如何改变直方图的y轴，使其成为r中的密度函数？

install.packages("ggplot2")
install.packages("dplyr")
library(ggplot2)
library(dplyr)

ggplot(data, aes(x = variable)) +
  geom_histogram(aes(y = ..density..), bins = 30, fill = "blue", color = "black") +
  theme_minimal()

ggplot(data, aes(x = variable)) +
  geom_histogram(aes(y = ..density..), bins = 30, fill = "blue", color = "black") +
  geom_density(color = "red") +
  theme_minimal()

ggplot(data, aes(x = variable)) +
  geom_histogram(aes(y = ..density..), bins = 30, fill = "blue", color = "black") +
  geom_density(color = "red") +
  labs(title = "Density Histogram", x = "Variable", y = "Density") +
  theme_minimal()