Re: lsode -- a do-it-all DGL solver?

[John W. Eaton]

On  9-Aug-2007, Matthias Brennwald wrote:

| Thanks for this pointer. I am however unsure whether
|   (i) lsode analyzes the differential equation to determine if the
| equation is stiff or non-stiff, or 
|   (ii)  the user has to tell lsode about the stiffness of the equation.
| 
| Is it (i) or (ii)?

Neither?

LSODE uses the method you select.  By default, Octave tells LSODE to
use a backward differentiation formula method which was designed for
solving stiff sets of equations but it also works fine for non-stiff
systems.

jwe