Re: Graphing the Separatix

*To*: mathgroup at smc.vnet.net*Subject*: [mg81998] Re: Graphing the Separatix*From*: Jens-Peer Kuska <kuska at informatik.uni-leipzig.de>*Date*: Tue, 9 Oct 2007 05:34:17 -0400 (EDT)*Organization*: Uni Leipzig*References*: <fea9pk$k80$1@smc.vnet.net>*Reply-to*: kuska at informatik.uni-leipzig.de

Hi, the curvature of the field lines has a zero along the separatrix in this case. To get curved lines you have to compute the field lines by integrating the equations for the vector field. Regards Jens DBK wrote: > I am plotting the vector fields for the two equation system below > using version 6. I have two questions. > 1. How do I plot the separatix (i.e. stable manifold) separating the > two basins of attraction? > 2. How do I show the dynamics of the system with curved rather than > straight vectors? > > Needs["VectorFieldPlots`"]; > p1 = 0.28; > p2 = 0.7; > p3 = 0.8; > p4 = 0.15; > p5 = 0.7; > p6 = 0.6; > p7 = 6.5; > p8 = 0.3; > aah = 0.00003333; > fields = (VectorFieldPlot[{(p1 a (p2 - a - p3 c))/p2, ( > p4 c (p5 - c - (p6 a^p7)/(a^p7 + p8^p7)))/p5}, {a, 0, 1}, {c, 0, > 1}, PlotPoints -> 10, ScaleFactor -> None, Axes -> Automatic, > MaxArrowLength -> 1, VectorHeads -> True]) > >