OOF2: The Manual


Adaptive (BasicAdaptiveDriver) — Take variable sized time steps.




  • Base class: BasicStepDriver
  • Parameters:

    Maximum permissable error. Type: A real number.
    Minimum time step size. Type: A real number.


Using BasicAdaptiveDriver as the time_stepper in BasicSolverMode tells OOF2 to solve a time dependent problem using adaptive stepping, in which the step size is adjusted to keep the estimated error below the given tolerance. If that is not possible without using timesteps smaller than minstep, an error will be raised and the calculation will be aborted.

Adaptive stepping requires more computation per step than uniform stepping, but can be much more accurate and efficient, especially if the optimal step size changes during a calculation.

BasicAdaptiveDriver automatically uses the SS22 method with theta1=theta2=0.5 if the equations contain second order time derivatives. It uses CrankNicolson otherwise. In both cases, the time step control and error estimation are handled by TwoStep and AbsoluteErrorScaling.

AdaptiveDriver plays the same role in AdvancedSolverMode that BasicAdaptiveDriver plays in BasicSolverMode.