第一个pmin是返回小于100的元素，pmax是返回大于0的元素的意思吧，但是dat_simscore还没声明怎么能用它去声明它自己的呢，我这运行不了
dat_simscore<−pmin(dat_simscore, 100)
dat_simscore<−pmax(0, dat_simscore)
提示这样的错误
> dat_simscore <-pmin(dat_simscore, 100)
Error in pmin(dat_simscore, 100) : object 'dat_simscore' not found

晕，要点“复制代码”，用鼠标选会出错的

## generate sim data
set.seed(123)
dat_sim <- data.frame(id = 1:1000,
                      score = rnorm(1000, 60, 20))

dat_sim$score <- pmin(dat_sim$score, 100)
dat_sim$score <- pmax(0, dat_sim$score)

## split and plot

red <- dat_sim$score[dat_sim$score < 60]
blue <- dat_sim$score[dat_sim$score >= 60 & dat_sim$score < 80]
green <- dat_sim$score[dat_sim$score >= 80]

draw_hist <- function(draw_data, col_name) {
    hist(draw_data, col = col_name, xlim = c(20,100), ylim = c(0,200),
         breaks = c(10*2:10),
         xlab = "Name", ylab = "Score", main = "Score")
}


draw_hist(red, "red")
par(new=T)  
draw_hist(blue, "blue")
par(new=T)
draw_hist(green, "green")

我发誓我是点复制代码复制出来的，然后就变成那样奇奇怪怪的

搞懂了，非常非常感谢耐心的回答