Mesh Oriented datABase  (version 5.5.1)
An array-based unstructured mesh library
ReadPartFile.cpp
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1 /** @example ReadPartFile.cpp
2  *
3  * read partition file created by a Zoltan process, that used the global ids for
4  * identification of entities
5  */
6 
7 #include "moab/Core.hpp"
8 #include <iostream>
9 #include <fstream>
10 
11 using namespace moab;
12 using namespace std;
13 
14 #ifndef MESH_DIR
15 #define MESH_DIR "."
16 #endif
17 
18 // Note: change the file name below to test a trivial "No such file or directory" error
19 string test_file_name = string( MESH_DIR ) + string( "/3k-tri-sphere.vtk" );
21 int nparts;
22 int main( int argc, char** argv )
23 {
24  // Get MOAB instance
25  Interface* mb = new( std::nothrow ) Core;
26  if( NULL == mb ) return 1;
27 
28  // Need option handling here for input filename
29  if( argc > 4 )
30  {
31  // User has input a mesh file
32  test_file_name = argv[1];
33  part_file_name = argv[2];
34  nparts = atoi( argv[3] );
35  }
36  else
37  {
38  cerr << " usage is " << argv[0] << " <input file> <part file> <#parts> <output file> \n";
39  exit( 0 );
40  }
41  ifstream inFile;
42  inFile.open( part_file_name.c_str() );
43  if( !inFile )
44  {
45  cerr << "Unable to open file " << part_file_name << "\n";
46  exit( 1 ); // call system to stop
47  }
48  // Load the mesh from file
49  ErrorCode rval = mb->load_mesh( test_file_name.c_str() );MB_CHK_ERR( rval );
50 
51  // Get sets entities, by type
52  Range sets;
53  rval = mb->get_entities_by_type( 0, MBENTITYSET, sets );MB_CHK_ERR( rval );
54 
55  // Output the number of sets
56  cout << "Number of sets is " << sets.size() << endl;
57  // remove the sets that have a PARALLEL_PARTITION tag
58 
59  Tag tag;
60  rval = mb->tag_get_handle( "PARALLEL_PARTITION", tag );MB_CHK_ERR( rval );
61 
62  int i = 0;
63  int num_deleted_sets = 0;
64  for( Range::iterator it = sets.begin(); it != sets.end(); it++, i++ )
65  {
66  EntityHandle eh = *it;
67  // cout << " set :" << mb->id_from_handle(eh) <<"\n";
68  int val = -1;
69  rval = mb->tag_get_data( tag, &eh, 1, &val );
70  if( val != -1 )
71  {
72  num_deleted_sets++;
73  rval = mb->delete_entities( &eh, 1 ); // delete the set, we will have a new partition soon
74  }
75  }
76  if( num_deleted_sets ) cout << "delete " << num_deleted_sets << " existing partition sets, and create new ones \n";
77  Range cells; // get them by dimension 2!
78  rval = mb->get_entities_by_dimension( 0, 2, cells );MB_CHK_ERR( rval );
79  EntityHandle* psets = new EntityHandle[nparts];
80  for( int i = 0; i < nparts; i++ )
81  {
82  rval = mb->create_meshset( MESHSET_SET, psets[i] );MB_CHK_ERR( rval );
83  rval = mb->tag_set_data( tag, &( psets[i] ), 1, &i );MB_CHK_ERR( rval );
84  }
85 
86  for( Range::iterator it = cells.begin(); it != cells.end(); it++ )
87  {
88  int part;
89  EntityHandle eh = *it;
90  inFile >> part;
91  rval = mb->add_entities( psets[part], &eh, 1 );MB_CHK_ERR( rval );
92  }
93  mb->write_file( argv[4] );
94 
95  delete mb;
96 
97  return 0;
98 }