MFEM  v4.6.0
Finite element discretization library
nurbs_ex1p.cpp
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1 // MFEM Example 1 - Parallel NURBS Version
2 //
3 // Compile with: make nurbs_ex1p
4 //
5 // Sample runs: mpirun -np 4 nurbs_ex1p -m ../../data/square-disc.mesh
6 // mpirun -np 4 nurbs_ex1p -m ../../data/star.mesh
7 // mpirun -np 4 nurbs_ex1p -m ../../data/escher.mesh
8 // mpirun -np 4 nurbs_ex1p -m ../../data/fichera.mesh
9 // mpirun -np 4 nurbs_ex1p -m ../../data/square-disc-p2.vtk -o 2
10 // mpirun -np 4 nurbs_ex1p -m ../../data/square-disc-p3.mesh -o 3
11 // mpirun -np 4 nurbs_ex1p -m ../../data/square-disc-nurbs.mesh -o -1
12 // mpirun -np 4 nurbs_ex1p -m ../../data/disc-nurbs.mesh -o -1
13 // mpirun -np 4 nurbs_ex1p -m ../../data/pipe-nurbs.mesh -o -1
14 // mpirun -np 4 nurbs_ex1p -m ../../data/ball-nurbs.mesh -o 2
15 // mpirun -np 4 nurbs_ex1p -m ../../data/star-surf.mesh
16 // mpirun -np 4 nurbs_ex1p -m ../../data/square-disc-surf.mesh
17 // mpirun -np 4 nurbs_ex1p -m ../../data/inline-segment.mesh
18 // mpirun -np 4 nurbs_ex1p -m ../../data/amr-quad.mesh
19 // mpirun -np 4 nurbs_ex1p -m ../../data/amr-hex.mesh
20 // mpirun -np 4 nurbs_ex1p -m ../../data/mobius-strip.mesh
21 // mpirun -np 4 nurbs_ex1p -m ../../data/mobius-strip.mesh -o -1 -sc
22 // mpirun -np 4 nurbs_ex1p -m ../../data/square-disc-nurbs.mesh -o -1
23 // mpirun -np 4 nurbs_ex1p -m ../../data/disc-nurbs.mesh -o -1
24 // mpirun -np 4 nurbs_ex1p -m ../../data/pipe-nurbs.mesh -o -1
25 // mpirun -np 4 nurbs_ex1p -m ../../data/square-nurbs.mesh -o 2 -no-ibp
26 // mpirun -np 4 nurbs_ex1p -m ../../data/cube-nurbs.mesh -o 2 -no-ibp
27 // mpirun -np 4 nurbs_ex1p -m ../../data/pipe-nurbs-2d.mesh -o 2 -no-ibp
28 // mpirun -np 4 nurbs_ex1p -m ../../../miniapps/nurbs/meshes/square-nurbs.mesh -r 4 -pm "1" -ps "2"
29 //
30 
31 // Description: This example code demonstrates the use of MFEM to define a
32 // simple finite element discretization of the Laplace problem
33 // -Delta u = 1 with homogeneous Dirichlet boundary conditions.
34 // Specifically, we discretize using a FE space of the specified
35 // order, or if order < 1 using an isoparametric/isogeometric
36 // space (i.e. quadratic for quadratic curvilinear mesh, NURBS for
37 // NURBS mesh, etc.)
38 //
39 // The example highlights the use of mesh refinement, finite
40 // element grid functions, as well as linear and bilinear forms
41 // corresponding to the left-hand side and right-hand side of the
42 // discrete linear system. We also cover the explicit elimination
43 // of essential boundary conditions, static condensation, and the
44 // optional connection to the GLVis tool for visualization.
