MPI Lab Problem

Code scope

• Let all of your codes between MPI_Init(), MPI_Finalize()

• Codes out of the MPI_Init(), MPI_Finalize() may not executed by all processes

Argument

• argc means the number of argument

• argv store the argument

• argv include the executable file

Collective call

• Bcast                                                           

• Reduce

• Allreduce

• Scatter

• Gather

• Alltoall

• Allgather

Hint

• Calculate the start position, workload by rank

• Be care of the type

• Calculate the local area

• use MPI_Reduce to collect all local area