[SciPy-user] nullclines for nonlinear ODEs

[John Hunter]

On 10/30/07, John Hunter <jdh2358 at gmail.com> wrote:
> In a workshop on scientific computing in python  I ran with Andrew
> Straw last weekend at the Claremont Colleges, I presented a unit on
> ODEs, numerically integrating the Lotka-Volterra equations, drawing a
> direction field, plotting a trajectory in the  phase plane, and
> plotting the nullclines.  For the nullclines, I used matplotlib's
> contouring routine with levels=[0], but I was wondering if there was a
> better/more direct route.

I should add, of course for the Lotka-Volterra equations one can
easily do this analytically, but I was trying to illustrate a general
approach for equations in which one could not necessarily write
analytic expressions for the nullclines.

JDH