百度地图开发之计算两点之间的距离
pk = 180 / 3.14169 a1 = lat_a / pk a2 = lng_a / pk b1 = lat_b / pk b2 = lng_b / pk t1 = math.cos(a1) * math.cos(a2) * math.cos(b1) * math.cos(b2) t2 = math.cos(a1) * math.sin(a2) * math.cos(b1) * math.sin(b2) t3 = math.sin(a1) * math.sin(b1) tt = math.acos(t1 + t2 + t3) return 6366000 * tt
