xref: /petsc/src/dm/impls/plex/tutorials/ex1.c (revision 0cae81350c4a214d95cc256bf0d00cd523120bb5)
1c4762a1bSJed Brown static char help[] = "Define a simple field over the mesh\n\n";
2c4762a1bSJed Brown 
3c4762a1bSJed Brown #include <petscdmplex.h>
4c4762a1bSJed Brown 
5d71ae5a4SJacob Faibussowitsch int main(int argc, char **argv)
6d71ae5a4SJacob Faibussowitsch {
730602db0SMatthew G. Knepley   DM           dm;
8c4762a1bSJed Brown   Vec          u;
9c4762a1bSJed Brown   PetscSection section;
10c4762a1bSJed Brown   PetscViewer  viewer;
1130602db0SMatthew G. Knepley   PetscInt     dim, numFields, numBC, i;
12c4762a1bSJed Brown   PetscInt     numComp[3];
13c4762a1bSJed Brown   PetscInt     numDof[12];
14c4762a1bSJed Brown   PetscInt     bcField[1];
15c4762a1bSJed Brown   IS           bcPointIS[1];
16c4762a1bSJed Brown 
17327415f7SBarry Smith   PetscFunctionBeginUser;
189566063dSJacob Faibussowitsch   PetscCall(PetscInitialize(&argc, &argv, NULL, help));
19c4762a1bSJed Brown   /* Create a mesh */
209566063dSJacob Faibussowitsch   PetscCall(DMCreate(PETSC_COMM_WORLD, &dm));
219566063dSJacob Faibussowitsch   PetscCall(DMSetType(dm, DMPLEX));
229566063dSJacob Faibussowitsch   PetscCall(DMSetFromOptions(dm));
239566063dSJacob Faibussowitsch   PetscCall(DMViewFromOptions(dm, NULL, "-dm_view"));
249566063dSJacob Faibussowitsch   PetscCall(DMGetDimension(dm, &dim));
25c4762a1bSJed Brown   /* Create a scalar field u, a vector field v, and a surface vector field w */
26c4762a1bSJed Brown   numFields  = 3;
27c4762a1bSJed Brown   numComp[0] = 1;
28c4762a1bSJed Brown   numComp[1] = dim;
29c4762a1bSJed Brown   numComp[2] = dim - 1;
30c4762a1bSJed Brown   for (i = 0; i < numFields * (dim + 1); ++i) numDof[i] = 0;
31c4762a1bSJed Brown   /* Let u be defined on vertices */
32c4762a1bSJed Brown   numDof[0 * (dim + 1) + 0] = 1;
33c4762a1bSJed Brown   /* Let v be defined on cells */
34c4762a1bSJed Brown   numDof[1 * (dim + 1) + dim] = dim;
35c4762a1bSJed Brown   /* Let w be defined on faces */
36c4762a1bSJed Brown   numDof[2 * (dim + 1) + dim - 1] = dim - 1;
37c4762a1bSJed Brown   /* Setup boundary conditions */
38c4762a1bSJed Brown   numBC = 1;
39c4762a1bSJed Brown   /* Prescribe a Dirichlet condition on u on the boundary
40c4762a1bSJed Brown        Label "marker" is made by the mesh creation routine */
41c4762a1bSJed Brown   bcField[0] = 0;
429566063dSJacob Faibussowitsch   PetscCall(DMGetStratumIS(dm, "marker", 1, &bcPointIS[0]));
43c4762a1bSJed Brown   /* Create a PetscSection with this data layout */
449566063dSJacob Faibussowitsch   PetscCall(DMSetNumFields(dm, numFields));
459566063dSJacob Faibussowitsch   PetscCall(DMPlexCreateSection(dm, NULL, numComp, numDof, numBC, bcField, NULL, bcPointIS, NULL, &section));
469566063dSJacob Faibussowitsch   PetscCall(ISDestroy(&bcPointIS[0]));
47c4762a1bSJed Brown   /* Name the Field variables */
489566063dSJacob Faibussowitsch   PetscCall(PetscSectionSetFieldName(section, 0, "u"));
499566063dSJacob Faibussowitsch   PetscCall(PetscSectionSetFieldName(section, 1, "v"));
509566063dSJacob Faibussowitsch   PetscCall(PetscSectionSetFieldName(section, 2, "w"));
51*0cae8135SMatthew G. Knepley   PetscCall(PetscSectionViewFromOptions(section, NULL, "-mysection_view"));
52c4762a1bSJed Brown   /* Tell the DM to use this data layout */
539566063dSJacob Faibussowitsch   PetscCall(DMSetLocalSection(dm, section));
54c4762a1bSJed Brown   /* Create a Vec with this layout and view it */
559566063dSJacob Faibussowitsch   PetscCall(DMGetGlobalVector(dm, &u));
569566063dSJacob Faibussowitsch   PetscCall(PetscViewerCreate(PETSC_COMM_WORLD, &viewer));
579566063dSJacob Faibussowitsch   PetscCall(PetscViewerSetType(viewer, PETSCVIEWERVTK));
589566063dSJacob Faibussowitsch   PetscCall(PetscViewerFileSetName(viewer, "sol.vtu"));
599566063dSJacob Faibussowitsch   PetscCall(VecView(u, viewer));
609566063dSJacob Faibussowitsch   PetscCall(PetscViewerDestroy(&viewer));
619566063dSJacob Faibussowitsch   PetscCall(DMRestoreGlobalVector(dm, &u));
62c4762a1bSJed Brown   /* Cleanup */
639566063dSJacob Faibussowitsch   PetscCall(PetscSectionDestroy(&section));
649566063dSJacob Faibussowitsch   PetscCall(DMDestroy(&dm));
659566063dSJacob Faibussowitsch   PetscCall(PetscFinalize());
66b122ec5aSJacob Faibussowitsch   return 0;
67c4762a1bSJed Brown }
68c4762a1bSJed Brown 
69c4762a1bSJed Brown /*TEST
70c4762a1bSJed Brown 
71c4762a1bSJed Brown   test:
72c4762a1bSJed Brown     suffix: 0
73c4762a1bSJed Brown     requires: triangle
74*0cae8135SMatthew G. Knepley     args: -mysection_view -info :~sys,mat
75*0cae8135SMatthew G. Knepley 
76c4762a1bSJed Brown   test:
77c4762a1bSJed Brown     suffix: 1
78c4762a1bSJed Brown     requires: ctetgen
79*0cae8135SMatthew G. Knepley     args: -dm_plex_dim 3 -mysection_view -info :~sys,mat
80*0cae8135SMatthew G. Knepley 
81*0cae8135SMatthew G. Knepley   test:
82*0cae8135SMatthew G. Knepley     suffix: filter_0
83*0cae8135SMatthew G. Knepley     args: -dm_plex_simplex 0 -dm_plex_box_faces 3,3 -dm_plex_label_lower 0,1,2,3,4,6 \
84*0cae8135SMatthew G. Knepley       -dm_refine 1 -dm_plex_transform_type transform_filter -dm_plex_transform_active lower \
85*0cae8135SMatthew G. Knepley       -dm_view
86*0cae8135SMatthew G. Knepley 
87*0cae8135SMatthew G. Knepley   test:
88*0cae8135SMatthew G. Knepley     suffix: submesh_0
89*0cae8135SMatthew G. Knepley     requires: triangle
90*0cae8135SMatthew G. Knepley     args: -dm_plex_label_middle 9,12,15,23,31 -dm_plex_submesh middle -dm_view
91c4762a1bSJed Brown 
92c4762a1bSJed Brown TEST*/
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