spidernet

代码说明：

  此程序段能完整画出所要图形曲线的蛛网图，其它网站上基本没有提供，对学习经济控制问题是个很有帮助的的功能程序。(This program segment to be able to draw a complete graph of the cobweb diagram, other sites basically did not provide for the study of economic control issue is a useful feature programs.)