在写SSI算法的时候，因为要画稳定图，所以牵涉到了双坐标轴的使用问题。查看Matlab的Help文件，对双坐标轴函数（plotyy）的表述不是很详细，或者是我没有读太懂吧。

下面对plotyy函数的使用做一个详细的学习,SSI algorithm in the time to write because of the need to draw a stable map, so involved the use of dual-axis problem. See Matlab s Help files, on the dual-axis function (plotyy) expression is not very detailed, I did not read or understand it too. Plotyy function following the use of a detailed study