Speedup Partial Differential Equation Solver

Hi,

we are using the Partial Differential Equation Toolbox so solve a 2D System with 2 equations. The solving procedure takes virtually forever because the solver evaluates a lot of time points. How can I get the solver to be less accurate and therefore evaluate fewer time points? I tried changing the SolverOptions from the PDEModel but I can not notice any significant effect regardless of the settings is set.

Best regards Andreas

Answer 1

[Alan Weiss]

There are two possible sets of time points that the solver visits. One is the set in tlist, the points you tell the solver to compute. The others are out of your control, they are the points that the internally-called ode15s decides to compute. If ode15s is visiting a lot of points, it is because your problem requires it due to stiffness, fast changes, or the like.

You say that you have relaxed the tolerances, presumably AbsoluteTolerance, RelativeTolerance, and/or ResidualTolerance. You might also want to set the ReportStatistics option to 'on' to see exactly how ode15s is struggling.

So, sorry, I don't have any good ideas for you. Some problems are just not simple to solve.

Alan Weiss

MATLAB mathematical toolbox documentation