program READ_RWN

c  Glen Cowan
c  16 October, 1999
c  Test program for reading row wise ntuples.

       implicit        NONE

c  Constants

       integer           max_col
       parameter         (max_col = 9)

c  Needed for HBOOK routines

       integer           hsize
       parameter         (hsize = 500000)
       integer           hmemor (hsize)
       common  /pawc/    hmemor

c  Local variables

       character*60      chrout            / 'read_rwn' /
       character*80      infile
       character*3       tag(max_col)
       character*80      title

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

       real              event(max_col)
       real              rlow(max_col) 
       real              rhigh(max_col)

c  Initialize HBOOK, open input file, book ntuple.

       call HLIMIT (hsize)
       infile = 'test_rwn.hbook'
       call HROPEN (20, 'ntuple', infile, ' ', 1024, istat)
       call HRIN (0, 9999, 0)

c  Get information on ntuple number 1

       call HGIVEN (1, title, nvar, tag, rlow, rhigh)
       write (*, *) 'title = ', title
       do i = 1, nvar
         write (*, *) 'i, rlo, rhi = ', i, rlow(i), rhigh(i)
         write (*, *) 'tag = ', tag(i)
       end do
       write (*, *)

c  Loop over events and print event info to screen
       
       call HNOENT (1, num_events)
       write (*, *) 'num_events = ', num_events
       call HGNPAR (1, chrout)
       do i = 1, num_events
         call HGNF (1, i, event, ierr)
         write (*, *)  'event = ', i
         do j = 1, 9
           write (*, *) j, event(j)
         end do
       end do

       call HREND ('ntuple')

       stop
       END