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mfem/fem/tmop_tools.cpp
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// Copyright (c) 2010-2020, 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 "tmop_tools.hpp"
#include "nonlinearform.hpp"
#include "pnonlinearform.hpp"
#include "../general/osockstream.hpp"
namespace mfem
{
using namespace mfem;
void AdvectorCG::SetInitialField(const Vector &init_nodes,
const Vector &init_field)
{
nodes0 = init_nodes;
field0 = init_field;
}
void AdvectorCG::ComputeAtNewPosition(const Vector &new_nodes,
Vector &new_field)
{
// TODO: Implement for AMR meshes.
const int pnt_cnt = new_field.Size()/ncomp;
new_field = field0;
for (int i = 0; i < ncomp; i++)
{
Vector new_field_temp(new_field.GetData()+i*pnt_cnt, pnt_cnt);
ComputeAtNewPositionScalar(new_nodes, new_field_temp);
}
field0 = new_field;
nodes0 = new_nodes;
}
void AdvectorCG::ComputeAtNewPositionScalar(const Vector &new_nodes,
Vector &new_field)
{
Mesh *m = mesh;
#ifdef MFEM_USE_MPI
if (pmesh) { m = pmesh; }
#endif
MFEM_VERIFY(m != NULL, "No mesh has been given to the AdaptivityEvaluator.");
// This will be used to move the positions.
GridFunction *mesh_nodes = m->GetNodes();
*mesh_nodes = nodes0;
double minv = new_field.Min(), maxv = new_field.Max();
// Velocity of the positions.
GridFunction u(mesh_nodes->FESpace());
subtract(new_nodes, nodes0, u);
// Define a scalar FE space for the solution, and the advection operator.
TimeDependentOperator *oper = NULL;
FiniteElementSpace *fess = NULL;
#ifdef MFEM_USE_MPI
ParFiniteElementSpace *pfess = NULL;
#endif
if (fes)
{
fess = new FiniteElementSpace(fes->GetMesh(), fes->FEColl(), 1);
oper = new SerialAdvectorCGOper(nodes0, u, *fess);
}
#ifdef MFEM_USE_MPI
else if (pfes)
{
pfess = new ParFiniteElementSpace(pfes->GetParMesh(), pfes->FEColl(), 1);
oper = new ParAdvectorCGOper(nodes0, u, *pfess);
}
#endif
MFEM_VERIFY(oper != NULL,
"No FE space has been given to the AdaptivityEvaluator.");
ode_solver.Init(*oper);
// Compute some time step [mesh_size / speed].
double h_min = std::numeric_limits<double>::infinity();
for (int i = 0; i < m->GetNE(); i++)
{
h_min = std::min(h_min, m->GetElementSize(i));
}
double v_max = 0.0;
const int s = new_field.Size();
for (int i = 0; i < s; i++)
{
double vel = 0.;
for (int j = 0; j < dim; j++)
{
vel += u(i+j*s)*u(i+j*s);
}
v_max = std::max(v_max, vel);
}
#ifdef MFEM_USE_MPI
if (pfes)
{
double v_loc = v_max, h_loc = h_min;
MPI_Allreduce(&v_loc, &v_max, 1, MPI_DOUBLE, MPI_MAX, pfes->GetComm());
MPI_Allreduce(&h_loc, &h_min, 1, MPI_DOUBLE, MPI_MIN, pfes->GetComm());
}
#endif
if (v_max == 0.0) // No need to change the field.
