On Saturday, November 19, 2016 at 4:56:42 PM UTC+1, Maxie Schmidt wrote: > > Hello, > > I have been working back and forth between Sage and Mathematica for a > while now trying to learn how to use Sage to replace Mathematica's core > functionality in my day to day use of it. One of the (sets of) functions > haven't yet found a suitable open source alternative for is related to > guessing formulas and generating functions for an input sequence (as in > Mathematica's FindSequenceFunction and FindGeneratingFunction). Related > functions are Mathematica's RSolve ( > https://reference.wolfram.com/language/ref/RSolve.html?q=RSolve) used to > solve recurrence relations in closed-form formulas, and the closed-source > RISC Sigma package ( > https://www.risc.jku.at/research/combinat/risc/software/Sigma/index.php) > which is able to generate recurrences for many sums and simplify sums > involving harmonic numbers. > > The closest open source alternative I have come across so far is Rubey's > software written in FriCAS described at > http://axiom-wiki.newsynthesis.org/GuessingFormulasForSequences. However, > looking at the source code for the package leaves quite a bit of work to do > to reproduce the output of the Mathematica functions mentioned above. Is > there a better open source alternative to the Mathematica functions > FindSequenceFunction and RSolve that I'm missing in Sage? > > If there isn't a good complete replacement for using Mathematica's > routines for sequence formula guessing and solving recurrences, I'm > interested in trying to write functions / packages that will replace > Mathematica for these tasks. I have already done some work in Sage related > to guessing formulas for special polynomial sequences in my Master's thesis > at UIUC posted at https://arxiv.org/abs/1609.07301. Any suggestions or > links to related open source software are appreciated. > > Open source alternatives to Mathematica would be most welcome.
The ore_algebra package allows guessing holonomic sequences (http://www.risc.jku.at/research/combinat/software/ore_algebra/doc/guessing.html) but there is nothing in Sage for closed forms, Stirling-type sequences or multi-sums as far as I know. Fredrik -- 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.
