Re: Poincare section for double pendulum
- To: mathgroup at smc.vnet.net
- Subject: [mg120664] Re: Poincare section for double pendulum
- From: JUN <noeckel at gmail.com>
- Date: Wed, 3 Aug 2011 07:05:22 -0400 (EDT)
- Delivered-to: l-mathgroup@mail-archive0.wolfram.com
- References: <j10l10$osi$1@smc.vnet.net>
On Jul 30, 3:05 am, "Christoph Lhotka" <christoph.lho... at univie.ac.at> wrote: > Hello, > > this is just a starting point... > > Try to solve your problem with the method "EventLocator" in NDSolve to > limit your output to values on the Poincar=E9 surface of section. > You could use e.g. FindInstance to get a good set of initial conditions > for given energy value of the Hamiltonian. > > Good luck, > > Christoph Yes, the chapter tutorial/NDSolveEventLocator in the help browser is definitely worth reading (in particular the section about the Henon-Heiles system)! My simpler approach could give you duplicate zeros of x[t] -- which doesn't matter for the Poincare section (and could be fixed by DeleteDuplicates). However, EventLocator is a cleaner solution. Jens