Let's now see an example in which we've used the broadcast function. We have a root process of rank equal to 0 that shares its own data, variable_to_share, with the other processes defined in the communicator group:

1. Let's import the mpi4py library:

from mpi4py import MPI 

2. Now, let's define the communicator and the rank parameter:

comm = MPI.COMM_WORLD 
rank = comm.Get_rank() 

3. As far as the process of rank equal to 0 is concerned, we define the variable to be shared among the other processes:

if rank == 0: 
    variable_to_share = 100      
else: 
    variable_to_share = None 

4. Finally, we define a broadcast, having the rank process equal to zero as its root:

variable_to_share = comm.bcast(variable_to_share, root=0) 
print("process = %d" %rank + " variable shared  = %d "    
                               %variable_to_share)