{
delete oper;
delete fess;
#ifdef MFEM_USE_MPI
delete pfess;
#endif
return;
}
v_max = std::sqrt(v_max);
double dt = dt_scale * h_min / v_max;
double t = 0.0;
bool last_step = false;
for (int ti = 1; !last_step; ti++)
{
if (t + dt >= 1.0)
{
dt = 1.0 - t;
last_step = true;
}
ode_solver.Step(new_field, t, dt);
}
double glob_minv = minv,
glob_maxv = maxv;
#ifdef MFEM_USE_MPI
if (pfes)
{
MPI_Allreduce(&minv, &glob_minv, 1, MPI_DOUBLE, MPI_MIN, pfes->GetComm());
MPI_Allreduce(&maxv, &glob_maxv, 1, MPI_DOUBLE, MPI_MAX, pfes->GetComm());
}
#endif
// Trim the overshoots and undershoots.
for (int i = 0; i < s; i++)
{
if (new_field(i) < glob_minv) { new_field(i) = glob_minv; }
if (new_field(i) > glob_maxv) { new_field(i) = glob_maxv; }
}
delete oper;
delete fess;
#ifdef MFEM_USE_MPI
delete pfess;
#endif
}
SerialAdvectorCGOper::SerialAdvectorCGOper(const Vector &x_start,
GridFunction &vel,
FiniteElementSpace &fes)
: TimeDependentOperator(fes.GetVSize()),
x0(x_start), x_now(*fes.GetMesh()->GetNodes()),
u(vel), u_coeff(&u), M(&fes), K(&fes)
{
ConvectionIntegrator *Kinteg = new ConvectionIntegrator(u_coeff);
K.AddDomainIntegrator(Kinteg);
K.Assemble(0);
K.Finalize(0);
MassIntegrator *Minteg = new MassIntegrator;
M.AddDomainIntegrator(Minteg);
M.Assemble();
M.Finalize();
}
void SerialAdvectorCGOper::Mult(const Vector &ind, Vector &di_dt) const
{
// Move the mesh.
const double t = GetTime();
add(x0, t, u, x_now);
// Assemble on the new mesh.
K.BilinearForm::operator=(0.0);
K.Assemble();
Vector rhs(K.Size());
K.Mult(ind, rhs);
M.BilinearForm::operator=(0.0);
M.Assemble();
di_dt = 0.0;
CGSolver lin_solver;
DSmoother prec;
lin_solver.SetPreconditioner(prec);
lin_solver.SetOperator(M.SpMat());
lin_solver.SetRelTol(1e-12); lin_solver.SetAbsTol(0.0);
lin_solver.SetMaxIter(100);
lin_solver.SetPrintLevel(0);
lin_solver.Mult(rhs, di_dt);
}
#ifdef MFEM_USE_MPI
ParAdvectorCGOper::ParAdvectorCGOper(const Vector &x_start,
GridFunction &vel,
ParFiniteElementSpace &pfes)
: TimeDependentOperator(pfes.GetVSize()),
x0(x_start), x_now(*pfes.GetMesh()->GetNodes()),
u(vel), u_coeff(&u), M(&pfes), K(&pfes)
{
ConvectionIntegrator *Kinteg = new ConvectionIntegrator(u_coeff);
K.AddDomainIntegrator(Kinteg);
K.Assemble(0);
K.Finalize(0);
MassIntegrator *Minteg = new MassIntegrator;
M.AddDomainIntegrator(Minteg);
M.Assemble();
M.Finalize();
}
void ParAdvectorCGOper::Mult(const Vector &ind, Vector &di_dt) const
{
// Move the mesh.
const double t = GetTime();
add(x0, t, u, x_now);
// Assemble on the new mesh.
