I was looking at polynomial remainder sequence related parts of FriCAS, and I find there are some improvement space.
I'll use PRS for "polynomial remainder sequence", not to be confused with package PseudoRemainderSequence. 1. PRS parts in FriCAS: package PRS in prs.spad by Ducos Lionel package SUBRESP in intrf.spad by Barry Trager and Renaud Rioboo package SHP in sturm.spad by Lalo Gonzalez-Vega package POLUTIL in reclos.spad by Renaud Rioboo wrappers in poly.spad and newpoly.spad They weren't updated for at least 10 years, probably over 20 years. 2. improvements I can think of: 2.1 package PRS in prs.spad is pretty good. 2.2 SUBRESP is an ugly wrapper for chainSubResultants$PRS, see the comments in intrf.spad. Maybe we can enhance chainSubResultants$PRS and remove SUBRESP. (and I think SUBRESP has a bug) 2.3 I think SHP reinvented the wheel: subresultantSequence$SHP should be replaced by chainSubResultants$PRS. 2.4 POLUTIL reinvented the wheel of SHP: they try to do the same thing (find real root), but POLUTIL is inefficient and less advanced, however SHP currently contains bugs. This will be a pretty big change, so I want to hear your opinions first. (I've done some basic cleaning up, haven't done big changes yet). -- You received this message because you are subscribed to the Google Groups "FriCAS - computer algebra system" group. To unsubscribe from this group and stop receiving emails from it, send an email to fricas-devel+unsubscr...@googlegroups.com. To post to this group, send email to fricas-devel@googlegroups.com. Visit this group at https://groups.google.com/group/fricas-devel. For more options, visit https://groups.google.com/d/optout.
