XY坐标图。非常漂亮的XY坐标图，可以显示多条数据曲线，工控必备-XY coordinate diagram. Very beautiful XY plot, you can display multiple data curves, Industrial necessary

xygraph源代码，早期版本啊，采用pas语言编写啊，但是思想还是比较清晰的(Xygraph source code, the earlier version, ah, using PAS language, ah, but the idea is still relatively clear)