r - R:图例()错误

Question

我正在尝试为图生成图例，以显示颜色与图中群集＃的关系。我实际上只需要生成图例，然后将其复制并粘贴到PowerPoint幻灯片中就不需要它了。

我在这里找到了我想要的代码:

http://www.statmethods.net/advgraphs/axes.html

# Legend Example
attach(mtcars)
boxplot(mpg~cyl, main="Milage by Car Weight",
    yaxt="n", xlab="Milage", horizontal=TRUE,
   col=terrain.colors(3))
legend("topright", inset=.05, title="Number of Cylinders",
    c("4","6","8"), fill=terrain.colors(3), horiz=TRUE)

但很难复制它。这是我的代码:

plot(seq(1,7), seq(1,7), col = c(1:7))
legend("topright", inset = .05, title = "Cluster Colors"
    ,fill = c(1:7), horiz=T)

当我运行它时，出现以下错误:

Error in as.graphicsAnnot(legend) : 
  argument "legend" is missing, with no default

有什么建议？

Answer 1

原始图有一个参数“传奇”，它只是未命名的参数。如此处更新:

legend("topright", inset=.05, title="Number of Cylinders",
   legend =c("4","6","8"), fill=terrain.colors(3), horiz=TRUE)

所以，您需要的是这个。

plot(seq(1,7), seq(1,7), col = c(1:7))
legend("topright", inset = .05, title = "Cluster Colors",legend= c(1:7)
       ,fill = c(1:7), horiz=TRUE)

像?中一样，?legend命令对于了解这些情况很有用。