3       radian = 180/3.14159265
5       az1 = expr()/radian
10      el1 = expr()/radian
20      az2 = expr()/radian
30      el2 = expr()/radian
40      alpha = az1-az2
50      cosa = sin(el1)*sin(el2) + cos(el1)*cos(el2)*cos(alpha)
60      dist = atn((1-cosa^2)^.5 / cosa) * radian * 3600
70      sinb = cos(el1) * sin(alpha)
80      cosb = sin(el1)*cos(el2) - cos(el1)*sin(el2)*cos(alpha)
81      angle = atn(sinb / cosb ) * radian
82      if(cosb > 0) angle = angle + 180
84      angle = angle + 360
86      if(angle > 360) angle = angle - 360
100      angle = int(angle+.5)
110      print dist "   " angle
120      goto 3
run
