[sage-support] Re: Difference equations?
On Sat, May 30, 2009 at 5:13 PM, Alasdair amc...@gmail.com wrote: I can solve a difference equation using the Maxima interface, and the solve_rec package included with Maxima. Apparently SymPy can also solve difference equations, but I can't find any documentation or examples to show how this is done. So, two questions: 1) How can difference equations be solved using SymPy, from within Sage? You might consider posting the above question to the sympy mailing list: http://groups.google.com/group/sympy 2) Is it possible to write a little bit of code which will provide a difference equation solver for Sage, using Maxima's solve_rec package to perform the actual calculation? Thanks, Alasdair -- William Stein Associate Professor of Mathematics University of Washington http://wstein.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 URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Difference equations?
Alasdair wrote: I can solve a difference equation using the Maxima interface, and the solve_rec package included with Maxima. Apparently SymPy can also solve difference equations, but I can't find any documentation or examples to show how this is done. So, two questions: 1) How can difference equations be solved using SymPy, from within Sage? 2) Is it possible to write a little bit of code which will provide a difference equation solver for Sage, using Maxima's solve_rec package to perform the actual calculation? Can you give an example in maxima of using the solve_rec command? Jason --~--~-~--~~~---~--~~ 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 URLs: http://www.sagemath.org -~--~~~~--~~--~--~---
[sage-support] Re: Difference equations?
You use solve_rec like this:
maxima.load('solve_rec')
maxima('solve_rec(f[n+2]-3*f[n+1]+2*f[n]=2^n,f[n],f[0]=1,f[1]=0)')
I think that solve_rec can in fact solve a larger class of difference
equations than linear equations with constant coefficients, but my
use doesn't involve anything more that this.
-Alasdair
On May 31, 11:22 am, Jason Grout jason-s...@creativetrax.com wrote:
Alasdair wrote:
I can solve a difference equation using the Maxima interface, and the
solve_rec package included with Maxima. Apparently SymPy can also
solve difference equations, but I can't find any documentation or
examples to show how this is done. So, two questions:
1) How can difference equations be solved using SymPy, from within
Sage?
2) Is it possible to write a little bit of code which will provide a
difference equation solver for Sage, using Maxima's solve_rec package
to perform the actual calculation?
Can you give an example in maxima of using the solve_rec command?
Jason
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[sage-support] Re: Difference equations?
On Sat, May 30, 2009 at 10:50 PM, Alasdair amc...@gmail.com wrote:
You use solve_rec like this:
maxima.load('solve_rec')
maxima('solve_rec(f[n+2]-3*f[n+1]+2*f[n]=2^n,f[n],f[0]=1,f[1]=0)')
Also, see
http://maxima.sourceforge.net/docs/tutorial/en/gaertner-tutorial-revision/Pages/DiffEq0001.htm
This might be related to
http://trac.sagemath.org/sage_trac/ticket/1291
(which I found using google) but trac is down now so I can't be sure.
I think that solve_rec can in fact solve a larger class of difference
equations than linear equations with constant coefficients, but my
use doesn't involve anything more that this.
-Alasdair
On May 31, 11:22 am, Jason Grout jason-s...@creativetrax.com wrote:
Alasdair wrote:
I can solve a difference equation using the Maxima interface, and the
solve_rec package included with Maxima. Apparently SymPy can also
solve difference equations, but I can't find any documentation or
examples to show how this is done. So, two questions:
1) How can difference equations be solved using SymPy, from within
Sage?
2) Is it possible to write a little bit of code which will provide a
difference equation solver for Sage, using Maxima's solve_rec package
to perform the actual calculation?
Can you give an example in maxima of using the solve_rec command?
Jason
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