Matching against identities can be valuable. Writing out several variations for a intended single pattern feels like a hack.
Or at least, that was my experience with my matrix expressions system. I wasn't able to cleanly add in identities so I shoved in lots more patterns. Things worked. The prototype <https://github.com/mrocklin/matrix-algebra>, written in Maude, supported identities. I found this pleasant (though reimplementing Maude seems hard). On Sat, Nov 29, 2014 at 2:57 PM, Joachim Durchholz <j...@durchholz.org> wrote: > Am 29.11.2014 um 18:52 schrieb James Crist: > >> The system described in the Jenks paper would work better than what I've >> written if we plan to use relatively small sets of small patterns. Larger >> patterns, or larger rulesets will work better with what I'm writing, (I >> think), as they will have more potential paths, and generating specialized >> predicates for each path will get increasingly expensive. >> > > If you're after how a "standard" set of patterns might look like, Rubi > might be a good start. > See http://www.apmaths.uwo.ca/~arich/ . > > It's several thousand rules. > IIRC, they have been carefully constructed to be non-overlapping (you can > only apply a single rule at any time), so they might be "too easy" to > really test the algorithm's design. > > -- > You received this message because you are subscribed to the Google Groups > "sympy" group. > To unsubscribe from this group and stop receiving emails from it, send an > email to sympy+unsubscr...@googlegroups.com. > To post to this group, send email to sympy@googlegroups.com. > Visit this group at http://groups.google.com/group/sympy. > To view this discussion on the web visit https://groups.google.com/d/ > msgid/sympy/547A4F57.6050902%40durchholz.org. > > For more options, visit https://groups.google.com/d/optout. > -- You received this message because you are subscribed to the Google Groups "sympy" group. To unsubscribe from this group and stop receiving emails from it, send an email to sympy+unsubscr...@googlegroups.com. To post to this group, send email to sympy@googlegroups.com. Visit this group at http://groups.google.com/group/sympy. To view this discussion on the web visit https://groups.google.com/d/msgid/sympy/CAJ8oX-ETMvEqcDzR2H6zseeQidJP7BkCL1Lyk_5WADttYxEFYA%40mail.gmail.com. For more options, visit https://groups.google.com/d/optout.
