Actual source code: ex3.cxx

  1: static char help[] = "Create a box mesh with DMMoab and test defining a tag on the mesh\n\n";

  3: #include <petscdmmoab.h>

  5: typedef struct {
  6:   DM            dm;    /* DM implementation using the MOAB interface */
  7:   PetscBool     debug; /* The debugging level */
  8:   PetscLogEvent createMeshEvent;
  9:   /* Domain and mesh definition */
 10:   PetscInt  dim;                             /* The topological mesh dimension */
 11:   PetscInt  nele;                            /* Elements in each dimension */
 12:   PetscInt  degree;                          /* Degree of refinement */
 13:   PetscBool simplex;                         /* Use simplex elements */
 14:   PetscInt  nlevels;                         /* Number of levels in mesh hierarchy */
 15:   PetscInt  nghost;                          /* Number of ghost layers in the mesh */
 16:   char      input_file[PETSC_MAX_PATH_LEN];  /* Import mesh from file */
 17:   char      output_file[PETSC_MAX_PATH_LEN]; /* Output mesh file name */
 18:   PetscBool write_output;                    /* Write output mesh and data to file */
 19: } AppCtx;

 21: PetscErrorCode ProcessOptions(MPI_Comm comm, AppCtx *options)
 22: {
 23:   PetscFunctionBegin;
 24:   options->debug         = PETSC_FALSE;
 25:   options->nlevels       = 1;
 26:   options->nghost        = 1;
 27:   options->dim           = 2;
 28:   options->nele          = 5;
 29:   options->degree        = 2;
 30:   options->simplex       = PETSC_FALSE;
 31:   options->write_output  = PETSC_FALSE;
 32:   options->input_file[0] = '\0';
 33:   PetscCall(PetscStrncpy(options->output_file, "ex3.h5m", sizeof(options->output_file)));

 35:   PetscOptionsBegin(comm, "", "Uniform Mesh Refinement Options", "DMMOAB");
 36:   PetscCall(PetscOptionsBool("-debug", "Enable debug messages", "ex2.cxx", options->debug, &options->debug, NULL));
 37:   PetscCall(PetscOptionsRangeInt("-dim", "The topological mesh dimension", "ex3.cxx", options->dim, &options->dim, NULL, 0, 3));
 38:   PetscCall(PetscOptionsBoundedInt("-n", "The number of elements in each dimension", "ex3.cxx", options->nele, &options->nele, NULL, 1));
 39:   PetscCall(PetscOptionsBoundedInt("-levels", "Number of levels in the hierarchy", "ex3.cxx", options->nlevels, &options->nlevels, NULL, 0));
 40:   PetscCall(PetscOptionsBoundedInt("-degree", "Number of degrees at each level of refinement", "ex3.cxx", options->degree, &options->degree, NULL, 0));
 41:   PetscCall(PetscOptionsBoundedInt("-ghost", "Number of ghost layers in the mesh", "ex3.cxx", options->nghost, &options->nghost, NULL, 0));
 42:   PetscCall(PetscOptionsBool("-simplex", "Create simplices instead of tensor product elements", "ex3.cxx", options->simplex, &options->simplex, NULL));
 43:   PetscCall(PetscOptionsString("-input", "The input mesh file", "ex3.cxx", options->input_file, options->input_file, sizeof(options->input_file), NULL));
 44:   PetscCall(PetscOptionsString("-io", "Write out the mesh and solution that is defined on it (Default H5M format)", "ex3.cxx", options->output_file, options->output_file, sizeof(options->output_file), &options->write_output));
 45:   PetscOptionsEnd();

 47:   PetscCall(PetscLogEventRegister("CreateMesh", DM_CLASSID, &options->createMeshEvent));
 48:   PetscFunctionReturn(PETSC_SUCCESS);
 49: }

 51: PetscErrorCode CreateMesh(MPI_Comm comm, AppCtx *user)
 52: {
 53:   size_t      len;
 54:   PetscMPIInt rank;

 56:   PetscFunctionBegin;
 57:   PetscCall(PetscLogEventBegin(user->createMeshEvent, 0, 0, 0, 0));
 58:   PetscCallMPI(MPI_Comm_rank(comm, &rank));
 59:   PetscCall(PetscStrlen(user->input_file, &len));
 60:   if (len) {
 61:     if (user->debug) PetscCall(PetscPrintf(comm, "Loading mesh from file: %s and creating the coarse level DM object.\n", user->input_file));
 62:     PetscCall(DMMoabLoadFromFile(comm, user->dim, user->nghost, user->input_file, "", &user->dm));
 63:   } else {
 64:     if (user->debug)
 65:       PetscCall(PetscPrintf(comm, "Creating a %" PetscInt_FMT "-dimensional structured %s mesh of %" PetscInt_FMT "x%" PetscInt_FMT "x%" PetscInt_FMT " in memory and creating a DM object.\n", user->dim, user->simplex ? "simplex" : "regular", user->nele,
 66:                             user->nele, user->nele));
 67:     PetscCall(DMMoabCreateBoxMesh(comm, user->dim, user->simplex, NULL, user->nele, user->nghost, &user->dm));
 68:   }
 69:   PetscCall(PetscObjectSetName((PetscObject)user->dm, "Coarse Mesh"));
 70:   PetscCall(PetscLogEventEnd(user->createMeshEvent, 0, 0, 0, 0));
 71:   PetscFunctionReturn(PETSC_SUCCESS);
 72: }

