The root process of rank equal to 0 instantiates a variable, variable_to_share, which is equal to 100. This variable will be shared with the other processes of the communication group:

if rank == 0: 
   variable_to_share = 100  

To perform this, we also introduce the broadcast communication statement:

variable_to_share = comm.bcast(variable_to_share, root=0) 

Here, the parameters in the function are as follows:

• The data to be shared (variable_to_share).
• The root process, that is, the process of rank equal to 0 (root=0).

Running the code, we have a communication group of 10 processes, and variable_to_share is shared between the other processes in the group. Finally, the print statement visualizes the rank of the running process and the value of its variable:

print("process = %d" %rank + " variable shared  = %d "    
                     %variable_to_share) 

After setting 10 processes, the output obtained is as follows:

C:>mpiexec -n 10 python broadcast.py 
process = 0 
variable shared = 100 
process = 8 
variable shared = 100 
process = 2 variable 
shared = 100 
process = 3 
variable shared = 100 
process = 4 
variable shared = 100 
process = 5 
variable shared = 100 
process = 9 
variable shared = 100 
process = 6 
variable shared = 100 
process = 1 
variable shared = 100 
process = 7 
variable shared = 100