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mfem/examples/pumi/ex6p.cpp
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// MFEM Example 6 - Parallel Version
// PUMI Modification
//
// Compile with: make ex6p
//
// Sample runs: mpirun -np 8 ex6p
//
// Description: This is a version of Example 1 with a simple adaptive mesh
// refinement loop. The problem being solved is again the Poisson
// equation -Delta u = 1 with homogeneous Dirichlet boundary
// conditions. The problem is solved on a sequence of meshes which
// are adapted in a conforming (tetrahedrons) manner according
// to a simple SPR ZZ error estimator.
//
// This PUMI variation also performs a "uniform" refinement,
// similar to MFEM examples, for coarse meshes. However, the
// refinement is performed using the PUMI API. A new option "-ar"
// is added to modify the "adapt_ratio" which is the fraction of
// allowable error that scales the output size field of the error
// estimator.
//
// NOTE: Model/Mesh files for this example are in the (large) data file
// repository of MFEM here https://github.com/mfem/data under the
// folder named "pumi", which consists of the following sub-folders:
// a) geom --> model files
// b) parallel --> parallel pumi mesh files
// c) serial --> serial pumi mesh files
#include "mfem.hpp"
#include <fstream>
#include <iostream>
#ifdef MFEM_USE_SIMMETRIX
#include <SimUtil.h>
#include <gmi_sim.h>
#endif
#include <apfMDS.h>
#include <gmi_null.h>
#include <PCU.h>
#include <spr.h>
#include <apfConvert.h>
#include <gmi_mesh.h>
#include <crv.h>
#ifndef MFEM_USE_PUMI
#error This example requires that MFEM is built with MFEM_USE_PUMI=YES
#endif
using namespace std;
using namespace mfem;
int main(int argc, char *argv[])
{
// 1. Initialize MPI and HYPRE.
Mpi::Init(argc, argv);
int num_procs = Mpi::WorldSize();
int myid = Mpi::WorldRank();
Hypre::Init();
// 2. Parse command-line options.
const char *mesh_file = "../../data/pumi/parallel/Kova/Kova100k_8.smb";
#ifdef MFEM_USE_SIMMETRIX
const char *model_file = "../../data/pumi/geom/Kova.x_t";
const char *smd_file = NULL;
#else
const char *model_file = "../../data/pumi/geom/Kova.dmg";
#endif
int order = 1;
bool static_cond = false;
bool visualization = 1;
int geom_order = 1;
double adapt_ratio = 0.05;
OptionsParser args(argc, argv);
args.AddOption(&mesh_file, "-m", "--mesh",
"Mesh file to use.");
args.AddOption(&order, "-o", "--order",
"Finite element order (polynomial degree) or -1 for"
" isoparametric space.");
args.AddOption(&static_cond, "-sc", "--static-condensation", "-no-sc",
"--no-static-condensation", "Enable static condensation.");
args.AddOption(&visualization, "-vis", "--visualization", "-no-vis",
"--no-visualization",
"Enable or disable GLVis visualization.");
args.AddOption(&model_file, "-p", "--model",
"parasolid or .dmg model to use.");
#ifdef MFEM_USE_SIMMETRIX
args.AddOption(&smd_file, "-sm", "--smd_model",
"smd model file to use.");
#endif
args.AddOption(&geom_order, "-go", "--geometry_order",
"Geometric order of the model");
args.AddOption(&adapt_ratio, "-ar", "--adapt_ratio",
"adaptation factor used in MeshAdapt");
args.Parse();
if (!args.Good())
{
if (myid == 0)
{
args.PrintUsage(cout);
}
return 1;
}
if (myid == 0)
{
args.PrintOptions(cout);
}
// 3. Read the SCOREC Mesh.