45 
46 #include "mfem.hpp"
47 #include <fstream>
48 #include <iostream>
49 
50 using namespace std;
51 using namespace mfem;
52 /** Class for integrating the bilinear form a(u,v) := (Q Laplace u, v) where Q
53  can be a scalar coefficient. */
54 class Diffusion2Integrator: public BilinearFormIntegrator
55 {
56 private:
57 #ifndef MFEM_THREAD_SAFE
58  Vector shape,laplace;
59 #endif
60  Coefficient *Q;
61 
62 public:
63  /// Construct a diffusion integrator with coefficient Q = 1
64  Diffusion2Integrator() { Q = NULL; }
65 
66  /// Construct a diffusion integrator with a scalar coefficient q
67  Diffusion2Integrator (Coefficient &q) : Q(&q) { }
68 
69  /** Given a particular Finite Element
70  computes the element stiffness matrix elmat. */
71  virtual void AssembleElementMatrix(const FiniteElement &el,
72  ElementTransformation &Trans,
73  DenseMatrix &elmat)
74  {
75  int nd = el.GetDof();
76  int dim = el.GetDim();
77  double w;
78 
79 #ifdef MFEM_THREAD_SAFE
80  Vector shape(nd);
81  Vector laplace(nd);
82 #else
83  shape.SetSize(nd);
84  laplace.SetSize(nd);
85 #endif
86  elmat.SetSize(nd);
87 
88  const IntegrationRule *ir = IntRule;
89  if (ir == NULL)
90  {
91  int order;
92  if (el.Space() == FunctionSpace::Pk)
93  {
94  order = 2*el.GetOrder() - 2;
95  }
96  else
97  {
98  order = 2*el.GetOrder() + dim - 1;
99  }
100 
101  if (el.Space() == FunctionSpace::rQk)
102  {
103  ir = &RefinedIntRules.Get(el.GetGeomType(),order);
104  }
105  else
106  {
107  ir = &IntRules.Get(el.GetGeomType(),order);
108  }
109  }
110 
111  elmat = 0.0;
112  for (int i = 0; i < ir->GetNPoints(); i++)
113  {
114  const IntegrationPoint &ip = ir->IntPoint(i);
115  Trans.SetIntPoint(&ip);
116  w = -ip.weight * Trans.Weight();
117 
118  el.CalcShape(ip, shape);
119  el.CalcPhysLaplacian(Trans, laplace);
120 
121  if (Q)
122  {
123  w *= Q->Eval(Trans, ip);
124  }
125 
126  for (int jj = 0; jj < nd; jj++)
127  {
128  for (int ii = 0; ii < nd; ii++)
129  {
130  elmat(ii, jj) += w*shape(ii)*laplace(jj);
131  }
132  }
133  }
134  }
135 
136 };
137 
138 int main(int argc, char *argv[])
139 {
140  // 1. Initialize MPI and HYPRE.
141  Mpi::Init(argc, argv);
142  int num_procs = Mpi::WorldSize();
143  int myid = Mpi::WorldRank();
144  Hypre::Init();
145 
146  // 2. Parse command-line options.
147  const char *mesh_file = "../../data/star.mesh";
148  int ref_levels = -1;
149  Array<int> order(1);
150  order[0] = 1;
151  bool static_cond = false;
152  bool visualization = 1;
153  bool ibp = 1;
154  bool strongBC = 1;
155  double kappa = -1;
156  Array<int> master(0);
157  Array<int> slave(0);
158 
159  OptionsParser args(argc, argv);
160  args.AddOption(&mesh_file, "-m", "--mesh",
161  "Mesh file to use.");
162  args.AddOption(&ref_levels, "-r", "--refine",
163  "Number of times to refine the mesh uniformly, -1 for auto.");
164  args.AddOption(&master, "-pm", "--master",
165  "Master boundaries for periodic BCs");
166  args.AddOption(&slave, "-ps", "--slave",
167  "Slave boundaries for periodic BCs");
168  args.AddOption(&order, "-o", "--order",
169  "Finite element order (polynomial degree) or -1 for"
170  " isoparametric space.");
171  args.AddOption(&ibp, "-ibp", "--ibp", "-no-ibp",
172  "--no-ibp",
173  "Selects the standard weak form (IBP) or the nonstandard (NO-IBP).");
174  args.AddOption(&strongBC, "-sbc", "--strong-bc", "-wbc",
175  "--weak-bc",
176  "Selects strong or weak enforcement of Dirichlet BCs.");
177  args.AddOption(&kappa, "-k", "--kappa",
178  "Sets the SIPG penalty parameters, should be positive."
179  " Negative values are replaced with (order+1)^2.");
180  args.AddOption(&static_cond, "-sc", "--static-condensation", "-no-sc",
181  "--no-static-condensation", "Enable static condensation.");
182  args.AddOption(&visualization, "-vis", "--visualization", "-no-vis",
183  "--no-visualization",
184  "Enable or disable GLVis visualization.");
185  args.Parse();
186  if (!args.Good())
187  {
188  if (myid == 0)
189  {
190  args.PrintUsage(cout);
191  }
192  return 1;
193  }
194  if (!strongBC & (kappa < 0))
195  {
196  kappa = 4*(order.Max()+1)*(order.Max()+1);
197  }
198  if (myid == 0)
199  {
200  args.PrintOptions(cout);
201  }
202 
203  // 3. Read the (serial) mesh from the given mesh file on all processors. We
204  // can handle triangular, quadrilateral, tetrahedral, hexahedral, surface
205  // and volume meshes with the same code.
