Pi Example continued

• { if (myid == 0)

• { printf (“Enter the number of intervals: (0 quits) “);

• scanf (“%d”, &n);

• }

• MPI_Bcast (&n, 1, MPI_INT, 0, MPI_COMMWORLD);

• if (n == 0) break;

• h = 1.0 / (double) n;

• sum = 0.0;

• for (i = myid+1; i <= n; i += numprocs)

• { x = h * ((double) i - 0.5); sum += 4.0 / 1.0 + x*x): }

• mypi = h * sum;

• MPI_Reduce (&mypi, &pi,1, MPI_DOUBLE,MPI_SUM, 0,MPI_COMMWORLD);

• if (myid == 0)

• printf(“pi is approximately %.16f, Error is %.16f\n”,pi, fabs(pi-PI35DT); }

• MPI_Finalize; }

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