1 // Copyright (c) 2017-2026, Lawrence Livermore National Security, LLC and other CEED contributors.
2 // All Rights Reserved. See the top-level LICENSE and NOTICE files for details.
4 // SPDX-License-Identifier: BSD-2-Clause
14 // CeedDiffusionOperator uses a CeedOperator object constructed based on an mfem::FiniteElementSpac…
15 // object constructed based on a command line argument. (-ceed).
24 // Sample runs:
27 //     ./bp3 -ceed /cpu/self
28 //     ./bp3 -ceed /gpu/cuda
29 //     ./bp3 -m ../../../mfem/data/fichera.mesh -o 4
30 //     ./bp3 -m ../../../mfem/data/square-disc-nurbs.mesh -o 6
31 //     ./bp3 -m ../../../mfem/data/inline-segment.mesh -o 8
34 /// MFEM diffusion operator based on libCEED
44   static const double x[3] = {-0.32, 0.15, 0.24};  in solution()
51 /// Right-hand side
53   static const double x[3] = {-0.32, 0.15, 0.24};  in rhs()
69 //TESTARGS -ceed {ceed_resource} -t -no-vis --size 2000
71   // 1. Parse command-line options.  in main()
84   args.AddOption(&ceed_spec, "-c", "-ceed", "Ceed specification.");  in main()
85   args.AddOption(&mesh_file, "-m", "--mesh", "Mesh file to use.");  in main()
86   args.AddOption(&order, "-o", "--order", "Finite element order (polynomial degree).");  in main()
87   args.AddOption(&max_nnodes, "-s", "--size", "Maximum size (number of DoFs)");  in main()
88 …args.AddOption(&visualization, "-vis", "--visualization", "-no-vis", "--no-visualization", "Enable…  in main()
89   args.AddOption(&test, "-t", "--test", "-no-test", "--no-test", "Enable or disable test mode.");  in main()
105   int         dim  = mesh->Dimension();  in main()
111 … int ref_levels = (int)floor((log(max_nnodes / mesh->GetNE()) - dim * log(order)) / log(2.) / dim);  in main()
113       mesh->UniformRefinement();  in main()
116   if (mesh->GetNodalFESpace() == NULL) {  in main()
117     mesh->SetCurvature(1, false, -1, mfem::Ordering::byNODES);  in main()
119   if (mesh->NURBSext) {  in main()
120     mesh->SetCurvature(order, false, -1, mfem::Ordering::byNODES);  in main()
123   // 5. Define a finite element space on the mesh.  in main()
129     std::cout << "Number of finite element unknowns: " << fespace->GetTrueVSize() << std::endl;  in main()
135   if (mesh->bdr_attributes.Size()) {  in main()
136     mfem::Array<int> ess_bdr(mesh->bdr_attributes.Max());  in main()
138     fespace->GetEssentialTrueDofs(ess_bdr, ess_tdof_list);  in main()
157   cg.SetRelTol(1e-6);  in main()
173     if (fabs(sol.ComputeL2Error(sol_coeff)) > 2e-3) {  in main()