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mfem/tests/unit/linalg/test_matrix_square.cpp
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camierjs 5c0b2a6b62 Add LDFLAGS for all runs
Fix float-conversion warnings
2025-06-17 15:43:41 -07:00

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// Copyright (c) 2010-2025, Lawrence Livermore National Security, LLC. Produced
// at the Lawrence Livermore National Laboratory. All Rights reserved. See files
// LICENSE and NOTICE for details. LLNL-CODE-806117.
//
// This file is part of the MFEM library. For more information and source code
// availability visit https://mfem.org.
//
// MFEM is free software; you can redistribute it and/or modify it under the
// terms of the BSD-3 license. We welcome feedback and contributions, see file
// CONTRIBUTING.md for details.
#include "unit_tests.hpp"
#include "mfem.hpp"
namespace mfem
{
constexpr real_t EPS = 1.e-12;
TEST_CASE("FormLinearSystem", "[FormLinearSystem]")
{
for (int dim = 2; dim <=3; ++dim)
{
for (int ne = 1; ne <= 4; ++ne)
{
const int n_elements = static_cast<int>(std::pow(ne, dim));
CAPTURE(dim, n_elements);
for (int order = 1; order <= 3; ++order)
{
Mesh mesh;
if (dim == 2)
{
mesh = Mesh::MakeCartesian2D(
ne, ne, Element::QUADRILATERAL, 1, 1.0, 1.0);
}
else
{
mesh = Mesh::MakeCartesian3D(
ne, ne, ne, Element::HEXAHEDRON, 1.0, 1.0, 1.0);
}
FiniteElementCollection *fec = new H1_FECollection(order, dim);
FiniteElementSpace fes(&mesh, fec);
Array<int> ess_tdof_list;
Array<int> ess_bdr(mesh.bdr_attributes.Max());
ess_bdr = 1;
fes.GetEssentialTrueDofs(ess_bdr, ess_tdof_list);
ConstantCoefficient one(1.0);
GridFunction x0(&fes), x1(&fes), b(&fes);
Vector B[2], X[2];
OperatorPtr A_pa, A_fa;
BilinearForm pa(&fes), fa(&fes);
x0 = 0.0;
b = 1.0;
pa.SetAssemblyLevel(AssemblyLevel::PARTIAL);
pa.AddDomainIntegrator(new DiffusionIntegrator(one));
pa.Assemble();
pa.FormLinearSystem(ess_tdof_list, x0, b, A_pa, X[0], B[0]);
OperatorJacobiSmoother M_pa(pa, ess_tdof_list);
PCG(*A_pa, M_pa, B[0], X[0], 0, 1000, EPS*EPS, 0.0);
pa.RecoverFEMSolution(X[0], b, x0);
x1 = 0.0;
b = 1.0;
fa.AddDomainIntegrator(new DiffusionIntegrator(one));
fa.Assemble();
fa.FormLinearSystem(ess_tdof_list, x1, b, A_fa, X[1], B[1]);
DSmoother M_fa((SparseMatrix&)(*A_fa));
PCG(*A_fa, M_fa, B[1], X[1], 0, 1000, EPS*EPS, 0.0);
fa.RecoverFEMSolution(X[1], b, x1);
x0 -= x1;
real_t error = x0.Norml2();
CAPTURE(error, order);
REQUIRE(x0.Norml2() == MFEM_Approx(0.0, 1e2*EPS));
delete fec;
}
}
}
}
#ifdef MFEM_USE_MPI
TEST_CASE("ParallelFormLinearSystem", "[Parallel], [ParallelFormLinearSystem]")
{
for (int dim = 2; dim <= 3; ++dim)
{
for (int ne = 4; ne <= 5; ++ne)
{
const int n_elements = static_cast<int>(std::pow(ne, dim));
CAPTURE(dim, n_elements);
for (int order = 1; order <= 3; ++order)
{
Mesh mesh;
if (dim == 2)
{
mesh = Mesh::MakeCartesian2D(
ne, ne, Element::QUADRILATERAL, 1, 1.0, 1.0);
}
else
{
mesh = Mesh::MakeCartesian3D(
ne, ne, ne, Element::HEXAHEDRON, 1.0, 1.0, 1.0);
}
ParMesh *pmesh = new ParMesh(MPI_COMM_WORLD, mesh);
mesh.Clear();
FiniteElementCollection *fec = new H1_FECollection(order, dim);
ParFiniteElementSpace fes(pmesh, fec);
Array<int> ess_tdof_list;
Array<int> ess_bdr(pmesh->bdr_attributes.Max());
ess_bdr = 1;
fes.GetEssentialTrueDofs(ess_bdr, ess_tdof_list);
ConstantCoefficient one(1.0);
ParGridFunction x0(&fes), x1(&fes), b(&fes);
Vector B[2], X[2];
OperatorPtr A_pa, A_fa;
ParBilinearForm pa(&fes), fa(&fes);
x0 = 0.0;
b = 1.0;
pa.SetAssemblyLevel(AssemblyLevel::PARTIAL);
