NDSolve: ..numerically ill-conditioned...
- To: mathgroup at smc.vnet.net
- Subject: [mg109474] NDSolve: ..numerically ill-conditioned...
- From: Alessio Giberti <giberti at fe.infn.it>
- Date: Wed, 28 Apr 2010 07:00:07 -0400 (EDT)
I have to solve numerically equations like u''[x] - 1*^7 u[x] == 3.6*^7, u'[0]==0, u'[2*^-3]==0, but I get the message: "The equations derived from the boundary conditions are numerically ill-conditioned. The boundary conditions may not be sufficient to uniquely define a solution. The computed solution may match the boundary conditions poorly." No problem with less extreme coefficients, the solutions are good, but more extreme coefficients lead to non-reliable results. What can I do to overcome the problem?