This is clever idea. It may be also relatively easy to "separate" this 4 ( or 2in example) variables and then solve 4 recurrence relations directly. But it looks like pure algorithmic, so I would like to ask if someone implement that. Thank You for Your help! K
On Mar 13, 3:36 pm, David Joyner <wdjoy...@gmail.com> wrote: > On Tue, Mar 13, 2012 at 10:27 AM, Kakaz <kazimierz.k...@gmail.com> wrote: > > Thanks for answer. > > > Yes, I did. I found similar question but it was about rsolve and > > second order relation. > > I am looking for rsolve or similar solver in context of several > > variables ( ei. a(n), b(n) in example above and 4 variables in my case > > I want to solve). > > In this case, I would just plug in c1e^(r1n)+c2e^(r2n) (c1, c2 > vectors, r1, r2 complex > numbers/eigenvalues) and use Sage to try to solve. > > > I have read this: > >http://groups.google.com/group/sage-support/browse_thread/thread/a58b... > > and this: > >http://groups.google.com/group/sage-support/browse_thread/thread/6f19... > > I was thinking of this:http://docs.sympy.org/dev/modules/solvers/solvers.html > > > > > > > > > > > On Mar 13, 2:59 pm, David Joyner <wdjoy...@gmail.com> wrote: > >> I think it is in sympy (included in Sage). > > >> I vaguely remember the question has been asked before on > >> this list but I don't remember the exact answer. Did you look through the > >> sage-support archive? > > >> On Tue, Mar 13, 2012 at 9:35 AM, Kakaz <kazimierz.k...@gmail.com> wrote: > >> > Of course it should be: > >> > a(n+1) = A*a(n) + B*b(n) > >> > b(n+1) = C*a(n) + D*b(n) > > >> > On Mar 13, 2:32 pm, Kakaz <kazimierz.k...@gmail.com> wrote: > >> >> Hi all! > >> >> I would like to ask - is there possibility in Sage ( or Maxima) to > >> >> solve first order recurrence relation given by linear system with > >> >> several variables? > >> >> For example: > > >> >> a(n+1) = A*a(n) + B*b(n) > >> >> b(n) = C*a(n) + D*b(n) > > >> >> Have I find solution of linear system at first an then solve > >> >> "separated" relation or is there a possibility to solve such system > >> >> directly? As far as I know - rsolve from sympy - takes only one > >> >> relation as argument. > > >> >> Actually I have such system with 4-variables and rational - constant > >> >> - coefficients ... > >> >> Thanks! > >> >> Kazek Kurz > > >> > -- > >> > To post to this group, send email to sage-support@googlegroups.com > >> > To unsubscribe from this group, send email to > >> > sage-support+unsubscr...@googlegroups.com > >> > For more options, visit this group > >> > athttp://groups.google.com/group/sage-support > >> > URL:http://www.sagemath.org > > > -- > > To post to this group, send email to sage-support@googlegroups.com > > To unsubscribe from this group, send email to > > sage-support+unsubscr...@googlegroups.com > > For more options, visit this group > > athttp://groups.google.com/group/sage-support > > URL:http://www.sagemath.org -- To post to this group, send email to sage-support@googlegroups.com To unsubscribe from this group, send email to sage-support+unsubscr...@googlegroups.com For more options, visit this group at http://groups.google.com/group/sage-support URL: http://www.sagemath.org
