Re: NDSolve is using Solve?
- To: mathgroup at smc.vnet.net
- Subject: [mg117146] Re: NDSolve is using Solve?
- From: Oliver Ruebenkoenig <ruebenko at wolfram.com>
- Date: Thu, 10 Mar 2011 06:14:14 -0500 (EST)
On Wed, 9 Mar 2011, J.Frazer wrote: > Hello everyone, > > This is my first time posting so my apologies if I'm going about this > the wrong way. I'm having the following problem: > > I'm using NDSolve but its not managing to get to the solution even if I > leave it running over the weekend. If I greatly simplify one of the > equations I can get a result but in either case I get the error messages > > Solve:: incnst > Solve:: ifun > > This worries me as if its trying to simplify analytically, presumably as > the equations becomes more complicated this will become incredibly time > consuming. > > Do people agree this may be the cause of the long running time? If so, > is there a way of stopping NDSolve from using Solve? > > Cheers, > > Jonny= > > Hi Jonny, yes NDSolve uses Solve internally but that is only for pre processing purposes. If this is really the cause for the slow NDSolve (maybe it is a hard problem...) It were best if you could send some working code, then we could have a look at it and see if anything can be done. Oliver