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Hands-on: Collective operations

In this exercise we test different routines for collective communication.
© CSC - IT Center for Science Ltd.
In this exercise we test different routines for collective communication.
Source code for this exercise is located in mpi/collectives/
First, write a program where rank 0 sends an array containing numbers from 0
to 7 to all the other ranks using collective communication.
Next, we continue with four MPI tasks with following initial data vectors:
Task 0:01234567
Task 1:89101112131415
Task 2:1617181920212223
Task 3:2425262728293031
In addition, each task has a receive buffer for eight elements and the values
in the buffer are initialized to -1. Implement a program that sends and
receives values from the data vectors to receive buffers using a single
collective communication routine for each case, so that the receive buffers
will have the following values. You can start from the skeleton file

Case 1

Task 0:01-1-1-1-1-1-1
Task 1:23-1-1-1-1-1-1
Task 2:45-1-1-1-1-1-1
Task 3:67-1-1-1-1-1-1

Case 2

Task 0:-1-1-1-1-1-1-1-1
Task 1:018916172425
Task 2:-1-1-1-1-1-1-1-1
Task 3:-1-1-1-1-1-1-1-1

Case 3

Task 0:810121416182022
Task 1:-1-1-1-1-1-1-1-1
Task 2:4042444648505254
Task 3:-1-1-1-1-1-1-1-1
Tip: create two communicators
© CSC - IT Center for Science Ltd.
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Python in High Performance Computing

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