R lines() 命令显示交叉线

Question

当我将 lines() 添加到 hist() 时，我得到无法解释的交叉线，你能告诉我为什么吗？请

x <- 
  rgamma(100, shape = 1, rate = 2)

gamma_distr <-
  fitdistr(x, densfun="gamma")

pdf_gamma <- 
  dgamma(x,
         shape = gamma_distr$estimate[1],
         rate = gamma_distr$estimate[2])

hist(x, 100, freq = FALSE)
lines(x = x, y = pdf_gamma, col="red")

Answer 1

试试这个：

library(MASS)

x <- rgamma(100, shape = 1, rate = 2)

gamma_distr <- fitdistr(x, densfun="gamma")

hist(x, 100, freq = FALSE)
curve(dgamma(x,
             shape = gamma_distr$estimate[1],
             rate = gamma_distr$estimate[2]), col="red", add = T)