program aveamp
      
      real total, cnt, average, amp
      integer goodline
      
C     If GOODLINE = 0, line was read in fine
C     if GOODLINE > 0, line was read, but didn't match format - problem
C     if GOODLINE < 0, end of file has been reached
      
      total = 0.0
      cnt = 0.0
      
      open(1, 
     +  file='/data2/fortran_class/transfer/lightning.sm.txt',
     +  status='old')
     
      open(10,file='amp.out',status='unknown')
     
      read(1,1000,iostat=goodline) amp
      do while (goodline.eq.0)
         total = total + amp
	 cnt = cnt + 1.0
	 
	 read(1,1000,iostat=goodline) amp
	 
	 print *, goodline, amp
      end do
	 
      average = total / cnt
      write(*,'("Average amp is ",f4.1)') average
      write(10,1010) average
      
 1000 format(34x,f8.1)
 1010 format("Average amp is ",f14.1)
     
      stop
      end