8. 判断点是否在凸多边形内 9. 寻找点集的graham算法 10.寻找点集凸包的卷包裹法 11.判断线段是否在多边形内 12.求简单多边形的重心 13.求凸多边形的重心14.求肯定在给定多边形内的一个点15.求从多边形外一点出发到该多边形的切线16.判断多边形的核是否存在-8. In judging whether a convex polygon 9. Find points of graham algorithm 10. Find point set of convex hull volume parcels Act 11. Line judge whether the polygon 12. Seeking simple polygon focus 13. Convex Polygon focus 14. For sure in a given polygon within the a point 15. demand from outside the polygon to the starting point of the polygon Tangent 16. the nuclear polygon judgment whether there