206  Mesh *mesh = new Mesh(mesh_file, 1, 1);
207  int dim = mesh->Dimension();
208 
209  // 4. Refine the serial mesh on all processors to increase the resolution. In
210  // this example we do 'ref_levels' of uniform refinement. We choose
211  // 'ref_levels' to be the largest number that gives a final mesh with no
212  // more than 10,000 elements.
213  {
214  if (ref_levels < 0)
215  {
216  ref_levels =
217  (int)floor(log(5000./mesh->GetNE())/log(2.)/dim);
218  }
219 
220  for (int l = 0; l < ref_levels; l++)
221  {
222  mesh->UniformRefinement();
223  }
224  if (myid == 0)
225  {
226  mesh->PrintInfo();
227  }
228  }
229 
230  // 5. Define a parallel mesh by a partitioning of the serial mesh. Refine
231  // this mesh further in parallel to increase the resolution. Once the
232  // parallel mesh is defined, the serial mesh can be deleted.
233  ParMesh *pmesh = new ParMesh(MPI_COMM_WORLD, *mesh);
234  delete mesh;
235  if (!pmesh->NURBSext)
236  {
237  int par_ref_levels = 2;
238  for (int l = 0; l < par_ref_levels; l++)
239  {
240  pmesh->UniformRefinement();
241  }
242  }
243 
244  // 6. Define a parallel finite element space on the parallel mesh. Here we
245  // use continuous Lagrange finite elements of the specified order. If
246  // order < 1, we instead use an isoparametric/isogeometric space.
248  NURBSExtension *NURBSext = NULL;
249  int own_fec = 0;
250 
251  if (order[0] == -1) // Isoparametric
252  {
253  if (pmesh->GetNodes())
254  {
255  fec = pmesh->GetNodes()->OwnFEC();
256  own_fec = 0;
257  cout << "Using isoparametric FEs: " << fec->Name() << endl;
258  }
259  else
260  {
261  cout <<"Mesh does not have FEs --> Assume order 1.\n";
262  fec = new H1_FECollection(1, dim);
263  own_fec = 1;
264  }
265  }
266  else if (pmesh->NURBSext && (order[0] > 0) ) // Subparametric NURBS
267  {
268  fec = new NURBSFECollection(order[0]);
269  own_fec = 1;
270  int nkv = pmesh->NURBSext->GetNKV();
271 
272  if (order.Size() == 1)
273  {
274  int tmp = order[0];
275  order.SetSize(nkv);
276  order = tmp;
277  }
278  if (order.Size() != nkv ) { mfem_error("Wrong number of orders set."); }
279  NURBSext = new NURBSExtension(pmesh->NURBSext, order);
280 
281  // Enforce periodic BC's
282  if (master.Size() > 0)
283  {
284  if (myid == 0)
285  {
286  cout<<"Connecting boundaries"<<endl;
287  cout<<" - master : "; master.Print();
288  cout<<" - slave : "; slave.Print();
289  }
290 
291  NURBSext->ConnectBoundaries(master,slave);
292  }
293  }
294  else
295  {
296  if (order.Size() > 1) { cout <<"Wrong number of orders set, needs one.\n"; }
297  fec = new H1_FECollection(abs(order[0]), dim);
298  own_fec = 1;
299  }
300  ParFiniteElementSpace *fespace = new ParFiniteElementSpace(pmesh,NURBSext,fec);
301  HYPRE_BigInt size = fespace->GlobalTrueVSize();
302  if (myid == 0)
303  {
304  cout << "Number of finite element unknowns: " << size << endl;
305  }
306 
307  if (!ibp)
308  {
309  if (!pmesh->NURBSext)
310  {
311  cout << "No integration by parts requires a NURBS mesh."<< endl;
312  return 2;
313  }
314  if (pmesh->NURBSext->GetNP()>1)
315  {
316  cout << "No integration by parts requires a NURBS mesh, with only 1 patch."<<
317  endl;
318  cout << "A C_1 discretisation is required."<< endl;
319  cout << "Currently only C_0 multipatch coupling implemented."<< endl;
320  return 3;
321  }
322  if (order[0]<2)
323  {
324  cout << "No integration by parts requires at least quadratic NURBS."<< endl;
325  cout << "A C_1 discretisation is required."<< endl;
326  return 4;
327  }
328  }
329 
330  // 7. Determine the list of true (i.e. parallel conforming) essential
331  // boundary dofs. In this example, the boundary conditions are defined
332  // by marking all the boundary attributes from the mesh as essential
333  // (Dirichlet) and converting them to a list of true dofs.
