r - 在直方图中添加曲线？

Question

我想添加一条曲线，它的 x 和 y 坐标已经定义到直方图。考虑下面的直方图：

set.seed(38593)
expRandom <- rexp(10000)
x <- seq(from = 0.05, to = 10, by = 0.001)
y <- exp(-x)
### Now I'd like to first draw my histogram and then 
### add my plot(x,y) to my existing histogram:
hist(expRandom, freq = FALSE)

### ?? How to add my plot(x,y) to my histogram above?

谢谢，

Answer 1

设置在直方图freq = FALSE中绘制密度而不是频率，并使用points（或lines）添加数据。

hist(expRandom, freq = FALSE)
points(x,y)

您还可以避免 y通过使用curve添加曲线来预先计算值

hist(expRandom, freq = FALSE)
curve(dexp, from = 0, to  = 10, add = TRUE)