if ( my_id == master )

        numsent = 0
c
c  BROADCAST X to all the workers.
c
        call MPI_BCAST ( x, cols, MPI_DOUBLE_PRECISION, master, 
     &    MPI_COMM_WORLD, ierr )

c
c  SEND row I to worker process I; tag the message with the row number.
c
        do i = 1, min ( num_procs-1, rows )

          do j = 1, cols
            buffer(j) = a(i,j)
          end do

          call MPI_SEND ( buffer, cols, MPI_DOUBLE_PRECISION, i, 
     &      i, MPI_COMM_WORLD, ierr )

          numsent = numsent + 1

        end do