def resolve(self, subproblemcontext, existingStepper):
# Return a new AdaptiveDriver object (not a Basic one)
# appropriate for the given subproblem. If the
# existingStepper is still appropriate, return it instead.
from ooflib.engine import twostep
from ooflib.SWIG.engine import steperrorscaling
if subproblemcontext.second_order_fields():
from ooflib.engine import ss22
if (isinstance(existingStepper, AdaptiveDriver)
and isinstance(existingStepper.stepper, twostep.TwoStep)
and isinstance(existingStepper.stepper.singlestep,
ss22.SS22)):
return existingStepper
singlestep = ss22.SS22(theta1=0.5, theta2=0.5)
else: # no second order fields
from ooflib.engine import euler
if (isinstance(existingStepper, AdaptiveDriver)
and isinstance(existingStepper.stepper, twostep.TwoStep)
and isinstance(existingStepper.stepper.singlestep,
euler.CrankNicolson)):
return existingStepper
singlestep = euler.CrankNicolson()
return AdaptiveDriver(
stepper=twostep.TwoStep(singlestep),
tolerance=self.tolerance,
errorscaling=steperrorscaling.AbsoluteErrorScaling(),
initialstep=0.0,
minstep=self.minstep)
def resolve(self, subproblemcontext, existingStepper):
# Return a new UniformDriver object (not a Basic one)
# appropriate for the given subproblem. If the
# existingStepper is still appropriate, return it instead.
if subproblemcontext.second_order_fields():
from ooflib.engine import ss22
if (isinstance(existingStepper, UniformDriver)
and isinstance(existingStepper.stepper, ss22.SS22)):
return existingStepper
return UniformDriver(stepper=ss22.SS22(theta1=0.5, theta2=0.5),
stepsize=self.stepsize)
else:
from ooflib.engine import euler
if (isinstance(existingStepper, UniformDriver) and isinstance(
existingStepper.stepper, euler.CrankNicolson)):
return existingStepper
return UniformDriver(stepper=euler.CrankNicolson(),
stepsize=self.stepsize)