 74: int main(int argc, char **argv)
 75: {
 76:   AppCtx    user; /* user-defined work context */
 77:   MPI_Comm  comm;
 78:   PetscInt  i;
 79:   Mat       R;
 80:   DM       *dmhierarchy;
 81:   PetscInt *degrees;
 82:   PetscBool createR;

 84:   PetscFunctionBeginUser;
 85:   PetscCall(PetscInitialize(&argc, &argv, NULL, help));
 86:   comm    = PETSC_COMM_WORLD;
 87:   createR = PETSC_FALSE;

 89:   PetscCall(ProcessOptions(comm, &user));
 90:   PetscCall(CreateMesh(comm, &user));
 91:   PetscCall(DMSetFromOptions(user.dm));

 93:   /* SetUp the data structures for DMMOAB */
 94:   PetscCall(DMSetUp(user.dm));

 96:   PetscCall(PetscMalloc(sizeof(DM) * (user.nlevels + 1), &dmhierarchy));
 97:   for (i = 0; i <= user.nlevels; i++) dmhierarchy[i] = NULL;

 99:   // coarsest grid = 0
100:   // finest grid = nlevels
101:   dmhierarchy[0] = user.dm;
102:   PetscCall(PetscObjectReference((PetscObject)user.dm));

104:   if (user.nlevels) {
105:     PetscCall(PetscMalloc1(user.nlevels, &degrees));
106:     for (i = 0; i < user.nlevels; i++) degrees[i] = user.degree;
107:     if (user.debug) PetscCall(PetscPrintf(comm, "Generate the MOAB mesh hierarchy with %" PetscInt_FMT " levels.\n", user.nlevels));
108:     PetscCall(DMMoabGenerateHierarchy(user.dm, user.nlevels, degrees));

110:     PetscBool usehierarchy = PETSC_FALSE;
111:     if (usehierarchy) PetscCall(DMRefineHierarchy(user.dm, user.nlevels, &dmhierarchy[1]));
112:     else {
113:       if (user.debug) {
114:         PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Level %" PetscInt_FMT "\n", 0));
115:         PetscCall(DMView(user.dm, 0));
116:       }
117:       for (i = 1; i <= user.nlevels; i++) {
118:         if (user.debug) PetscCall(PetscPrintf(PETSC_COMM_WORLD, "Level %" PetscInt_FMT "\n", i));
119:         PetscCall(DMRefine(dmhierarchy[i - 1], MPI_COMM_NULL, &dmhierarchy[i]));
120:         if (createR) PetscCall(DMCreateInterpolation(dmhierarchy[i - 1], dmhierarchy[i], &R, NULL));
121:         if (user.debug) {
122:           PetscCall(DMView(dmhierarchy[i], 0));
123:           if (createR) PetscCall(MatView(R, 0));
124:         }
125:         /* Solvers could now set operator "R" to the multigrid PC object for level i
126:             PCMGSetInterpolation(pc,i,R)
127:         */
128:         if (createR) PetscCall(MatDestroy(&R));
129:       }
130:     }
131:   }

133:   if (user.write_output) {
134:     if (user.debug) PetscCall(PetscPrintf(comm, "Output mesh hierarchy to file: %s.\n", user.output_file));
135:     PetscCall(DMMoabOutput(dmhierarchy[user.nlevels], (const char *)user.output_file, ""));
136:   }

138:   for (i = 0; i <= user.nlevels; i++) PetscCall(DMDestroy(&dmhierarchy[i]));
139:   PetscCall(PetscFree(degrees));
140:   PetscCall(PetscFree(dmhierarchy));
141:   PetscCall(DMDestroy(&user.dm));
142:   PetscCall(PetscFinalize());
143:   return 0;
144: }

146: /*TEST

148:      build:
149:        requires: moab !complex

151:      test:
152:        args: -debug -n 2 -dim 2 -levels 2 -simplex
153:        filter:  grep -v "DM_0x"

155:      test:
156:        args: -debug -n 2 -dim 3 -levels 2
157:        filter:  grep -v "DM_0x"
158:        suffix: 1_2

160:      test:
161:        args: -debug -n 2 -dim 3 -ghost 1 -levels 2
162:        filter:  grep -v "DM_0x"
163:        nsize: 2
164:        suffix: 2_1

166: TEST*/