K.BilinearForm::operator=(0.0);
K.Assemble();
ParGridFunction rhs(K.ParFESpace());
K.Mult(ind, rhs);
M.BilinearForm::operator=(0.0);
M.Assemble();
HypreParVector *RHS = rhs.ParallelAssemble();
HypreParVector X(K.ParFESpace());
X = 0.0;
HypreParMatrix *Mh = M.ParallelAssemble();
CGSolver lin_solver(M.ParFESpace()->GetParMesh()->GetComm());
HypreSmoother prec;
prec.SetType(HypreSmoother::Jacobi, 1);
lin_solver.SetPreconditioner(prec);
lin_solver.SetOperator(*Mh);
lin_solver.SetRelTol(1e-8);
lin_solver.SetAbsTol(0.0);
lin_solver.SetMaxIter(100);
lin_solver.SetPrintLevel(0);
lin_solver.Mult(*RHS, X);
K.ParFESpace()->GetProlongationMatrix()->Mult(X, di_dt);
delete Mh;
delete RHS;
}
#endif
#ifdef MFEM_USE_GSLIB
void InterpolatorFP::SetInitialField(const Vector &init_nodes,
const Vector &init_field)
{
nodes0 = init_nodes;
Mesh *m = mesh;
#ifdef MFEM_USE_MPI
if (pmesh) { m = pmesh; }
#endif
m->SetNodes(nodes0);
const double rel_bbox_el = 0.1;
const double newton_tol = 1.0e-12;
const int npts_at_once = 256;
if (finder)
{
finder->FreeData();
delete finder;
}
FiniteElementSpace *f = fes;
#ifdef MFEM_USE_MPI
if (pfes)
{
f = pfes;
finder = new FindPointsGSLIB(pfes->GetComm());
}
else { finder = new FindPointsGSLIB(); }
#else
finder = new FindPointsGSLIB();
#endif
finder->Setup(*m, rel_bbox_el, newton_tol, npts_at_once);
field0_gf.SetSpace(f);
field0_gf = init_field;
dim = f->GetFE(0)->GetDim();
const int pts_cnt = init_nodes.Size() / dim;
el_id_out.SetSize(pts_cnt);
code_out.SetSize(pts_cnt);
task_id_out.SetSize(pts_cnt);
pos_r_out.SetSize(pts_cnt*dim);
dist_p_out.SetSize(pts_cnt);
}
void InterpolatorFP::ComputeAtNewPosition(const Vector &new_nodes,
Vector &new_field)
{
const int pts_cnt = new_nodes.Size() / dim;
// The sizes may change between calls due to AMR.
if (el_id_out.Size() != pts_cnt)
{
el_id_out.SetSize(pts_cnt);
code_out.SetSize(pts_cnt);
task_id_out.SetSize(pts_cnt);
pos_r_out.SetSize(pts_cnt*dim);
dist_p_out(pts_cnt);
}
// Interpolate FE function values on the found points.
finder->FindPoints(new_nodes, code_out, task_id_out,
el_id_out, pos_r_out, dist_p_out);
finder->Interpolate(code_out, task_id_out, el_id_out,
pos_r_out, field0_gf, new_field);
}
#endif
double TMOPNewtonSolver::ComputeScalingFactor(const Vector &x,
const Vector &b) const
{
const FiniteElementSpace *fes = NULL;
double energy_in = 0.0;
#ifdef MFEM_USE_MPI
const ParNonlinearForm *p_nlf = dynamic_cast<const ParNonlinearForm *>(oper);
MFEM_VERIFY(!(parallel && p_nlf == NULL), "Invalid Operator subclass.");
if (parallel)
{
fes = p_nlf->FESpace();
energy_in = p_nlf->GetEnergy(x);
}
#endif
const bool serial = !parallel;
const NonlinearForm *nlf = dynamic_cast<const NonlinearForm *>(oper);
MFEM_VERIFY(!(serial && nlf == NULL), "Invalid Operator subclass.");
if (serial)
{
fes = nlf->FESpace();
energy_in = nlf->GetEnergy(x);
}
const bool have_b = (b.Size() == Height());
const int NE = fes->GetMesh()->GetNE(), dim = fes->GetFE(0)->GetDim(),
dof = fes->GetFE(0)->GetDof(), nsp = ir.GetNPoints();
Array<int> xdofs(dof * dim);
DenseMatrix Jpr(dim), dshape(dof, dim), pos(dof, dim);
Vector posV(pos.Data(), dof * dim);
Vector x_out(x.Size()), x_out_loc(fes->GetVSize());
bool x_out_ok = false;
double scale = 1.0, energy_out = 0.0;
double norm0 = Norm(r);
// Decreases the scaling of the update until the new mesh is valid.
