program test_grid

   use bmad

      type (lat_struct) lat
      type (ele_struct) ele 
      type (coord_struct), allocatable:: co(:)
      type(track_struct) track
      integer ix, i, j,k
      integer nargs,iargc
      integer lun
      character*140 lat_file
      character*120 line
      logical err/.false./

      nargs = command_argument_count()
      if(nargs == 1)then
         call get_command_argument(1,lat_file)
         print *, 'Using ', trim(lat_file)
       else
      lat_file = 'bmad.'
      print '(a37,$)',' Lattice file name ? (default= bmad.) '
      read(5,'(a)') line
       call string_trim(line, line, ix)
       lat_file = line
       if(ix == 0) lat_file = 'bmad.'
       print *, ' lat_file = ', lat_file
      endif

       call bmad_parser (lat_file, lat)
       call reallocate_coord(co,lat%n_ele_max)
       lun=lunget()
       print *,' lun = ', lun
       co(0)%vec=0.
       do i=1,lat%n_ele_track
        track%n_pt = -1
        call track1(co(i-1),lat%ele(i),lat%param,co(i), track=track)
          print *,' track%n_pt = ', track%n_pt
           do k=1,track%n_pt
            write(lun,'(a,6es12.4,1x,2es12.4)')'track_orb',track%orb(k)%vec, track%orb(k)%s,track%orb(k)%t
            print '(a,6es12.4,2es12.4)','track_orb',track%orb(k)%vec, track%orb(k)%s,track%orb(k)%t
           end do

        print '(i10,1x,6es12.4,1x,es12.4)',i,co(i)%vec, lat%ele(i)%s
       end do
close(unit=lun)
end