[ODE] what integration method is used ?

[nlin@nlin.net]

Nguyen Binh <ngbinh at glassegg.com> wrote:
> On Fri, Nov 15, 2002 at 02:28:59PM +0100, Torsten Hans wrote:
> TH> what basic integration scheme does ODE use ? is it an
> TH> explicit or implicit integration method ? does it use
> TH> runge kutta or something else ?
> 
> Refer to the 0.3 docs, you'll see that ODE curently use basic Euler
> integration.

Not quite. Somewhere in the docs is mentioned that ODE uses a
_time_ _stepping_ Euler integration scheme. This is a bit more hairy
to extend to higher order schemes. For the gory details and some
links to research papers see the thread started in April 2002 at

http://q12.org/pipermail/ode/2002-April/001175.html

> TH> is it possible to use a different integration scheme ?
> Sure, But maybe you'll have to do it yourself or waiting for future
> ODE release.

A discussion on this topic in March 2002:

nlin> The problem with all of this ... is the interplay of all of this
nlin> with the time-stepping scheme.

russ>actually i'm not sure what a higher order time stepping scheme
russ>will look like in this case. i'd have to sit down and read some
russ>papers and write some equations. it's not a problem i have
russ>considered yet.

Don't let this stop you - I'd also be interested in seeing the performance
and accuracy of higher-order integration schemes with ODE - but be aware
that this isn't a completely trivial thing to do because of the time-stepping
(rather than instantaneous) view of the equations to be solved.

-Norman