12 DO 10 ipair = 1,npairs
14 IF (body(n+ipair).GT.0.0d0)
THEN
17 ebin = ebin + body(2*ipair-1)*body(2*ipair)*ht/
28 IF (i.LE.2*npairs)
THEN
36 IF (body(j).EQ.0.0d0) go to 30
40 potj = potj + body(j)/sqrt(a1*a1 + a2*a2 + a3*a3)
43 pot = pot + body(i)*potj
49 zkin = zkin + body(i)*(xdot(1,i)**2 + xdot(2,i)**2 +
69 etide = etide - body(i)*mp/sqrt(ri2)