334  Array<int> ess_tdof_list;
335  if (pmesh->bdr_attributes.Size())
336  {
337  Array<int> ess_bdr(pmesh->bdr_attributes.Max());
338  if (strongBC)
339  {
340  ess_bdr = 1;
341  }
342  else
343  {
344  ess_bdr = 0;
345  }
346 
347  // Remove periodic BCs from essential boundary list
348  for (int i = 0; i < master.Size(); i++)
349  {
350  ess_bdr[master[i]-1] = 0;
351  ess_bdr[slave[i]-1] = 0;
352  }
353 
354  fespace->GetEssentialTrueDofs(ess_bdr, ess_tdof_list);
355  }
356 
357  // 8. Set up the parallel linear form b(.) which corresponds to the
358  // right-hand side of the FEM linear system, which in this case is
359  // (1,phi_i) where phi_i are the basis functions in fespace.
360  ConstantCoefficient one(1.0);
361  ConstantCoefficient zero(0.0);
362 
363  ParLinearForm *b = new ParLinearForm(fespace);
364  b->AddDomainIntegrator(new DomainLFIntegrator(one));
365 
366  if (!strongBC)
367  b->AddBdrFaceIntegrator(
368  new DGDirichletLFIntegrator(zero, one, -1.0, kappa));
369  b->Assemble();
370 
371  // 9. Define the solution vector x as a parallel finite element grid function
372  // corresponding to fespace. Initialize x with initial guess of zero,
373  // which satisfies the boundary conditions.
374  ParGridFunction x(fespace);
375  x = 0.0;
376 
377  // 10. Set up the parallel bilinear form a(.,.) on the finite element space
378  // corresponding to the Laplacian operator -Delta, by adding the Diffusion
379  // domain integrator.
380  ParBilinearForm *a = new ParBilinearForm(fespace);
381  if (ibp)
382  {
383  a->AddDomainIntegrator(new DiffusionIntegrator(one));
384  }
385  else
386  {
387  a->AddDomainIntegrator(new Diffusion2Integrator(one));
388  }
389  if (!strongBC)
390  {
391  a->AddBdrFaceIntegrator(new DGDiffusionIntegrator(one, -1.0, kappa));
392  }
393 
394  // 11. Assemble the parallel bilinear form and the corresponding linear
395  // system, applying any necessary transformations such as: parallel
396  // assembly, eliminating boundary conditions, applying conforming
397  // constraints for non-conforming AMR, static condensation, etc.
398  if (static_cond) { a->EnableStaticCondensation(); }
399  a->Assemble();
400 
401  HypreParMatrix A;
402  Vector B, X;
403  a->FormLinearSystem(ess_tdof_list, x, *b, A, X, B);
404 
405  if (myid == 0)
406  {
407  cout << "Size of linear system: " << A.GetGlobalNumRows() << endl;
408  }
409 
410  // 12. Define and apply a parallel PCG solver for AX=B with the BoomerAMG
411  // preconditioner from hypre.
412  HypreSolver *amg = new HypreBoomerAMG(A);
413  HyprePCG *pcg = new HyprePCG(A);
414  pcg->SetTol(1e-12);
415  pcg->SetMaxIter(200);
416  pcg->SetPrintLevel(2);
417  pcg->SetPreconditioner(*amg);
418  pcg->Mult(B, X);
419 
420  // 13. Recover the parallel grid function corresponding to X. This is the
421  // local finite element solution on each processor.
422  a->RecoverFEMSolution(X, *b, x);
423 
424  // 14. Save the refined mesh and the solution in parallel. This output can
425  // be viewed later using GLVis: "glvis -np <np> -m mesh -g sol".
426  {
427  ostringstream mesh_name, sol_name;
428  mesh_name << "mesh." << setfill('0') << setw(6) << myid;
429  sol_name << "sol." << setfill('0') << setw(6) << myid;
430 
431  ofstream mesh_ofs(mesh_name.str().c_str());
432  mesh_ofs.precision(8);
433  pmesh->Print(mesh_ofs);
434 
435  ofstream sol_ofs(sol_name.str().c_str());
436  sol_ofs.precision(8);
437  x.Save(sol_ofs);
438  }
439 
440  // 15. Send the solution by socket to a GLVis server.
