivariate arithmetic (which we obviously need, just as you do), the new implementation we are working on seems to have different goals: * lex, deglex, degrevlex (and soon, weighted) orderings in an arbitrary number of variables * multiprecision exponents (to support new algorithms for sparse interpolation) * near linear scaling of all major algorithms up to many cores with a highly optimised threaded memory manager * fast specialised multivariate arithmetic and gcd over Z/pZ, Z and Q (and some initial work over finite fields and extensions insofar as it is necessary for the other) * ideal reduction * specialised cases for dense, quasi-sparse and sparse algorithms * integration with Singular via Factory (the library of Singular that does multivariate arithmetic for applications other than GBs) * exposure to a VRE * clear, modularised code, documentation and tests It's not clear to me how much of all that giac supports. And I am sure I've mentioned most of these goals, both publicly and privately. I apologise if I have not made this more clear in the past. It is certainly not our goal to just do what giac already does. And even if giac did all that, it is one of many projects doing multivariate polynomial arithmetic in Europe. There's also Trip, Piranha, Factory, Pari/GP, Gap. I really don't think it is a valid argument that just because your CAS/library can do multivariate arithmetic that we should stop working on it! Also, I don't believe we've ignored giac at all. I've sent dozens of emails to you personally. I've mentioned your work to many of my colleagues, and when we benchmark our stuff, I have benchmarked giac, and been in contact with you personally when we do. I vaguely recall inviting you for a visit once. Surely, I am missing your point here. Well, I'm not sure it's the right place to discuss that, and anyway past is > the past. > Now that I made the effort to fine tune my gbasis code, it behaves very > well on Q on multi-CPUs architectures. We'll see if there is more interest > or not. > Great. I will mention this to my colleagues next door, who are working on GB's. I am sure they will be very interested to hear about and compare the progress you have made. -- 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 sage-devel+unsubscr...@googlegroups.com. To post to this group, send email to sage-devel@googlegroups.com. Visit this group at https://groups.google.com/group/sage-devel. For more options, visit https://groups.google.com/d/optout.
