program READ_CWN

c  Glen Cowan
c  12 December, 1999
c  Test program for reading column wise ntuples.

       implicit        NONE

c  Constants

       integer           max_col
       parameter         (max_col = 9)

c  Needed for HBOOK routines

       integer           hsize
       parameter         (hsize = 1000000)
       integer           hmemor (hsize)
       common  /pawc/    hmemor

c  Common block for ntuple

       real              p1, p2, p3
       common  /evtblk/  p1(3), p2(3), p3(3)

c  Local variables

       character*80      infile
       character*3       tag(max_col)
       character*80      title

       integer           i
       integer           icycle
       integer           id
       integer           j
       integer           k
       integer           ierr
       integer           istat
       integer           lrec               / 0 /
       integer           lw
       integer           num_events
       integer           nvar

       real              rlow(max_col) 
       real              rhigh(max_col)

c  Initialize HBOOK, open input file

       call HLIMIT (hsize)
       write (*, *) 'input file:'
       read (*, fmt='(a80)') infile
       call HROPEN (20, 'ntuple', infile, ' ', 1024, istat)
       call HRIN (0, 999999, 0)              ! read highest cycle

c  Get information on ntuple

       id = 1
       call READ_CWN_SETUP                       ! created by test_cwn
       call HGIVEN (id, title, nvar, tag, rlow, rhigh)
       write (*, *) 'title = ', title
       write (*, *) 'nvar = ', nvar
       write (*, *)

c  Loop over events and print event info to screen
       
       call HNOENT (id, num_events)
       write (*, *) 'num_events = ', num_events
       do i = 1, num_events
         call HGNT (id, i, ierr)         ! reads in variables via evtblk
         write (*, *)  'event = ', i
         write (*, *) 'p1 = ', p1(1), p1(2), p1(3)
         write (*, *) 'p2 = ', p2(1), p2(2), p2(3)
         write (*, *) 'p3 = ', p3(1), p3(2), p3(3)
       end do

       call HREND ('ntuple')

       stop
       END