real apcor(20,4), weight(20,4)

	do i=1,20
	 do ichip=1,4
	   apcor(i,ichip) = 0.
	   weight(i,ichip) = 0.
	 end do
	end do
	open(1,file='ic1613_u56750.phot.apcor',status='old')

1	read(1,*,end=99) image, ichip, x, y, amag, ap, err, w
	if (image .lt. 20 .and. ichip .lt. 4) then
	apcor(image+1,ichip+1) = apcor(image+1,ichip+1) + w*ap
	weight(image+1,ichip+1) = weight(image+1,ichip+1) + w
	end if
	goto 1

99	continue
	do image=1,10
	 do ichip=1,4
	   print *, apcor(image,ichip), weight(image,ichip),
     &      apcor(image,ichip)/weight(image,ichip)
	 end do
	end do

	stop
	end