441  if (visualization)
442  {
443  char vishost[] = "localhost";
444  int visport = 19916;
445  socketstream sol_sock(vishost, visport);
446  sol_sock << "parallel " << num_procs << " " << myid << "\n";
447  sol_sock.precision(8);
448  sol_sock << "solution\n" << *pmesh << x << flush;
449  }
450 
451  // 16. Save data in the VisIt format
452  VisItDataCollection visit_dc("Example1-Parallel", pmesh);
453  visit_dc.RegisterField("solution", &x);
454  visit_dc.Save();
455 
456  // 17. Free the used memory.
457  delete pcg;
458  delete amg;
459  delete a;
460  delete b;
461  delete fespace;
462  if (own_fec) { delete fec; }
463  delete pmesh;
464 
465  return 0;
466 }
Abstract class for all finite elements.
Definition: fe_base.hpp:233
Arbitrary order non-uniform rational B-splines (NURBS) finite elements.
Definition: fe_coll.hpp:649
void SetTol(double tol)
Definition: hypre.cpp:3990
int main(int argc, char *argv[])
Definition: nurbs_ex1p.cpp:138
Class for domain integration L(v) := (f, v)
Definition: lininteg.hpp:108
virtual void GetEssentialTrueDofs(const Array< int > &bdr_attr_is_ess, Array< int > &ess_tdof_list, int component=-1)
Definition: pfespace.cpp:1031
int visport
int GetNPoints() const
Returns the number of the points in the integration rule.
Definition: intrules.hpp:253
Class for an integration rule - an Array of IntegrationPoint.
Definition: intrules.hpp:96
const IntegrationRule & Get(int GeomType, int Order)
Returns an integration rule for given GeomType and Order.
Definition: intrules.cpp:980
A coefficient that is constant across space and time.
Definition: coefficient.hpp:84
void PrintOptions(std::ostream &out) const
Print the options.
Definition: optparser.cpp:331
virtual void PrintInfo(std::ostream &os=mfem::out)
In serial, this method calls PrintCharacteristics(). In parallel, additional information about the pa...
Definition: mesh.hpp:2088
int Dimension() const
Dimension of the reference space used within the elements.
Definition: mesh.hpp:1020
void SetSize(int s)
Resize the vector to size s.
Definition: vector.hpp:517
int Space() const
Returns the type of FunctionSpace on the element.
Definition: fe_base.hpp:337
void PrintUsage(std::ostream &out) const
Print the usage message.
Definition: optparser.cpp:462
virtual void Mult(const HypreParVector &b, HypreParVector &x) const
Solve Ax=b with hypre&#39;s PCG.
Definition: hypre.cpp:4038
void SetIntPoint(const IntegrationPoint *ip)
Set the integration point ip that weights and Jacobians will be evaluated at.
Definition: eltrans.hpp:93
virtual void CalcPhysLaplacian(ElementTransformation &Trans, Vector &Laplacian) const
Evaluate the Laplacian of all shape functions of a scalar finite element in reference space at the gi...
Definition: fe_base.cpp:203
T Max() const
Find the maximal element in the array, using the comparison operator < for class T.
Definition: array.cpp:68
Data type dense matrix using column-major storage.
Definition: densemat.hpp:23
IntegrationRules RefinedIntRules(1, Quadrature1D::GaussLegendre)
A global object with all refined integration rules.
Definition: intrules.hpp:483
double kappa
Definition: ex24.cpp:54
bool Good() const
Return true if the command line options were parsed successfully.
Definition: optparser.hpp:159
Abstract parallel finite element space.
Definition: pfespace.hpp:28
STL namespace.
void SetPrintLevel(int print_lvl)
Definition: hypre.cpp:4010
IntegrationRules IntRules(0, Quadrature1D::GaussLegendre)
A global object with all integration rules (defined in intrules.cpp)
Definition: intrules.hpp:480
Geometry::Type GetGeomType() const
Returns the Geometry::Type of the reference element.
Definition: fe_base.hpp:320
The BoomerAMG solver in hypre.
Definition: hypre.hpp:1590
IntegrationPoint & IntPoint(int i)
Returns a reference to the i-th integration point.
Definition: intrules.hpp:256
Class for parallel linear form.
Definition: plinearform.hpp:26
void Parse()
Parse the command-line options. Note that this function expects all the options provided through the ...
