# [ODE] what integration method is used ?

**nlin@nlin.net
**
nlin at nlin.net

*Mon Nov 18 03:35:02 2002*

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