MPI_Bcast

Broadcasts a message from the process with rank "root" to all other processes of the communicator

Syntax

• A = MPI_Bcast(A, Root)
• A = MPI_Bcast(A, Root, Comm)

Input argument

• A - a nelson variable.
• Root - a integer value: rank of broadcast root.
• Comm - a MPI_Comm object.

Output argument

• A - broadcasted array.

Description

This function is used to broadcast an array to all group members.

See also

MPI_Barrier.

Example

mpiexec([modulepath('mpi'), '/examples/help_examples/MPI_Bcast.m'], 4)

if ~MPI_Initialized()
  MPI_Init();
end
my_rank = MPI_Comm_rank();
num_ranks = MPI_Comm_size();
root = 0;
if (my_rank == 0)
  buff = 777;
else
  buff = 0;
end
disp(['rank: ', int2str(my_rank), ': before Bcast, buff is ', int2str(buff)])
buff = MPI_Bcast(buff, root);
disp(['rank: ', int2str(my_rank), ': after Bcast, buff is ', int2str(buff)])
if MPI_Initialized()
  MPI_Finalize();
end

History

Author

Allan CORNET