1 static char help[] = "Simple MOAB example\n\n"; 2 3 #include <petscdmmoab.h> 4 #include "moab/ScdInterface.hpp" 5 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; 14 15 PetscErrorCode ProcessOptions(MPI_Comm comm, AppCtx *options) 16 { 17 PetscBool flg; 18 19 PetscFunctionBegin; 20 PetscCall(PetscStrncpy(options->filename, "", sizeof(options->filename))); 21 PetscCall(PetscStrncpy(options->tagname, "petsc_tag", sizeof(options->tagname))); 22 options->dim = -1; 23 24 PetscOptionsBegin(comm, "", "MOAB example options", "DMMOAB"); 25 PetscCall(PetscOptionsRangeInt("-dim", "The topological mesh dimension", "ex1.cxx", options->dim, &options->dim, NULL, PETSC_DECIDE, 3)); 26 PetscCall(PetscOptionsString("-filename", "The file containing the mesh", "ex1.cxx", options->filename, options->filename, sizeof(options->filename), NULL)); 27 PetscCall(PetscOptionsString("-tagname", "The tag name from which to create a vector", "ex1.cxx", options->tagname, options->tagname, sizeof(options->tagname), &flg)); 28 PetscOptionsEnd(); 29 30 PetscCall(PetscLogEventRegister("CreateMesh", DM_CLASSID, &options->createMeshEvent)); 31 PetscFunctionReturn(PETSC_SUCCESS); 32 } 33 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; 42 43 PetscFunctionBegin; 44 PetscCall(PetscLogEventBegin(user->createMeshEvent, 0, 0, 0, 0)); 45 PetscCall(DMMoabCreateMoab(comm, iface, <og_tag, &range, dm)); 46 std::cout << "Created DMMoab using DMMoabCreateMoab." << std::endl; 47 PetscCall(DMMoabGetInterface(*dm, &iface)); 48 49 // load file and get entities of requested or max dimension 50 if (strlen(user->filename) > 0) { 51 merr = iface->load_file(user->filename); 52 MBERRNM(merr); 53 std::cout << "Read mesh from file " << user->filename << std::endl; 54 } else { 55 // make a simple structured mesh 56 moab::ScdInterface *scdi; 57 merr = iface->query_interface(scdi); 58 59 moab::ScdBox *box; 60 merr = scdi->construct_box(moab::HomCoord(0, 0, 0), moab::HomCoord(5, 5, 5), NULL, 0, box); 61 MBERRNM(merr); 62 user->dim = 3; 63 merr = iface->set_dimension(user->dim); 64 MBERRNM(merr); 65 std::cout << "Created structured 5x5x5 mesh." << std::endl; 66 } 67 if (-1 == user->dim) { 68 moab::Range tmp_range; 69 merr = iface->get_entities_by_handle(0, tmp_range); 70 MBERRNM(merr); 71 if (tmp_range.empty()) MBERRNM(moab::MB_FAILURE); 72 user->dim = iface->dimension_from_handle(*tmp_range.rbegin()); 73 } 74 merr = iface->get_entities_by_dimension(0, user->dim, range); 75 MBERRNM(merr); 76 PetscCall(DMMoabSetLocalVertices(*dm, &range)); 77 78 // get the requested tag and create if necessary 79 std::cout << "Creating tag with name: " << user->tagname << ";\n"; 80 merr = iface->tag_get_handle(user->tagname, 1, moab::MB_TYPE_DOUBLE, tag, moab::MB_TAG_CREAT | moab::MB_TAG_DENSE); 81 MBERRNM(merr); 82 { 83 // initialize new tag with gids 84 std::vector<double> tag_vals(range.size()); 85 merr = iface->tag_get_data(ltog_tag, range, tag_vals.data()); 86 MBERRNM(merr); // read them into ints 87 double *dval = tag_vals.data(); 88 int *ival = reinterpret_cast<int *>(dval); // "stretch" them into doubles, from the end 89 for (int i = tag_vals.size() - 1; i >= 0; i--) dval[i] = ival[i]; 90 merr = iface->tag_set_data(tag, range, tag_vals.data()); 91 MBERRNM(merr); // write them into doubles 92 } 93 merr = iface->tag_get_length(tag, tagsize); 94 MBERRNM(merr); 95 96 PetscCall(DMSetUp(*dm)); 97 98 // create the dmmoab and initialize its data 99 PetscCall(PetscObjectSetName((PetscObject)*dm, "MOAB mesh")); 100 PetscCall(PetscLogEventEnd(user->createMeshEvent, 0, 0, 0, 0)); 101 user->dm = *dm; 102 PetscFunctionReturn(PETSC_SUCCESS); 103 } 104 105 int main(int argc, char **argv) 106 { 107 AppCtx user; /* user-defined work context */ 108 moab::ErrorCode merr; 109 Vec vec; 110 moab::Interface *mbImpl = NULL; 111 moab::Tag datatag = NULL; 112 113 PetscFunctionBeginUser; 114 PetscCall(PetscInitialize(&argc, &argv, NULL, help)); 115 PetscCall(ProcessOptions(PETSC_COMM_WORLD, &user)); 116 117 PetscCall(CreateMesh(PETSC_COMM_WORLD, &user, &user.dm)); /* create the MOAB dm and the mesh */ 118 119 PetscCall(DMMoabGetInterface(user.dm, &mbImpl)); 120 merr = mbImpl->tag_get_handle(user.tagname, datatag); 121 MBERRNM(merr); 122 PetscCall(DMMoabCreateVector(user.dm, datatag, NULL, PETSC_TRUE, PETSC_FALSE, &vec)); /* create a vec from user-input tag */ 123 124 std::cout << "Created VecMoab from existing tag." << std::endl; 125 PetscCall(VecDestroy(&vec)); 126 std::cout << "Destroyed VecMoab." << std::endl; 127 PetscCall(DMDestroy(&user.dm)); 128 std::cout << "Destroyed DMMoab." << std::endl; 129 PetscCall(PetscFinalize()); 130 return 0; 131 } 132 133 /*TEST 134 135 build: 136 requires: moab !complex 137 138 test: 139 140 TEST*/ 141