void ParGridFunction::ComputeFlux(
BilinearFormIntegrator &blfi,
GridFunction &flux, int wcoef, int subdomain)
{
ParFiniteElementSpace *ffes =
dynamic_cast<ParFiniteElementSpace*>(flux.FESpace());
MFEM_VERIFY(ffes, "the flux FE space must be ParFiniteElementSpace");
Array<int> count(flux.Size());
SumFluxAndCount(blfi, flux, count, wcoef, subdomain);
// Accumulate flux and counts in parallel
ffes->GroupComm().Reduce<double>(flux, GroupCommunicator::Sum);
ffes->GroupComm().Bcast<double>(flux);
ffes->GroupComm().Reduce<int>(count, GroupCommunicator::Sum);
ffes->GroupComm().Bcast<int>(count);
// complete averaging
for (int i = 0; i < count.Size(); i++)
{
if (count[i] != 0) { flux(i) /= count[i]; }
}
if (ffes->Nonconforming())
{
// On a partially conforming flux space, project on the conforming space.
// Using this code may lead to worse refinements in ex6, so we do not use
// it by default.
// Vector conf_flux;
// flux.ConformingProject(conf_flux);
// flux.ConformingProlongate(conf_flux);
}
}
