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:   PetscBool     simplex;                        /* Use simplex elements */
 13:   PetscBool     interlace;
 14:   char          input_file[PETSC_MAX_PATH_LEN];   /* Import mesh from file */
 15:   char          output_file[PETSC_MAX_PATH_LEN];   /* Output mesh file name */
 16:   PetscBool     write_output;                        /* Write output mesh and data to file */
 17:   PetscInt      nfields;         /* Number of fields */
 18:   char          *fieldnames[PETSC_MAX_PATH_LEN]; /* Name of a defined field on the mesh */
 19: } AppCtx;

 23: PetscErrorCode ProcessOptions(MPI_Comm comm, AppCtx *options)
 24: {
 26:   PetscBool      flg;

 29:   options->debug             = PETSC_FALSE;
 30:   options->dim               = 2;
 31:   options->nele              = 5;
 32:   options->nfields           = 256;
 33:   options->simplex           = PETSC_FALSE;
 34:   options->write_output      = PETSC_FALSE;
 35:   options->interlace         = PETSC_FALSE;
 36:   options->input_file[0]     = '\0';
 37:   PetscStrcpy(options->output_file,"ex2.h5m");

 39:   PetscOptionsBegin(comm, "", "Meshing Problem Options", "DMMOAB");
 40:   PetscOptionsBool("-debug", "Enable debug messages", "ex2.c", options->debug, &options->debug, NULL);
 41:   PetscOptionsBool("-interlace", "Use interlaced arrangement for the field data", "ex2.c", options->interlace, &options->interlace, NULL);
 42:   PetscOptionsBool("-simplex", "Create simplices instead of tensor product elements", "ex2.c", options->simplex, &options->simplex, NULL);
 43:   PetscOptionsInt("-dim", "The topological mesh dimension", "ex2.c", options->dim, &options->dim, NULL);
 44:   PetscOptionsInt("-n", "The number of elements in each dimension", "ex2.c", options->nele, &options->nele, NULL);
 45:   PetscOptionsString("-meshfile", "The input mesh file", "ex2.c", options->input_file, options->input_file, PETSC_MAX_PATH_LEN, NULL);
 46:   PetscOptionsString("-out", "Write out the mesh and solution that is defined on it (Default H5M format)", "ex2.c", options->output_file, options->output_file, PETSC_MAX_PATH_LEN, &options->write_output);
 47:   PetscOptionsStringArray("-fields", "The list of names of the field variables", "ex2.c", options->fieldnames,&options->nfields, &flg);
 48:   PetscOptionsEnd();

 50:   if (options->debug) PetscPrintf(comm, "Total number of fields: %D.\n",options->nfields);
 51:   if (!flg) { /* if no field names were given by user, assign a default */
 52:     options->nfields = 1;
 53:     PetscStrallocpy("TestEX2Var",&options->fieldnames[0]);
 54:   }

 56:   PetscLogEventRegister("CreateMesh",          DM_CLASSID,   &options->createMeshEvent);
 57:   return(0);
 58: };

 62: PetscErrorCode CreateMesh(MPI_Comm comm, AppCtx *user)
 63: {
 64:   PetscInt       i;
 65:   size_t         len;
 66:   PetscMPIInt    rank;

 70:   PetscLogEventBegin(user->createMeshEvent,0,0,0,0);
 71:   MPI_Comm_rank(comm, &rank);
 72:   PetscStrlen(user->input_file, &len);
 73:   if (len) {
 74:     if (user->debug) PetscPrintf(comm, "Loading mesh from file: %s and creating a DM object.\n",user->input_file);
 75:     DMMoabLoadFromFile(comm, user->dim, user->input_file, "", &user->dm);
 76:   }
 77:   else {
 78:     if (user->debug) {
 79:       PetscPrintf(comm, "Creating a %D-dimensional structured %s mesh of %Dx%Dx%D in memory and creating a DM object.\n",user->dim,(user->simplex?"simplex":"regular"),user->nele,user->nele,user->nele);
 80:     }
 81:     DMMoabCreateBoxMesh(comm, user->dim, user->simplex, NULL, user->nele, 1, &user->dm);
 82:   }

 84:   if (user->debug) {
 85:     PetscPrintf(comm, "Setting field names to DM: \n");
 86:     for (i=0; i<user->nfields; i++)
 87:       PetscPrintf(comm, "\t Field{%D} = %s.\n",i,user->fieldnames[i]);
 88:   }
 89:   DMMoabSetFieldNames(user->dm, user->nfields, (const char**)user->fieldnames);
 90:   PetscObjectSetName((PetscObject)user->dm, "Structured Mesh");
 91:   PetscLogEventEnd(user->createMeshEvent,0,0,0,0);
 92:   return(0);
 93: }

 97: int main(int argc, char **argv)
 98: {
 99:   AppCtx         user;                 /* user-defined work context */
100:   PetscRandom    rctx;
101:   Vec            solution;
102:   Mat            system;
103:   MPI_Comm       comm;
104:   PetscInt       i;

107:   PetscInitialize(&argc, &argv, NULL, help);
108:   comm = PETSC_COMM_WORLD;
109:   ProcessOptions(comm, &user);
110:   CreateMesh(comm, &user);

112:   /* set block size */
113:   DMMoabSetBlockSize(user.dm, (user.interlace?user.nfields:1));
114:   DMSetMatType(user.dm,MATAIJ);

116:   DMSetFromOptions(user.dm);

118:   /* SetUp the data structures for DMMOAB */
119:   DMSetUp(user.dm);

121:   if (user.debug) PetscPrintf(comm, "Creating a global vector defined on DM and setting random data.\n");
122:   DMCreateGlobalVector(user.dm,&solution);
123:   PetscRandomCreate(comm,&rctx);
124:   PetscRandomSetType(rctx,PETSCRAND48);
125:   VecSetRandom(solution,rctx);

127:   /* test if matrix allocation for the prescribed matrix type is done correctly */
128:   if (user.debug) PetscPrintf(comm, "Creating a global matrix defined on DM with the right block structure.\n");
129:   DMCreateMatrix(user.dm,&system);

131:   if (user.write_output) {
132:     DMMoabSetGlobalFieldVector(user.dm, solution);
133:     if (user.debug) PetscPrintf(comm, "Output mesh and associated field data to file: %s.\n",user.output_file);
134:     DMMoabOutput(user.dm,(const char*)user.output_file,"");
135:   }

137:   if (user.fieldnames) {
138:     for(i=0; i<user.nfields; i++) {
139:       PetscFree(user.fieldnames[i]);
140:     }
141:   }
142:   PetscRandomDestroy(&rctx);
143:   VecDestroy(&solution);
144:   MatDestroy(&system);
145:   DMDestroy(&user.dm);
146:   PetscFinalize();
147:   return 0;
148: }