Comment #8 on issue 1562 by asmeurer: Have trigsimp apply factor and Poly.cancel() to sin's and cos's http://code.google.com/p/sympy/issues/detail?id=1562
> Don't worry, I'm interested in working on this. Glad to hear it! I realized that we never created an issue for that general RootOf idea, so I created one. See issue 1579. For now, I am using the very simple RootOf class that does exist, because I would rather return n solutions to a nth order linear differential equation with constant coefficients with RootOfs than return only the hand full that SymPy can find. Hopefully someday you will at least be able to call evalf on them to get a numerical solution. And yes, Poly args is kind of a mess. It is the only class in SymPy that I know of that fails expr == expr.new(*expr.args()) (there is some __getnewargs__ method in Poly that will convert the args to a way that will work, but I don't know how it is supposed to be used). I think this that expr.args should be whatever makes expr == expr.new(*expr.args()) always true, because sometimes it is nice to use that hack. Also, Poly args use tuples and Python ints, like you said, which most functions that look at args do not expect. It can be a problem for functions that look at args recursively with things like RootOf that have Poly's in their args (like with issue 1563). I think the solution here is to just avoid putting Poly() in the args of anything that the user would use, like RootOf, because it can cause problems. It isn't as big of a deal if these things don't work with Poly() itself, because it is just an internal thing like you said. By the way Mateusz, have you seen my issue 1555? I probably should have CC'd you on it. -- You received this message because you are listed in the owner or CC fields of this issue, or because you starred this issue. You may adjust your issue notification preferences at: http://code.google.com/hosting/settings --~--~---------~--~----~------------~-------~--~----~ You received this message because you are subscribed to the Google Groups "sympy-issues" group. To post to this group, send email to sympy-issues@googlegroups.com To unsubscribe from this group, send email to sympy-issues+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sympy-issues?hl=en -~----------~----~----~----~------~----~------~--~---
