NDSolve precision and velocity problem

*To*: mathgroup at smc.vnet.net*Subject*: [mg91295] NDSolve precision and velocity problem*From*: Joerg Schaber <schaber at molgen.mpg.de>*Date*: Thu, 14 Aug 2008 06:58:15 -0400 (EDT)

Hi, I have an ODE system that takes lots of time to solve with NDSolve (several minutes), whereas the same system with the FORTRAN solver LSODA solves the problem in an second. When I decrease the precision, e.g. AccuracyGoal->6, NDSolve crashes. It often crashes, because it finds complex values in a less-than-comparison. Maybe it's a method problem. How do I tell NDSolve, to use the same methods as the LSODEA solver? Thanks, joerg