Manpages - MPI_Topo_test.3

MPI_Topo_test - Determines the type of topology (if any) associated with a communicator.

  #include <mpi.h>
  int MPI_Topo_test(MPI_Comm comm, int *top_type)

  USE MPI
  ! or the older form: INCLUDE 'mpif.h'
  MPI_TOPO_TEST(COMM, TOP_TYPE, IERROR)
  	INTEGER	COMM, TOP_TYPE, IERROR

  USE mpi_f08
  MPI_Topo_test(comm, status, ierror)
  	TYPE(MPI_Comm), INTENT(IN) :: comm
  	INTEGER, INTENT(OUT) :: status
  	INTEGER, OPTIONAL, INTENT(OUT) :: ierror
  		DOUBLE PRECISION MPI_Wtick()
  		DOUBLE PRECISION MPI_Wtime()

  #include <mpi.h>
  int Comm::Get_topology() const

comm

Communicator (handle).

top_type

Topology type of communicator comm (choice).

IERROR

Fortran only: Error status (integer).

The function MPI_Topo_test returns the type of topology that is assigned to a communicator.

The output value top_type is one of the following:

      MPI_GRAPH		graph topology
      MPI_CART		Cartesian topology
      MPI_DIST_GRAPH	distributed graph topology
      MPI_UNDEFINED	no topology

Almost all MPI routines return an error value; C routines as the value of the function and Fortran routines in the last argument. C++ functions 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.

MPI_Graph_create
MPI_Cart_create