PCU_Comm_Init();
#ifdef MFEM_USE_SIMMETRIX
Sim_readLicenseFile(0);
gmi_sim_start();
gmi_register_sim();
#endif
gmi_register_mesh();
apf::Mesh2* pumi_mesh;
#ifdef MFEM_USE_SIMMETRIX
if (smd_file)
{
gmi_model *mixed_model = gmi_sim_load(model_file, smd_file);
pumi_mesh = apf::loadMdsMesh(mixed_model, mesh_file);
}
else
#endif
{
pumi_mesh = apf::loadMdsMesh(model_file, mesh_file);
}
// 4. Increase the geometry order and refine the mesh if necessary. Parallel
// uniform refinement is performed if the total number of elements is less
// than 100,000.
int dim = pumi_mesh->getDimension();
int nEle = pumi_mesh->count(dim);
int ref_levels = (int)floor(log(100000./nEle)/log(2.)/dim);
if (geom_order > 1)
{
crv::BezierCurver bc(pumi_mesh, geom_order, 2);
bc.run();
}
// Perform Uniform refinement
if (myid == 1)
{
std::cout << " ref level : " << ref_levels << std::endl;
}
if (ref_levels > 1)
{
auto uniInput = ma::configureUniformRefine(pumi_mesh, ref_levels);
if ( geom_order > 1)
{
crv::adapt(uniInput);
}
else
{
ma::adapt(uniInput);
}
}
pumi_mesh->verify();
// 5. Create the parallel MFEM mesh object from the parallel PUMI mesh. We
// can handle triangular and tetrahedral meshes. Note that the mesh
// resolution is performed on the PUMI mesh.
ParMesh *pmesh = new ParPumiMesh(MPI_COMM_WORLD, pumi_mesh);
// 6. Define a parallel finite element space on the parallel mesh. Here we
// use continuous Lagrange finite elements of the specified order. If
// order < 1, we instead use an isoparametric/isogeometric space.
FiniteElementCollection *fec;
if (order > 0)
{
fec = new H1_FECollection(order, dim);
}
else if (pmesh->GetNodes())
{
fec = pmesh->GetNodes()->OwnFEC();
if (myid == 1)
{
cout << "Using isoparametric FEs: " << fec->Name() << endl;
}
}
else
{
fec = new H1_FECollection(order = 1, dim);
}
ParFiniteElementSpace *fespace = new ParFiniteElementSpace(pmesh, fec);
HYPRE_BigInt size = fespace->GlobalTrueVSize();
if (myid == 1)
{
cout << "Number of finite element unknowns: " << size << endl;
}
// 7. Set up the parallel linear form b(.) which corresponds to the
// right-hand side of the FEM linear system, which in this case is
// (1,phi_i) where phi_i are the basis functions in fespace.
ParLinearForm *b = new ParLinearForm(fespace);
ConstantCoefficient one(1.0);
b->AddDomainIntegrator(new DomainLFIntegrator(one));
// 8. Define the solution vector x as a parallel finite element grid function
// corresponding to fespace. Initialize x with initial guess of zero,
// which satisfies the boundary conditions.
ParGridFunction x(fespace);
x = 0.0;
// 9. Connect to GLVis.
char vishost[] = "localhost";
int visport = 19916;
socketstream sout;
if (visualization)
{
sout.open(vishost, visport);
if (!sout)
{
if (myid == 0)
{
cout << "Unable to connect to GLVis server at "
<< vishost << ':' << visport << endl;
cout << "GLVis visualization disabled.\n";
}
visualization = false;
}
sout.precision(8);
}
// 10. Set up the parallel bilinear form a(.,.) on the finite element space
// corresponding to the Laplacian operator -Delta, by adding the
// Diffusion domain integrator.
ParBilinearForm *a = new ParBilinearForm(fespace);
a->AddDomainIntegrator(new DiffusionIntegrator(one));
// 11. Assemble the parallel bilinear form and the corresponding linear
// system, applying any necessary transformations such as: parallel
// assembly, eliminating boundary conditions, applying conforming
// constraints for non-conforming AMR, static condensation, etc.
if (static_cond) { a->EnableStaticCondensation(); }
// 12. The main AMR loop. In each iteration we solve the problem on the
// current mesh, visualize the solution, and adapt the mesh.
apf::Field* Tmag_field = 0;
apf::Field* temp_field = 0;
apf::Field* ipfield = 0;
apf::Field* sizefield = 0;
int max_iter = 3;
for (int Itr = 0; Itr < max_iter; Itr++)
{
HYPRE_BigInt global_dofs = fespace->GlobalTrueVSize();
if (myid == 1)
{
cout << "\nAMR iteration " << Itr << endl;
cout << "Number of unknowns: " << global_dofs << endl;
}
// Assemble.
a->Assemble();
b->Assemble();
// Essential boundary condition.
