Re: NDSolve (loop)
- To: mathgroup at smc.vnet.net
- Subject: [mg116996] Re: NDSolve (loop)
- From: greg28 <grega.smrkolj at gmail.com>
- Date: Mon, 7 Mar 2011 05:47:03 -0500 (EST)
Hi, let me be more specific about my problem. My code in mathematica is: _______________________________________ T=1000 (truncation of time, assuming that V(s,x)-> V(x) as T-> infinity) alpha= 0.1 pde= some complicated expression (involving 1st and 2nd order derivatives) soln = NDSolve[{pde, V[0, x] == 0, V[s, xu] == 0, (D[V[s, x], x] /. x -> xd) == 0}, V[s, x], {s, 0, T}, {x, xd, xu}, Method -> {"MethodOfLines", "SpatialDiscretization" -> {"TensorProductGrid", "MinPoints" -> 1000}} ] _______________________________________ This is then a particular solution for alpha=0.1. However, my problem is to find a value of alpha, at which, for instance, V[x=0.3]=alpha/2. So I need to write a loop which will stop when this condition is satisfied. The problem is that one evaluation takes a lot of time, so I wonder whether it is somehow possible to speed up NDSolve, e.g. by somehow telling mathematica what the solution for alpha=0.1 was when solving for alpha=0.2 or something like this. The shape of V should not differ too much between alpha=0.1 and alpha=0.2...