Linux and UNIX Man Pages

Linux & Unix Commands - Search Man Pages

mpi_comm_rank(3openmpi) [osx man page]

MPI_Comm_rank(3OpenMPI) 												   MPI_Comm_rank(3OpenMPI)

NAME
MPI_Comm_rank - Determines the rank of the calling process in the communicator. SYNTAX
C Syntax #include <mpi.h> int MPI_Comm_rank(MPI_Comm comm, int *rank) Fortran Syntax INCLUDE 'mpif.h' MPI_COMM_RANK(COMM, RANK, IERROR) INTEGER COMM, RANK, IERROR C++ Syntax #include <mpi.h> int Comm::Get_rank() const INPUT PARAMETERS
comm Communicator (handle). OUTPUT PARAMETERS
rank Rank of the calling process in group of comm (integer). IERROR Fortran only: Error status (integer). DESCRIPTION
This function gives the rank of the process in the particular communicator's group. It is equivalent to accessing the communicator's group with MPI_Comm_group, computing the rank using MPI_Group_rank, and then freeing the temporary group via MPI_Group_free. Many programs will be written with the master-slave model, where one process (such as the rank-zero process) will play a supervisory role, and the other processes will serve as compute nodes. In this framework, MPI_Comm_size and MPI_Comm_rank are useful for determining the roles of the various processes of a communicator. ERRORS
Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument. C++ func- tions do not return errors. If the default error handler is set to MPI::ERRORS_THROW_EXCEPTIONS, then on error the C++ exception mechanism will be used to throw an MPI:Exception object. Before the error value is returned, the current MPI error handler is called. By default, this error handler aborts the MPI job, except for I/O function errors. The error handler may be changed with MPI_Comm_set_errhandler; the predefined error handler MPI_ERRORS_RETURN may be used to cause error values to be returned. Note that MPI does not guarantee that an MPI program can continue past an error. SEE ALSO
MPI_Comm_group MPI_Comm_size MPI_Comm_compare Open MPI 1.2 September 2006 MPI_Comm_rank(3OpenMPI)

Check Out this Related Man Page

MPI_Graph_neighbors_count(3OpenMPI)									       MPI_Graph_neighbors_count(3OpenMPI)

NAME
MPI_Graph_neighbors_count - Returns the number of neighbors of a node associated with a graph topology. SYNTAX
C Syntax #include <mpi.h> int MPI_Graph_neighbors_count(MPI_Comm comm, int rank, int *nneighbors) Fortran Syntax INCLUDE 'mpif.h' MPI_GRAPH_NEIGHBORS_COUNT(COMM, RANK, NNEIGHBORS, IERROR) INTEGER COMM, RANK, NNEIGHBORS, IERROR C++ Syntax #include <mpi.h> int Graphcomm::Get_neighbors_count(int rank) const INPUT PARAMETERS
comm Communicator with graph topology (handle). rank Rank of process in group of comm (integer). OUTPUT PARAMETERS
nneighbors Number of neighbors of specified process (integer). IERROR Fortran only: Error status (integer). DESCRIPTION
MPI_Graph_neighbors_count and MPI_Graph_neighbors provide adjacency information for a general, graph topology. MPI_Graph_neighbors_count returns the number of neighbors for the process signified by rank. ERRORS
Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument. C++ func- tions do not return errors. If the default error handler is set to MPI::ERRORS_THROW_EXCEPTIONS, then on error the C++ exception mechanism will be used to throw an MPI:Exception object. Before the error value is returned, the current MPI error handler is called. By default, this error handler aborts the MPI job, except for I/O function errors. The error handler may be changed with MPI_Comm_set_errhandler; the predefined error handler MPI_ERRORS_RETURN may be used to cause error values to be returned. Note that MPI does not guarantee that an MPI program can continue past an error. SEE ALSO
MPI_Graph_neighbors Open MPI 1.2 September 2006 MPI_Graph_neighbors_count(3OpenMPI)
Man Page