C+
C NAME:
C	smei_skyd_addvalue
C PURPOSE:
C	Make sure that the values added together
C	are all about the same size
C	(i.e. do not add 0.5 and 359.5 but 0.5 and -0.5 for angles).
C CALLING SEQUENCE:
	subroutine smei_skyd_addvalue(val,dval,hit,sum)
C INPUTS:
C	val		real
C	dval		real
C	hit		real		number of hits in bin so far
C	sum		real		accumulated value
C OUTPUTS:
C	sum		real		update accumulated value
C MODIFICATION HISTORY:
C	NOV-2005, Paul Hick (UCSD/CASS; pphick@ucsd.edu)
C-
	    real	val
	    real	dval
	    real	hit
	    real	sum

	real		x
	real		d

	if (hit .eq. 0.0) then

	    sum = val

	else

	    x = val
	    d = x-sum/hit
	    if (abs(d) .gt. 0.5*dval) x = x-sign(dval,d)

	    sum = sum+x

	end if

	return
	end