	FUNCTION IREVRS(I)
C	ROUTINE TO GIVE THE OPPOSING CUBE DIRECTION FROM I
	IF(I.EQ.1) J=3
	IF(I.EQ.2) J=4
	IF(I.EQ.3) J=1
	IF(I.EQ.4) J=2
	IF(I.EQ.5) J=6
	IF(I.EQ.6) J=5
	IREVRS=J
	RETURN
	END
