Actual source code: ex1.cxx
1: static char help[] = "Simple MOAB example\n\n";
3: #include <petscdmmoab.h>
4: #include "moab/ScdInterface.hpp"
6: typedef struct {
7: DM dm; /* DM implementation using the MOAB interface */
8: PetscLogEvent createMeshEvent;
9: /* Domain and mesh definition */
10: PetscInt dim;
11: char filename[PETSC_MAX_PATH_LEN];
12: char tagname[PETSC_MAX_PATH_LEN];
13: } AppCtx;
15: PetscErrorCode ProcessOptions(MPI_Comm comm, AppCtx *options)
16: {
18: PetscBool flg;
20: PetscStrcpy(options->filename, "");
21: PetscStrcpy(options->tagname, "petsc_tag");
22: options->dim = -1;
24: PetscOptionsBegin(comm, "", "MOAB example options", "DMMOAB");
25: PetscOptionsRangeInt("-dim", "The topological mesh dimension", "ex1.cxx", options->dim, &options->dim, NULL,PETSC_DECIDE,3);
26: PetscOptionsString("-filename", "The file containing the mesh", "ex1.cxx", options->filename, options->filename, sizeof(options->filename), NULL);
27: PetscOptionsString("-tagname", "The tag name from which to create a vector", "ex1.cxx", options->tagname, options->tagname, sizeof(options->tagname), &flg);
28: PetscOptionsEnd();
30: PetscLogEventRegister("CreateMesh", DM_CLASSID, &options->createMeshEvent);
31: return 0;
32: }
34: PetscErrorCode CreateMesh(MPI_Comm comm, AppCtx *user, DM *dm)
35: {
36: moab::Interface *iface=NULL;
37: moab::Tag tag=NULL;
38: moab::Tag ltog_tag=NULL;
39: moab::Range range;
40: PetscInt tagsize;
41: moab::ErrorCode merr;
43: PetscLogEventBegin(user->createMeshEvent,0,0,0,0);
44: DMMoabCreateMoab(comm, iface, <og_tag, &range, dm);
45: std::cout << "Created DMMoab using DMMoabCreateMoab." << std::endl;
46: DMMoabGetInterface(*dm, &iface);
48: // load file and get entities of requested or max dimension
49: if (strlen(user->filename) > 0) {
50: merr = iface->load_file(user->filename);MBERRNM(merr);
51: std::cout << "Read mesh from file " << user->filename << std::endl;
52: }
53: else {
54: // make a simple structured mesh
55: moab::ScdInterface *scdi;
56: merr = iface->query_interface(scdi);
58: moab::ScdBox *box;
59: merr = scdi->construct_box (moab::HomCoord(0,0,0), moab::HomCoord(5,5,5), NULL, 0, box);MBERRNM(merr);
60: user->dim = 3;
61: merr = iface->set_dimension(user->dim);MBERRNM(merr);
62: std::cout << "Created structured 5x5x5 mesh." << std::endl;
63: }
64: if (-1 == user->dim) {
65: moab::Range tmp_range;
66: merr = iface->get_entities_by_handle(0, tmp_range);MBERRNM(merr);
67: if (tmp_range.empty()) {
68: MBERRNM(moab::MB_FAILURE);
69: }
70: user->dim = iface->dimension_from_handle(*tmp_range.rbegin());
71: }
72: merr = iface->get_entities_by_dimension(0, user->dim, range);MBERRNM(merr);
73: DMMoabSetLocalVertices(*dm, &range);
75: // get the requested tag and create if necessary
76: std::cout << "Creating tag with name: " << user->tagname << ";\n";
77: merr = iface->tag_get_handle(user->tagname, 1, moab::MB_TYPE_DOUBLE, tag, moab::MB_TAG_CREAT | moab::MB_TAG_DENSE);MBERRNM(merr);
78: {
79: // initialize new tag with gids
80: std::vector<double> tag_vals(range.size());
81: merr = iface->tag_get_data(ltog_tag, range, tag_vals.data());MBERRNM(merr); // read them into ints
82: double *dval = tag_vals.data(); int *ival = reinterpret_cast<int*>(dval); // "stretch" them into doubles, from the end
83: for (int i = tag_vals.size()-1; i >= 0; i--) dval[i] = ival[i];
84: merr = iface->tag_set_data(tag, range, tag_vals.data());MBERRNM(merr); // write them into doubles
85: }
86: merr = iface->tag_get_length(tag, tagsize);MBERRNM(merr);
88: DMSetUp(*dm);
90: // create the dmmoab and initialize its data
91: PetscObjectSetName((PetscObject) *dm, "MOAB mesh");
92: PetscLogEventEnd(user->createMeshEvent,0,0,0,0);
93: user->dm = *dm;
94: return 0;
95: }
97: int main(int argc, char **argv)
98: {
99: AppCtx user; /* user-defined work context */
100: moab::ErrorCode merr;
101: Vec vec;
102: moab::Interface* mbImpl=NULL;
103: moab::Tag datatag=NULL;
105: PetscInitialize(&argc, &argv, NULL,help);
106: ProcessOptions(PETSC_COMM_WORLD, &user);
108: CreateMesh(PETSC_COMM_WORLD, &user, &user.dm); /* create the MOAB dm and the mesh */
110: DMMoabGetInterface(user.dm, &mbImpl);
111: merr = mbImpl->tag_get_handle(user.tagname, datatag);MBERRNM(merr);
112: DMMoabCreateVector(user.dm, datatag, NULL, PETSC_TRUE, PETSC_FALSE,&vec); /* create a vec from user-input tag */
114: std::cout << "Created VecMoab from existing tag." << std::endl;
115: VecDestroy(&vec);
116: std::cout << "Destroyed VecMoab." << std::endl;
117: DMDestroy(&user.dm);
118: std::cout << "Destroyed DMMoab." << std::endl;
119: PetscFinalize();
120: return 0;
121: }
123: /*TEST
125: build:
126: requires: moab
128: test:
130: TEST*/