for (int i = 0; i < 12; i++)
{
add(x, -scale, c, x_out);
if (serial)
{
const SparseMatrix *cP = fes->GetConformingProlongation();
if (!cP) { x_out_loc = x_out; }
else { cP->Mult(x_out, x_out_loc); }
}
#ifdef MFEM_USE_MPI
else
{
fes->GetProlongationMatrix()->Mult(x_out, x_out_loc);
}
#endif
int jac_ok = 1;
for (int i = 0; i < NE; i++)
{
fes->GetElementVDofs(i, xdofs);
x_out_loc.GetSubVector(xdofs, posV);
for (int j = 0; j < nsp; j++)
{
fes->GetFE(i)->CalcDShape(ir.IntPoint(j), dshape);
MultAtB(pos, dshape, Jpr);
if (Jpr.Det() <= 0.0) { jac_ok = 0; goto break2; }
}
}
break2:
int jac_ok_all = jac_ok;
#ifdef MFEM_USE_MPI
if (parallel)
{
MPI_Allreduce(&jac_ok, &jac_ok_all, 1, MPI_INT, MPI_LAND,
p_nlf->ParFESpace()->GetComm());
}
#endif
if (jac_ok_all == 0)
{
if (print_level >= 0)
{ mfem::out << "Scale = " << scale << " Neg det(J) found.\n"; }
scale *= 0.5; continue;
}
ProcessNewState(x_out);
if (serial)
{
energy_out = nlf->GetGridFunctionEnergy(x_out_loc);
}
#ifdef MFEM_USE_MPI
else
{
energy_out = p_nlf->GetParGridFunctionEnergy(x_out_loc);
}
#endif
if (energy_out > 1.2*energy_in || std::isnan(energy_out) != 0)
{
if (print_level >= 0)
{ mfem::out << "Scale = " << scale << " Increasing energy.\n"; }
scale *= 0.5; continue;
}
oper->Mult(x_out, r);
if (have_b) { r -= b; }
double norm = Norm(r);
if (norm > 1.2*norm0)
{
if (print_level >= 0)
{ mfem::out << "Scale = " << scale << " Norm increased.\n"; }
scale *= 0.5; continue;
}
else { x_out_ok = true; break; }
}
if (print_level >= 0)
{
mfem::out << "Energy decrease: "
<< (energy_in - energy_out) / energy_in * 100.0
<< "% with " << scale << " scaling.\n";
}
if (x_out_ok == false) { scale = 0.0; }
return scale;
}
void TMOPNewtonSolver::ProcessNewState(const Vector &x) const
{
const NonlinearForm *nlf = dynamic_cast<const NonlinearForm *>(oper);
const Array<NonlinearFormIntegrator*> &integs = *nlf->GetDNFI();
// Reset the update flags of all TargetConstructors.
// This is done to avoid repeated updates of shared TargetConstructors.
