r - 图例不显示颜色

Question

我在R.

plot(NA,xlim=c(0,1),ylim=c(0,1), xlab=expression(delta),ylab="K", xaxs="i",yaxs="i",main = "Zones of extreme equality and inequality in BO1") # Empty plot
cols <- c("red","black")
legend("topright",legend=c("Gini < 0.05","Gini > 0.6"), density=c(NA,NA), angle=c(NA,NA), col=cols)

图例中的框没有上色。这里有什么问题？

Answer 1

尝试使用pch：

legend("topright",
       legend=c("Gini < 0.05","Gini > 0.6"), 
       pch=15,
       col=cols)

Answer 2

您也可以只填充颜色：

legend("topright",legend=c("Gini < 0.05","Gini > 0.6"), fill=cols)

Answer 3

也许你可以这样尝试：

legend("topright",legend=c("Gini < 0.05","Gini > 0.6"), pch=15, col=cols)