You can not select more than 25 topics
Topics must start with a letter or number, can include dashes ('-') and can be up to 35 characters long.
50 lines
1.8 KiB
50 lines
1.8 KiB
#include <medusa/Medusa_fwd.hpp>
|
|
#include <Eigen/SparseCore>
|
|
#include <Eigen/IterativeLinearSolvers>
|
|
|
|
/// Medusa example of loading a pre-prepared domain that can be imported and solved with medusa.
|
|
/// As long as a hdf5 file is available that contains the positions, types, normals and a
|
|
/// boundary map between normals and types this can be done.
|
|
/// http://e6.ijs.si/medusa/wiki/index.php/Poisson%27s_equation
|
|
|
|
using namespace mm; // NOLINT
|
|
|
|
int main() {
|
|
// Import domain from h5 file
|
|
HDF hdf("triceratops_domain.h5");
|
|
DomainDiscretization<Vec3d> domain = DomainDiscretization<Vec3d>::load(hdf, "/domain");
|
|
hdf.close();
|
|
|
|
// Find support for the nodes
|
|
int N = domain.size();
|
|
domain.findSupport(FindClosest(15)); // the support for each node is the closest 9 nodes
|
|
|
|
// Construct the approximation engine, in this case a weighted least squares using Gaussians
|
|
// as basis functions, no weight, and scale to farthest
|
|
WLS<Gaussians<Vec3d>, NoWeight<Vec3d>, ScaleToFarthest> wls({15, 50.0});
|
|
|
|
auto storage = domain.computeShapes<sh::lap>(wls); // compute the shapes using our WLS
|
|
|
|
Eigen::SparseMatrix<double, Eigen::RowMajor> M(N, N);
|
|
Eigen::VectorXd rhs(N); rhs.setZero();
|
|
|
|
auto op = storage.implicitOperators(M, rhs); // construct implicit operators over our storage
|
|
M.reserve(storage.supportSizes());
|
|
for (int i : domain.interior()) {
|
|
op.lap(i) = -1;
|
|
}
|
|
for (int i : domain.boundary()) {
|
|
op.value(i) = 0.0;
|
|
}
|
|
|
|
Eigen::BiCGSTAB<decltype(M), Eigen::IncompleteLUT<double>> solver;
|
|
solver.compute(M);
|
|
ScalarFieldd u = solver.solve(rhs); // solve the system
|
|
|
|
// Write the solution into file
|
|
HDF out("triceratops.h5", HDF::DESTROY);
|
|
out.writeDoubleArray("solution", u);
|
|
out.close();
|
|
|
|
return 0;
|
|
}
|
|
|