library(ggplot2)
dev.new()
set.seed(1684)
x = seq(15, 33, by = 0.9)
f <- function(x) {
  out <- ifelse(
    x < 15 | 33 < x,
    0,
    ifelse(
      15 <= x & x <= 24,
      (2*(x-15))/((33-15)*(24-15)),
      ifelse(
        24 < x & x <= 33,
        (2*(33-x))/((33-15)*(33-24)),
        NA_real_
      )))
  if (any((is.na(out) | is.nan(out)) & (!is.na(x) & !is.nan(x)))) {
    warning("f(x) undefined for some input values")
  }
  out
}

x_accept <- numeric(0)
while (length(x_accept) != 105) {
  x1 = runif(1, min = 15, max = 33)
  num = runif(1, min = 0, max = 1)
  if (num < (f(x1)/2/(33-15))) {
    x_accept = c(x_accept, x1)
  }
}

histo <- data.frame(x = x_accept)
dat <- data.frame(x = x, y = f(x), z = histo)
ggplot(dat)  
  geom_line(aes(x, y), color = "red")  
  geom_histogram(aes(histo), alpha = .5, binwidth = 1)

When I use this code it gives me the error, I think it assumes that 'histo' is a list, but it's a dataframe, so I don't really know what's wrong.

CodePudding user response：

use data=histo and set x=x and y to density (y=..density..)

ggplot(dat)  
  geom_line(aes(x, y), color = "red")  
  geom_histogram(aes(x,..density..),data=histo, alpha = .5, binwidth = 1)

or using only one dataframe:

dat <- data.frame(x = x, y = f(x), z = x_accept) #z=x_accept instead of histo
ggplot(dat)  
  geom_line(aes(x, y), color = "red")  
  geom_histogram(aes(z,..density..), alpha = .5, binwidth = 1)