TMOP_Integrator *ti = NULL;
TMOPComboIntegrator *co = NULL;
DiscreteAdaptTC *dtc = NULL;
for (int i = 0; i < integs.Size(); i++)
{
ti = dynamic_cast<TMOP_Integrator *>(integs[i]);
if (ti)
{
dtc = ti->GetDiscreteAdaptTC();
if (dtc) { dtc->ResetUpdateFlags(); }
}
co = dynamic_cast<TMOPComboIntegrator *>(integs[i]);
if (co)
{
Array<TMOP_Integrator *> ati = co->GetTMOPIntegrators();
for (int j = 0; j < ati.Size(); j++)
{
dtc = ati[j]->GetDiscreteAdaptTC();
if (dtc) { dtc->ResetUpdateFlags(); }
}
}
}
if (parallel)
{
#ifdef MFEM_USE_MPI
const ParNonlinearForm *nlf =
dynamic_cast<const ParNonlinearForm *>(oper);
const ParFiniteElementSpace *pfesc = nlf->ParFESpace();
Vector x_loc(pfesc->GetVSize());
pfesc->GetProlongationMatrix()->Mult(x, x_loc);
for (int i = 0; i < integs.Size(); i++)
{
ti = dynamic_cast<TMOP_Integrator *>(integs[i]);
if (ti)
{
ti->UpdateAfterMeshChange(x_loc);
ti->ComputeFDh(x_loc, *pfesc);
UpdateDiscreteTC(*ti, x_loc);
}
co = dynamic_cast<TMOPComboIntegrator *>(integs[i]);
if (co)
{
Array<TMOP_Integrator *> ati = co->GetTMOPIntegrators();
for (int j = 0; j < ati.Size(); j++)
{
ati[j]->ComputeFDh(x_loc, *pfesc);
UpdateDiscreteTC(*ati[j], x_loc);
}
}
}
#endif
}
else
{
const FiniteElementSpace *fesc = nlf->FESpace();
const Operator *P = nlf->GetProlongation();
Vector x_loc;
if (P)
{
x_loc.SetSize(P->Height());
P->Mult(x,x_loc);
}
else
{
x_loc = x;
}
for (int i = 0; i < integs.Size(); i++)
{
ti = dynamic_cast<TMOP_Integrator *>(integs[i]);
if (ti)
{
ti->UpdateAfterMeshChange(x_loc);
ti->ComputeFDh(x_loc, *fesc);
UpdateDiscreteTC(*ti, x_loc);
}
co = dynamic_cast<TMOPComboIntegrator *>(integs[i]);
if (co)
{
Array<TMOP_Integrator *> ati = co->GetTMOPIntegrators();
for (int j = 0; j < ati.Size(); j++)
{
ati[j]->ComputeFDh(x_loc, *fesc);
UpdateDiscreteTC(*ati[j], x_loc);
}
}
}
}
}
void TMOPNewtonSolver::UpdateDiscreteTC(const TMOP_Integrator &ti,
const Vector &x_new) const
{
const bool update_flag = true;
DiscreteAdaptTC *discrtc = ti.GetDiscreteAdaptTC();
if (discrtc)
{
discrtc->UpdateTargetSpecification(x_new, update_flag);
if (ti.GetFDFlag())
{
double dx = ti.GetFDh();
discrtc->UpdateGradientTargetSpecification(x_new, dx, update_flag);
discrtc->UpdateHessianTargetSpecification(x_new, dx, update_flag);
}
}
}
double TMOPDescentNewtonSolver::ComputeScalingFactor(const Vector &x,
const Vector &b) const
{
const FiniteElementSpace *fes = NULL;
double energy_in = 0.0;
#ifdef MFEM_USE_MPI
const ParNonlinearForm *p_nlf = dynamic_cast<const ParNonlinearForm *>(oper);
MFEM_VERIFY(!(parallel && p_nlf == NULL), "Invalid Operator subclass.");
if (parallel)
{
fes = p_nlf->FESpace();
energy_in = p_nlf->GetEnergy(x);
}
#endif
const bool serial = !parallel;
const NonlinearForm *nlf = dynamic_cast<const NonlinearForm *>(oper);
MFEM_VERIFY(!(serial && nlf == NULL), "Invalid Operator subclass.");
if (serial)
{
fes = nlf->FESpace();
energy_in = nlf->GetEnergy(x);
}
const int NE = fes->GetMesh()->GetNE(), dim = fes->GetFE(0)->GetDim(),
dof = fes->GetFE(0)->GetDof(), nsp = ir.GetNPoints();
Array<int> xdofs(dof * dim);
DenseMatrix Jpr(dim), dshape(dof, dim), pos(dof, dim);
Vector posV(pos.Data(), dof * dim);
Vector x_loc(fes->GetVSize());
double min_detJ = infinity();
for (int i = 0; i < NE; i++)
{
fes->GetElementVDofs(i, xdofs);
// TODO x_loc doesn't have valid values here!