Definition: optparser.cpp:151
char vishost[]
void mfem_error(const char *msg)
Function called when an error is encountered. Used by the macros MFEM_ABORT, MFEM_ASSERT, MFEM_VERIFY.
Definition: error.cpp:154
double b
Definition: lissajous.cpp:42
void UniformRefinement(int i, const DSTable &, int *, int *, int *)
Definition: mesh.cpp:10232
Data collection with VisIt I/O routines.
virtual void CalcShape(const IntegrationPoint &ip, Vector &shape) const =0
Evaluate the values of all shape functions of a scalar finite element in reference space at the given...
virtual const char * Name() const
Definition: fe_coll.hpp:80
double Weight()
Return the weight of the Jacobian matrix of the transformation at the currently set IntegrationPoint...
Definition: eltrans.hpp:131
void Print(std::ostream &out=mfem::out, int width=4) const
Prints array to stream with width elements per row.
Definition: array.cpp:23
HYPRE_BigInt GlobalTrueVSize() const
Definition: pfespace.hpp:281
void SetMaxIter(int max_iter)
Definition: hypre.cpp:4000
Abstract base class BilinearFormIntegrator.
Definition: bilininteg.hpp:24
Array< int > bdr_attributes
A list of all unique boundary attributes used by the Mesh.
Definition: mesh.hpp:275
int GetDim() const
Returns the reference space dimension for the finite element.
Definition: fe_base.hpp:311
PCG solver in hypre.
Definition: hypre.hpp:1215
Base class Coefficients that optionally depend on space and time. These are used by the BilinearFormI...
Definition: coefficient.hpp:41
Collection of finite elements from the same family in multiple dimensions. This class is used to matc...
Definition: fe_coll.hpp:26
virtual void Save() override
Save the collection and a VisIt root file.
void AddOption(bool *var, const char *enable_short_name, const char *enable_long_name, const char *disable_short_name, const char *disable_long_name, const char *description, bool required=false)
Add a boolean option and set &#39;var&#39; to receive the value. Enable/disable tags are used to set the bool...
Definition: optparser.hpp:82
void SetSize(int nsize)
Change the logical size of the array, keep existing entries.
Definition: array.hpp:687
HYPRE_Int HYPRE_BigInt
int GetDof() const
Returns the number of degrees of freedom in the finite element.
Definition: fe_base.hpp:323
virtual void Save(std::ostream &out) const
Definition: pgridfunc.cpp:909
int GetNE() const
Returns number of elements.
Definition: mesh.hpp:1086
double a
Definition: lissajous.cpp:41
NURBSExtension * NURBSext
Optional NURBS mesh extension.
Definition: mesh.hpp:277
Class for integration point with weight.
Definition: intrules.hpp:31
void ConnectBoundaries()
Definition: nurbs.cpp:2000
int dim
Definition: ex24.cpp:53
void SetPreconditioner(HypreSolver &precond)
Set the hypre solver to be used as a preconditioner.
Definition: hypre.cpp:4015
int GetNKV() const
Definition: nurbs.hpp:415
Class for parallel bilinear form.
Abstract class for hypre&#39;s solvers and preconditioners.
Definition: hypre.hpp:1102
int Size() const
Return the logical size of the array.
Definition: array.hpp:141
virtual double Eval(ElementTransformation &T, const IntegrationPoint &ip)=0
Evaluate the coefficient in the element described by T at the point ip.
Vector data type.
Definition: vector.hpp:58
Arbitrary order H1-conforming (continuous) finite elements.
Definition: fe_coll.hpp:259
void GetNodes(Vector &node_coord) const
Definition: mesh.cpp:8302
void Print(std::ostream &out=mfem::out) const override
Definition: pmesh.cpp:4825
Class for parallel grid function.
Definition: pgridfunc.hpp:32
void SetSize(int s)
Change the size of the DenseMatrix to s x s.
Definition: densemat.hpp:105
Wrapper for hypre&#39;s ParCSR matrix class.
Definition: hypre.hpp:343
Class for parallel meshes.
Definition: pmesh.hpp:32
int GetNP() const
Definition: nurbs.hpp:406
int GetOrder() const
Returns the order of the finite element. In the case of anisotropic orders, returns the maximum order...
Definition: fe_base.hpp:327
HYPRE_BigInt GetGlobalNumRows() const
Return the global number of rows.
Definition: hypre.hpp:635
virtual void RegisterField(const std::string &field_name, GridFunction *gf) override
Add a grid function to the collection and update the root file.