57 lines
1.9 KiB
C++
57 lines
1.9 KiB
C++
module;
|
|
#include "mean_field.h"
|
|
#include <array>
|
|
|
|
module mean_field;
|
|
|
|
namespace mean_field::physics {
|
|
double compute_moment_of_inertia(
|
|
const fem::FEM &fem,
|
|
const mfem::GridFunction &rho_ref
|
|
) {
|
|
double local_I = 0.0;
|
|
|
|
for (int i = 0; i < fem.mesh->GetNE(); i++) {
|
|
if (fem.mesh->GetAttribute(i) == 3)
|
|
continue;
|
|
|
|
mfem::ElementTransformation *T =
|
|
fem.mesh->GetElementTransformation(i);
|
|
using DensityField = field::Field<field::Density>;
|
|
const quadrature::Query query =
|
|
DensityField::make_query<field::Density::Form::Quadrupole>(
|
|
quadrature::QuadratureRole::diagnostic, T->OrderW(),
|
|
std::array<int, 1>{2}, utils::DOMAINS::STELLAR,
|
|
quadrature::MappingKind::general
|
|
);
|
|
const mfem::IntegrationRule &ir =
|
|
*fem.quadratureFactory->get(query, T->GetGeometryType())
|
|
.integration_rule;
|
|
|
|
for (int j = 0; j < ir.GetNPoints(); j++) {
|
|
const mfem::IntegrationPoint &ip = ir.IntPoint(j);
|
|
T->SetIntPoint(&ip);
|
|
|
|
const double rho_hat = rho_ref.GetValue(i, ip);
|
|
|
|
mfem::Vector x_phys;
|
|
fem.mapping->GetPhysicalPoint(*T, ip, x_phys);
|
|
|
|
const double r_cyl_sq =
|
|
x_phys(0) * x_phys(0) + x_phys(1) * x_phys(1);
|
|
const double detJ = std::fabs(fem.mapping->ComputeDetJ(*T, ip));
|
|
const double weight = T->Weight() * ip.weight * detJ;
|
|
|
|
local_I += rho_hat * r_cyl_sq * weight;
|
|
}
|
|
}
|
|
|
|
double global_I = 0.0;
|
|
MPI_Allreduce(
|
|
&local_I, &global_I, 1, MPI_DOUBLE, MPI_SUM, fem.mesh->GetComm()
|
|
);
|
|
|
|
return global_I;
|
|
}
|
|
} // namespace mean_field::physics
|