Array<int> ess_tdof_list;
if (pmesh->bdr_attributes.Size())
{
Array<int> ess_bdr(pmesh->bdr_attributes.Max());
ess_bdr = 1;
fespace->GetEssentialTrueDofs(ess_bdr, ess_tdof_list);
}
// Form linear system.
HypreParMatrix A;
Vector B, X;
const int copy_interior = 1;
a->FormLinearSystem(ess_tdof_list, x, *b, A, X, B, copy_interior);
// 13. Define and apply a parallel PCG solver for AX=B with the BoomerAMG
// preconditioner from hypre.
HypreBoomerAMG amg;
amg.SetPrintLevel(0);
CGSolver pcg(A.GetComm());
pcg.SetPreconditioner(amg);
pcg.SetOperator(A);
pcg.SetRelTol(1e-6);
pcg.SetMaxIter(200);
pcg.SetPrintLevel(3); // print the first and the last iterations only
pcg.Mult(B, X);
// 14. Recover the parallel grid function corresponding to X. This is the
// local finite element solution on each processor.
a->RecoverFEMSolution(X, *b, x);
// 15. Save in parallel the displaced mesh and the inverted solution (which
// gives the backward displacements to the original grid). This output
// can be viewed later using GLVis: "glvis -np <np> -m mesh -g sol".
{
ostringstream mesh_name, sol_name;
mesh_name << "mesh." << setfill('0') << setw(6) << myid;
sol_name << "sol." << setfill('0') << setw(6) << myid;
ofstream mesh_ofs(mesh_name.str().c_str());
mesh_ofs.precision(8);
pmesh->Print(mesh_ofs);
ofstream sol_ofs(sol_name.str().c_str());
sol_ofs.precision(8);
x.Save(sol_ofs);
}
// 16. Send the above data by socket to a GLVis server. Use the "n" and "b"
// keys in GLVis to visualize the displacements.
if (visualization)
{
sout << "parallel " << num_procs << " " << myid << "\n";
sout << "solution\n" << *pmesh << x << flush;
}
// 17. Field transfer. Scalar solution field and magnitude field for error
// estimation are created the PUMI mesh.
if (order > geom_order)
{
Tmag_field = apf::createField(pumi_mesh, "field_mag",
apf::SCALAR, apf::getLagrange(order));
temp_field = apf::createField(pumi_mesh, "T_field",
apf::SCALAR, apf::getLagrange(order));
}
else
{
Tmag_field = apf::createFieldOn(pumi_mesh, "field_mag",apf::SCALAR);
temp_field = apf::createFieldOn(pumi_mesh, "T_field", apf::SCALAR);
}
ParPumiMesh* pPPmesh = dynamic_cast<ParPumiMesh*>(pmesh);
pPPmesh->FieldMFEMtoPUMI(pumi_mesh, &x, temp_field, Tmag_field);
ipfield= spr::getGradIPField(Tmag_field, "MFEM_gradip", 2);
sizefield = spr::getSPRSizeField(ipfield, adapt_ratio);
apf::destroyField(Tmag_field);
apf::destroyField(ipfield);
// 18. Perform MesAdapt.
auto erinput = ma::configure(pumi_mesh, sizefield);
if ( geom_order > 1)
{
crv::adapt(erinput);
}
else
{
ma::adapt(erinput);
}
ParMesh* Adapmesh = new ParPumiMesh(MPI_COMM_WORLD, pumi_mesh);
pPPmesh->UpdateMesh(Adapmesh);
delete Adapmesh;
// 19. Update the FiniteElementSpace, GridFunction, and bilinear form.
fespace->Update();
x.Update();
x = 0.0;
pPPmesh->FieldPUMItoMFEM(pumi_mesh, temp_field, &x);
a->Update();
b->Update();
// Destroy fields.
apf::destroyField(temp_field);
apf::destroyField(sizefield);
}
// 20. Free the used memory.
delete a;
delete b;
delete fespace;
if (order > 0) { delete fec; }
delete pmesh;
pumi_mesh->destroyNative();
apf::destroyMesh(pumi_mesh);
PCU_Comm_Free();
#ifdef MFEM_USE_SIMMETRIX
gmi_sim_stop();
Sim_unregisterAllKeys();
#endif
return 0;
}