Why does using the Partial Differential Equation (PDE) Toolbox result in the error: step size too small ?
14 views (last 30 days)
Show older comments
When using the Partial Differential Equation (PDE) Toolbox, I get the following error:
step size too small.
Accepted Answer
MathWorks Support Team
on 18 Dec 2012
When you get the error "step size too small", you can try the following to resolve it:
1. Try using a "lumped" of full Jacobian instead of the fixed one, which is the default. The Jacobian approximation method is selected in the Solve Parameters dialog box, which you open by selecting Parameters... from the Solve menu. Often, using the full or "lumped" Jacobian helps to achieve convergence at the cost of some extra computations. In this case, the "lumped" Jacobian works; the full Jacobian fails due to a singularity.
2. Specify a suitable initial solution. A good guess of what the soultion will look like can be used as a starting point for the nonlinear solver. The initial value can also be entered in the Solve Parameters dialog box. If you don't specify an initial solution, zero is used as the default.
0 Comments
More Answers (0)
See Also
Categories
Find more on PDE Solvers in Help Center and File Exchange
Community Treasure Hunt
Find the treasures in MATLAB Central and discover how the community can help you!
Start Hunting!