libMesh
Functions
splitter.C File Reference

Go to the source code of this file.

Functions

std::string remove_extension (const std::string &filename)
 
int main (int argc, char **argv)
 

Function Documentation

◆ main()

int main ( int  argc,
char **  argv 
)

Definition at line 41 of file splitter.C.

42 {
43  LibMeshInit init (argc, argv);
44 
45  if (libMesh::on_command_line("--help") || argc < 3)
46  {
47  libMesh::out << "Example: " << argv[0] << " --mesh=filename.e --n-procs='4 8 16' "
48  "[--num-ghost-layers <n>] [--dry-run] [--ascii]\n\n"
49  << "--mesh Full name of the mesh file to read in. \n"
50  << "--n-procs Vector of number of processors.\n"
51  << "--num-ghost-layers Number of layers to ghost when partitioning (Default: 1).\n"
52  << "--dry-run Only test the partitioning, don't write any files.\n"
53  << "--ascii Write ASCII cpa files rather than binary cpr files.\n"
54  << std::endl;
55 
56  return 0;
57  }
58 
59  std::string filename = libMesh::command_line_value("--mesh", std::string());
60 
61  std::vector<processor_id_type> all_n_procs;
62  libMesh::command_line_vector("--n-procs", all_n_procs);
63 
64  unsigned int num_ghost_layers = libMesh::command_line_value("--num-ghost-layers", 1);
65 
66  ReplicatedMesh mesh(init.comm());
67 
68  // If the user has requested additional ghosted layers, we need to add a ghosting functor.
69  DefaultCoupling default_coupling;
70  if (num_ghost_layers > 1)
71  {
72  default_coupling.set_n_levels(num_ghost_layers);
73  mesh.add_ghosting_functor(default_coupling);
74  }
75 
76  libMesh::out << "Reading " << filename << std::endl;
77 
78  mesh.read(filename);
79 
80  for (const auto & n_procs : all_n_procs)
81  {
82  libMesh::out << "splitting " << n_procs << " ways..." << std::endl;
83 
84  auto cpr = split_mesh(mesh, n_procs);
85 
86  if (!libMesh::on_command_line("--dry-run"))
87  {
88  libMesh::out << " * writing " << cpr->current_processor_ids().size() << " files per process..." << std::endl;
89 
90  const bool binary = !libMesh::on_command_line("--ascii");
91 
92  cpr->binary() = binary;
93  std::ostringstream outputname;
94  outputname << remove_extension(filename) << (binary ? ".cpr" : ".cpa");
95  cpr->write(outputname.str());
96  }
97  }
98 
99  return 0;
100 }

References libMesh::MeshBase::add_ghosting_functor(), libMesh::command_line_value(), libMesh::command_line_vector(), libMesh::TriangleWrapper::init(), mesh, libMesh::on_command_line(), libMesh::out, libMesh::MeshBase::read(), remove_extension(), libMesh::DefaultCoupling::set_n_levels(), and libMesh::split_mesh().

◆ remove_extension()

std::string remove_extension ( const std::string &  filename)

Definition at line 31 of file splitter.C.

32 {
33  size_t lastdot = filename.find_last_of(".");
34 
35  if (lastdot == std::string::npos)
36  return filename;
37 
38  return filename.substr(0, lastdot);
39 }

Referenced by main().

libMesh::MeshBase::read
virtual void read(const std::string &name, void *mesh_data=nullptr, bool skip_renumber_nodes_and_elements=false, bool skip_find_neighbors=false)=0
Interfaces for reading/writing a mesh to/from a file.
remove_extension
std::string remove_extension(const std::string &filename)
Definition: splitter.C:31
mesh
MeshBase & mesh
Definition: mesh_communication.C:1257
libMesh::ReplicatedMesh
The ReplicatedMesh class is derived from the MeshBase class, and is used to store identical copies of...
Definition: replicated_mesh.h:47
libMesh::TriangleWrapper::init
void init(triangulateio &t)
Initializes the fields of t to nullptr/0 as necessary.
libMesh::command_line_value
T command_line_value(const std::string &, T)
Definition: libmesh.C:931
libMesh::split_mesh
std::unique_ptr< CheckpointIO > split_mesh(MeshBase &mesh, processor_id_type nsplits)
split_mesh takes the given initialized/opened mesh and partitions it into nsplits pieces or chunks.
Definition: checkpoint_io.C:134
libMesh::LibMeshInit
The LibMeshInit class, when constructed, initializes the dependent libraries (e.g.
Definition: libmesh.h:83
libMesh::DefaultCoupling
This class implements the default algebraic coupling in libMesh: elements couple to themselves,...
Definition: default_coupling.h:41
libMesh::MeshBase::add_ghosting_functor
void add_ghosting_functor(GhostingFunctor &ghosting_functor)
Adds a functor which can specify ghosting requirements for use on distributed meshes.
Definition: mesh_base.h:1089
libMesh::command_line_vector
void command_line_vector(const std::string &, std::vector< T > &)
Definition: libmesh.C:976
libMesh::on_command_line
bool on_command_line(std::string arg)
Definition: libmesh.C:898
libMesh::out
OStreamProxy out
libMesh::DefaultCoupling::set_n_levels
void set_n_levels(unsigned int n_levels)
Definition: default_coupling.h:65