character file*24
	real tot(0:10,0:3), norm(0:10,0:3)	

	print '(1x,''Enter file name: ''$)'
	read '(a)', file
	l = index(file,' ') - 1

	open(1,file=file(1:l)//'.phot.apcor',status='old')

1	read(1,*,end=99) iframe, ichip, x, y, v, ap, error, weight

	tot(iframe,ichip) = tot(iframe,ichip) + ap*weight
	norm(iframe,ichip) = norm(iframe,ichip) + weight

	goto 1
99	continue

	do iframe=0,1
	  do ichip=0,3
	    print *, iframe, ichip, tot(iframe,ichip)/norm(iframe,ichip)
	  end do
	end do

	stop
	end