R语言使用ggplot2可视化互相覆盖的直方图实战（Overlaying histograms）

dat <- data.frame(xx = c(runif(100,20,50),runif(100,40,80),runif(100,0,30)),yy = rep(letters[1:3],each = 100))ggplot(dat,aes(x=xx)) + geom_histogram(data=subset(dat,yy == 'a'),fill = "red", alpha = 0.2) +geom_histogram(data=subset(dat,yy == 'b'),fill = "blue", alpha = 0.2) +geom_histogram(data=subset(dat,yy == 'c'),fill = "green", alpha = 0.2)

参考：R

参考：Overlaying histograms with ggplot2 in R