Rubi should rather be seen as a useful collection of knowledge that can be implemented in different ways. I encourage the Maxima authors to e.g. have a look at Rubi's chapter 1.2.1. They seem to have completely missed that the integral of (a+bx+cx^2)^p, p rational, has a general solution in terms of 2F1.
On Mon, Feb 27, 2017, 18:13 Emmanuel Charpentier < emanuel.charpent...@gmail.com> wrote: > A few points : > > 1. Sympy has interesting answers in some cases. But : > 1. It often offers responses as conditional expressions (akin to > Mathematica's lists of tuples (expression, rule)), whic we don't (yet ?) > know how to handle ; > 2. It often uses special functions not (yet ?) implemented in Sage. > 3. The current sympy integration routines tend to drop into (what > seems to be) infinite loops, nort returning after long times (many > minutes). > 2. Fricas has been mentioned as an interesting subcase, since its > implementation is (supposed to) find any primitive using only "elementary" > functions (polynoms, log/exp/trig) if such a primitive exists. > 3. ISTR that porting Rubi to Sage has been proposed as a GSOC project > a couple of years back, but that one of the conclusions was that: > 1. This intensely used pattern-matching, not really compatible with > Maxima's abilities, whose implementation was a non-trivial task in > itself. > 2. No suitable couple of (mentor - trainee) emerged of the process. > > Nevertheless, implementing Rubi is probably a good idea. I wonder if a > specialized pattern matcher woldn't be a better idear than monkeying > Mathematica's. ISTR to have toyed with RJF's suggestion of extending hois Mo > > -- > You received this message because you are subscribed to a topic in the > Google Groups "sage-devel" group. > To unsubscribe from this topic, visit > https://groups.google.com/d/topic/sage-devel/7OO_VyMC1Ts/unsubscribe. > To unsubscribe from this group and all its topics, 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. > -- 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.
