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how to NDSolve x'[t] == 1 where x[t] -> Mod[x,2*Pi] ?

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  • Subject: [mg7172] how to NDSolve x'[t] == 1 where x[t] -> Mod[x,2*Pi] ?
  • From: calvitti at glenn.ces.cwru.edu
  • Date: Tue, 13 May 1997 01:58:11 -0400 (EDT)
  • Organization: Case Western Reserve University
  • Sender: owner-wri-mathgroup at wolfram.com

i'm intersted in integrating ODEs (or systems of 1st order ODEs) that
represent phase dynamics (oscillators) and therefore evolve on
tori. i.e. the state has to be taken modulo 2 Pi whenever it 'leaves'
the range [0,2*PI]?  the simplest example is:

x'[t] == 1  where x[t] -> Mod[x , 2 Pi] 

in general x'[t] == f[x] where f[x] is 2*Pi periodic in all its
arguements defines a smooth dynamical system on an n-torus

how can i force NDSolve to take the modulo of the dependent states?

thanks for the info,

 +---------------------------------+
 |          Alan Calvitti          |
 |       Control Engineering       |
 | Case Western Reserve University |
 +---------------------------------+


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