populate the array using the start/end indices
subroutine update_array() !! populate the array using the start/end indices integer :: i array = 0 do i = 1, n_lines array(istart_array(i,1):iend_array(i,1),& istart_array(i,2):iend_array(i,2),& istart_array(i,3):iend_array(i,3)) = i end do end subroutine update_array