MFEM_ABORT("This function has to be fixed!");
x_loc.GetSubVector(xdofs, posV);
for (int j = 0; j < nsp; j++)
{
fes->GetFE(i)->CalcDShape(ir.IntPoint(j), dshape);
MultAtB(pos, dshape, Jpr);
min_detJ = std::min(min_detJ, Jpr.Det());
}
}
double min_detJ_all = min_detJ;
#ifdef MFEM_USE_MPI
if (parallel)
{
MPI_Allreduce(&min_detJ, &min_detJ_all, 1, MPI_DOUBLE, MPI_MIN,
p_nlf->ParFESpace()->GetComm());
}
#endif
if (print_level >= 0)
{
mfem::out << "Minimum det(J) = " << min_detJ_all << '\n';
}
Vector x_out(x.Size());
bool x_out_ok = false;
double scale = 1.0, energy_out = 0.0;
for (int i = 0; i < 7; i++)
{
add(x, -scale, c, x_out);
if (serial)
{
const SparseMatrix *cP = fes->GetConformingProlongation();
if (!cP) { x_loc = x_out; }
else { cP->Mult(x_out,x_loc); }
energy_out = nlf->GetGridFunctionEnergy(x_loc);
}
#ifdef MFEM_USE_MPI
else
{
fes->GetProlongationMatrix()->Mult(x_out, x_loc);
energy_out = p_nlf->GetParGridFunctionEnergy(x_loc);
}
#endif
if (energy_out > energy_in || std::isnan(energy_out) != 0)
{
scale *= 0.5;
}
else { x_out_ok = true; break; }
}
if (print_level >= 0)
{
mfem::out << "Energy decrease: "
<< (energy_in - energy_out) / energy_in * 100.0
<< "% with " << scale << " scaling.\n";
}
if (x_out_ok == false) { return 0.0; }
return scale;
}
#ifdef MFEM_USE_MPI
// Metric values are visualized by creating an L2 finite element functions and
// computing the metric values at the nodes.
void vis_tmop_metric_p(int order, TMOP_QualityMetric &qm,
const TargetConstructor &tc, ParMesh &pmesh,
char *title, int position)
{
L2_FECollection fec(order, pmesh.Dimension(), BasisType::GaussLobatto);
ParFiniteElementSpace fes(&pmesh, &fec, 1);
ParGridFunction metric(&fes);
InterpolateTMOP_QualityMetric(qm, tc, pmesh, metric);
socketstream sock;
if (pmesh.GetMyRank() == 0)
{
sock.open("localhost", 19916);
sock << "solution\n";
}
pmesh.PrintAsOne(sock);
metric.SaveAsOne(sock);
if (pmesh.GetMyRank() == 0)
{
sock << "window_title '"<< title << "'\n"
<< "window_geometry "
<< position << " " << 0 << " " << 600 << " " << 600 << "\n"
<< "keys jRmclA\n";
}
}
#endif
// Metric values are visualized by creating an L2 finite element functions and
// computing the metric values at the nodes.
void vis_tmop_metric_s(int order, TMOP_QualityMetric &qm,
const TargetConstructor &tc, Mesh &mesh,
char *title, int position)
{
L2_FECollection fec(order, mesh.Dimension(), BasisType::GaussLobatto);
FiniteElementSpace fes(&mesh, &fec, 1);
GridFunction metric(&fes);
InterpolateTMOP_QualityMetric(qm, tc, mesh, metric);
osockstream sock(19916, "localhost");
sock << "solution\n";
mesh.Print(sock);
metric.Save(sock);
sock.send();
sock << "window_title '"<< title << "'\n"
<< "window_geometry "
<< position << " " << 0 << " " << 600 << " " << 600 << "\n"
<< "keys jRmclA\n";
}
}