Re: help with equation

[c.]

On 5 Oct 2012, at 08:42, Juan Pablo Carbajal wrote:

> hi,
> You can try the following.
> 
> 0. Are there singularities in the equation?
> 1. Provide a Jacobian.
> 2. Choose a suitable "integration method"' (for example "bdf").
> 3. Try reducing the time step.
> 
> How to do all this is explained in "help lsode" or "doc lsode".
> 
> If everything fails try the Runge-Kutta integrators in the package
> odepkg available from Octave Forge. Remember, providing Jacobian will
> help the integrator produce better solutions if they exist.

If your equation is very stiff you might also want to try the DASPK solver 
instead of LSODE.
All suggestions by JP still hold if you switch to DASPK.
c.