如何在下图中添加关键图例
我想在右上角的某个地方有一个关键的传说,有两个短的水平彩条,红色的应该说“整形手术出错了”,蓝色应该说“德国”。
我使用以下代码生成图:
bar2 <- read.table("div/ana-mut[...]/barriers-set-2.dat", sep=" ")
bar2val <- c(bar2$V1, bar2$V2)
bar3 <- read.table("div/ana-mut[...]/barriers-set-3.dat", sep=" ")
bar3val <- c(bar3$V1, bar3$V2)
p1 <- hist(subset(bar2val, bar2val < 30), breaks=30)
p2 <- hist(subset(bar3val, bar3val < 30), breaks=30)
plot(p1, col=rgb(1,0,0,8/9), main="Barrier distribution", xlab="Barrier [kcal/mol]", ylab="Mutant count")
plot(p2, col=rgb(0,0,1,8/9), add=T)
任何提示都将不胜感激。
答案 0 :(得分:17)
图例命令可以解决这个问题:
legend("topright", c("Germany", "Plastic"), col=c("blue", "red"), lwd=10)
要获得两个短的水平颜色条,只需使用标准线,但增加线条粗细。正如Roland指出的那样,您也可以使用fill
参数:
legend("topright", c("Germany", "Plastic"), fill=c("blue", "red"))
有关详细信息,请参阅?legend
。
答案 1 :(得分:2)
这是另一种解决方案(请参阅下面的代码)
# some semi-random data …
df <- structure(list(Germany = c(1L, 3L, 6L, 1L, 2L), Plastic = c(2L,
5L, 4L, 2L, 3L)), .Names = c("Germany", "Plastic"), class = "data.frame", row.names = c(NA,
-5L))
# Expand right side of clipping rect to make room for the legend
par(xpd=T, mar=par()$mar+c(0,0,0,4))
# Graph data (transposing the matrix) using heat colors,
# put 10% of the space between each bar, and make labels
# smaller with horizontal y-axis labels
barplot(t(df), main="Barrier distribution", xlab="Barrier [kcal/mol]", ylab="Mutant count",
col=c("blue", "red"), space=0.1, cex.axis=0.8, las=1,
names.arg=c("Mon","Tue","Wed","Thu","Fri"), cex=0.8)
# Place the legend at (4,9) using blue and red
legend(4, 9, names(df), lwd=4, col=c("blue", "red"))
# Restore default clipping rect
par(mar=c(5, 4, 4, 2) + 0.1)