xref: /petsc/src/dm/impls/moab/tests/ex1.cxx (revision ccb4e88a40f0b86eaeca07ff64c64e4de2fae686)
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   PetscErrorCode ierr;
18   PetscBool      flg;
19 
20   PetscFunctionBegin;
21   ierr = PetscStrcpy(options->filename, "");CHKERRQ(ierr);
22   ierr = PetscStrcpy(options->tagname, "petsc_tag");CHKERRQ(ierr);
23   options->dim = -1;
24 
25   ierr = PetscOptionsBegin(comm, "", "MOAB example options", "DMMOAB");CHKERRQ(ierr);
26   ierr = PetscOptionsRangeInt("-dim", "The topological mesh dimension", "ex1.cxx", options->dim, &options->dim, NULL,PETSC_DECIDE,3);CHKERRQ(ierr);
27   ierr = PetscOptionsString("-filename", "The file containing the mesh", "ex1.cxx", options->filename, options->filename, sizeof(options->filename), NULL);CHKERRQ(ierr);
28   ierr = PetscOptionsString("-tagname", "The tag name from which to create a vector", "ex1.cxx", options->tagname, options->tagname, sizeof(options->tagname), &flg);CHKERRQ(ierr);
29   ierr = PetscOptionsEnd();CHKERRQ(ierr);
30 
31   ierr = PetscLogEventRegister("CreateMesh",          DM_CLASSID,   &options->createMeshEvent);CHKERRQ(ierr);
32   PetscFunctionReturn(0);
33 }
34 
35 PetscErrorCode CreateMesh(MPI_Comm comm, AppCtx *user, DM *dm)
36 {
37   moab::Interface *iface=NULL;
38   moab::Tag tag=NULL;
39   moab::Tag ltog_tag=NULL;
40   moab::Range range;
41   PetscInt tagsize;
42   moab::ErrorCode merr;
43   PetscErrorCode ierr;
44 
45   PetscFunctionBegin;
46   ierr = PetscLogEventBegin(user->createMeshEvent,0,0,0,0);CHKERRQ(ierr);
47   ierr = DMMoabCreateMoab(comm, iface, &ltog_tag, &range, dm);CHKERRQ(ierr);
48   std::cout << "Created DMMoab using DMMoabCreateMoab." << std::endl;
49   ierr = DMMoabGetInterface(*dm, &iface);CHKERRQ(ierr);
50 
51     // load file and get entities of requested or max dimension
52   if (strlen(user->filename) > 0) {
53     merr = iface->load_file(user->filename);MBERRNM(merr);
54     std::cout << "Read mesh from file " << user->filename << std::endl;
55   }
56   else {
57       // make a simple structured mesh
58     moab::ScdInterface *scdi;
59     merr = iface->query_interface(scdi);
60 
61     moab::ScdBox *box;
62     merr = scdi->construct_box (moab::HomCoord(0,0,0), moab::HomCoord(5,5,5), NULL, 0, box);MBERRNM(merr);
63     user->dim = 3;
64     merr = iface->set_dimension(user->dim);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);MBERRNM(merr);
70     if (tmp_range.empty()) {
71       MBERRNM(moab::MB_FAILURE);
72     }
73     user->dim = iface->dimension_from_handle(*tmp_range.rbegin());
74   }
75   merr = iface->get_entities_by_dimension(0, user->dim, range);MBERRNM(merr);
76   ierr = DMMoabSetLocalVertices(*dm, &range);CHKERRQ(ierr);
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);MBERRNM(merr);
81   {
82       // initialize new tag with gids
83     std::vector<double> tag_vals(range.size());
84     merr = iface->tag_get_data(ltog_tag, range, tag_vals.data());MBERRNM(merr); // read them into ints
85     double *dval = tag_vals.data(); int *ival = reinterpret_cast<int*>(dval); // "stretch" them into doubles, from the end
86     for (int i = tag_vals.size()-1; i >= 0; i--) dval[i] = ival[i];
87     merr = iface->tag_set_data(tag, range, tag_vals.data());MBERRNM(merr); // write them into doubles
88   }
89   merr = iface->tag_get_length(tag, tagsize);MBERRNM(merr);
90 
91   ierr = DMSetUp(*dm);CHKERRQ(ierr);
92 
93     // create the dmmoab and initialize its data
94   ierr = PetscObjectSetName((PetscObject) *dm, "MOAB mesh");CHKERRQ(ierr);
95   ierr = PetscLogEventEnd(user->createMeshEvent,0,0,0,0);CHKERRQ(ierr);
96   user->dm = *dm;
97   PetscFunctionReturn(0);
98 }
99 
100 int main(int argc, char **argv)
101 {
102   AppCtx            user;                 /* user-defined work context */
103   moab::ErrorCode   merr;
104   PetscErrorCode    ierr;
105   Vec               vec;
106   moab::Interface*  mbImpl=NULL;
107   moab::Tag         datatag=NULL;
108 
109   ierr = PetscInitialize(&argc, &argv, NULL,help);if (ierr) return ierr;
110   ierr = ProcessOptions(PETSC_COMM_WORLD, &user);CHKERRQ(ierr);
111 
112   ierr = CreateMesh(PETSC_COMM_WORLD, &user, &user.dm);CHKERRQ(ierr); /* create the MOAB dm and the mesh */
113 
114   ierr = DMMoabGetInterface(user.dm, &mbImpl);CHKERRQ(ierr);
115   merr = mbImpl->tag_get_handle(user.tagname, datatag);MBERRNM(merr);
116   ierr = DMMoabCreateVector(user.dm, datatag, NULL, PETSC_TRUE, PETSC_FALSE,&vec);CHKERRQ(ierr); /* create a vec from user-input tag */
117 
118   std::cout << "Created VecMoab from existing tag." << std::endl;
119   ierr = VecDestroy(&vec);CHKERRQ(ierr);
120   std::cout << "Destroyed VecMoab." << std::endl;
121   ierr = DMDestroy(&user.dm);CHKERRQ(ierr);
122   std::cout << "Destroyed DMMoab." << std::endl;
123   ierr = PetscFinalize();
124   return ierr;
125 }
126 
127 /*TEST
128 
129      build:
130        requires: moab
131 
132      test:
133 
134 TEST*/
135