Finding PI using MPI collective operations

$username@machine [~/workshop] % mpxlf -O -o pi pi.f
$username@machine [~/workshop] % poe pi -rmpool 1 -procs 4
Process 2 of 4 is alive
Process 3 of 4 is alive
Process 1 of 4 is alive
Process 0 of 4 is alive
Enter the number of intervals: (0 quits)
100
pi is approximately: 3.1416009869231249 Error is: .0000083333333318
Enter the number of intervals: (0 quits)
100000
pi is approximately: 3.1415926535981167 Error is: .0000000000083236
Enter the number of intervals: (0 quits)
0
username@machine [~/workshop] %