R中的灰度堆积区域图

Question

我正在使用plotrix包中的stackpoly()命令在R中绘制堆积区域图。至少可以说，默认颜色很明显。有没有办法使用符号或灰度代码？

Answer 1

来自?stackpoly：

 col: Color to fill the polygons. If NULL, ‘rainbow’ will be called
      to generate the colors. If NA, the polygons will not be
      filled.

稍微修改?stackpoly中的示例：

stackpoly(matrix(cumsum(testx),nrow=10),main="Test Stackpoly I",
   xaxlab=c("One","Two","Three","Four","Five","Six","Seven","Eight","Nine","Ten"),
  border="black",staxx=TRUE,
col=gray(seq(0.1,0.9,length=10)))