pa.AddDomainIntegrator(new DiffusionIntegrator(one));
pa.Assemble();
pa.FormLinearSystem(ess_tdof_list, x0, b, A_pa, X[0], B[0]);
Solver *M_pa = new OperatorJacobiSmoother(pa, ess_tdof_list);
CGSolver cg_pa(MPI_COMM_WORLD);
cg_pa.SetRelTol(EPS);
cg_pa.SetMaxIter(1000);
cg_pa.SetPrintLevel(0);
cg_pa.SetPreconditioner(*M_pa);
cg_pa.SetOperator(*A_pa);
cg_pa.Mult(B[0], X[0]);
delete M_pa;
pa.RecoverFEMSolution(X[0], b, x0);
x1 = 0.0;
b = 1.0;
fa.AddDomainIntegrator(new DiffusionIntegrator(one));
fa.Assemble();
fa.FormLinearSystem(ess_tdof_list, x1, b, A_fa, X[1], B[1]);
HypreSmoother M_fa;
M_fa.SetType(HypreSmoother::Jacobi);
CGSolver cg_fa(MPI_COMM_WORLD);
cg_fa.SetRelTol(EPS);
cg_fa.SetMaxIter(1000);
cg_fa.SetPrintLevel(0);
cg_fa.SetPreconditioner(M_fa);
cg_fa.SetOperator(*A_fa);
cg_fa.Mult(B[1], X[1]);
fa.RecoverFEMSolution(X[1], b, x1);
x0 -= x1;
real_t error = x0.Norml2();
CAPTURE(order, error);
REQUIRE(x0.Norml2() == MFEM_Approx(0.0, 2e2*EPS));
delete pmesh;
delete fec;
}
}
}
}
TEST_CASE("HypreParMatrixBlocksSquare",
"[Parallel], [BlockMatrix]")
{
SECTION("HypreParMatrixFromBlocks")
{
int rank;
MPI_Comm_rank(MPI_COMM_WORLD, &rank);
Mesh mesh = Mesh::MakeCartesian2D(
10, 10, Element::QUADRILATERAL, 0, 1.0, 1.0);
int dim = mesh.Dimension();
int order = 2;
int nattr = mesh.bdr_attributes.Max();
Array<int> ess_trial_tdof_list, ess_test_tdof_list;
Array<int> ess_bdr(nattr);
ess_bdr = 0;
ess_bdr[0] = 1;
ParMesh pmesh(MPI_COMM_WORLD, mesh);
FiniteElementCollection *hdiv_coll(new RT_FECollection(order, dim));
FiniteElementCollection *l2_coll(new L2_FECollection(order, dim));
ParFiniteElementSpace R_space(&pmesh, hdiv_coll);
ParFiniteElementSpace W_space(&pmesh, l2_coll);
ParBilinearForm RmVarf(&R_space);
ParBilinearForm WmVarf(&W_space);
ParMixedBilinearForm bVarf(&R_space, &W_space);
HypreParMatrix *MR, *MW, *B;
RmVarf.AddDomainIntegrator(new VectorFEMassIntegrator());
RmVarf.Assemble();
RmVarf.Finalize();
MR = RmVarf.ParallelAssemble();
WmVarf.AddDomainIntegrator(new MassIntegrator());
WmVarf.Assemble();
WmVarf.Finalize();
MW = WmVarf.ParallelAssemble();
bVarf.AddDomainIntegrator(new VectorFEDivergenceIntegrator);
bVarf.Assemble();
bVarf.Finalize();
B = bVarf.ParallelAssemble();
(*B) *= -1;
HypreParMatrix *BT = B->Transpose();
Array<int> blockRow_trueOffsets(3); // number of variables + 1
blockRow_trueOffsets[0] = 0;
blockRow_trueOffsets[1] = R_space.TrueVSize();
blockRow_trueOffsets[2] = W_space.TrueVSize();
blockRow_trueOffsets.PartialSum();
BlockOperator blockOper(blockRow_trueOffsets, blockRow_trueOffsets);
blockOper.SetBlock(0, 0, MR);
blockOper.SetBlock(0, 1, BT);
blockOper.SetBlock(1, 0, B);
blockOper.SetBlock(1, 1, MW, 3.14);
Array2D<const HypreParMatrix*> hBlocks(2,2);
hBlocks = NULL;
hBlocks(0, 0) = MR;
hBlocks(0, 1) = BT;
hBlocks(1, 0) = B;
hBlocks(1, 1) = MW;
Array2D<real_t> blockCoeff(2,2);
blockCoeff = 1.0;
blockCoeff(1, 1) = 3.14;
HypreParMatrix *H = HypreParMatrixFromBlocks(hBlocks, &blockCoeff);
Vector yB(blockRow_trueOffsets[2]);
Vector yH(blockRow_trueOffsets[2]);
Vector yBR(yB, 0, R_space.TrueVSize());
Vector yBW(yB, R_space.TrueVSize(), W_space.TrueVSize());
yB = 0.0;
yH = 0.0;
MR->GetDiag(yBR);
yBR.SyncAliasMemory(yB);
MW->GetDiag(yBW);
yBW *= 3.14;
yBW.SyncAliasMemory(yB);
H->GetDiag(yH);
yH -= yB;
real_t error = yH.Norml2();
mfem::out << " order: " << order
<< ", block matrix error norm on rank " << rank << ": " << error << std::endl;
REQUIRE(error < EPS);
delete H;
delete BT;
delete B;
delete MW;
delete MR;
delete l2_coll;
delete hdiv_coll;
}
}
#endif // MFEM_USE_MPI
} // namespace mfem