之前画双Y轴的图都是自己写函数用ggplot2去制作，偶然间发现了ggpubr包一种可视化的形式，大家可以一起学习下~

加载包构建数据

library(ggpubr)
library(cowplot)
set.seed(1234)
wdata = data.frame(
  sex = factor(rep(c("F", "M"), each=200)),
  weight = c(rnorm(200, 55), rnorm(200, 58)))
head(wdata)

基础直方图

# Basic histogram without the density curve
gghistogram(
  wdata, x = "weight", 
  add = "mean", rug = TRUE,
  fill = "sex", palette = c("#00AFBB", "#E7B800")
)


# Add the density curve on the same axis
gghistogram(
  wdata, x = "weight", y = "..density..",
  add = "mean", rug = TRUE,
  fill = "sex", palette = c("#00AFBB", "#E7B800"),
  add_density = TRUE
)

图片.png

绘制双 Y 轴

原理其实就是先绘制直方图，再绘制密度图，将Y轴放在右侧，X轴的内容删除，合并起来即可

# 1. Create the histogram plot
phist <- gghistogram(
  wdata, x = "weight", 
  add = "mean", rug = TRUE,
  fill = "sex", palette = c("#00AFBB", "#E7B800")
)

# 2. Create the density plot with y-axis on the right
# Remove x axis elements
pdensity <- ggdensity(
  wdata, x = "weight", 
  color= "sex", palette = c("#00AFBB", "#E7B800"),
  alpha = 0
) +
  scale_y_continuous(expand = expansion(mult = c(0, 0.05)), position = "right")  +
  theme_half_open(11, rel_small = 1) +
  rremove("x.axis")+
  rremove("xlab") +
  rremove("x.text") +
  rremove("x.ticks") +
  rremove("legend")

# 3. Align the two plots and then overlay them.
aligned_plots <- align_plots(g1,g2, align="hv", axis="tblr")
ggdraw(aligned_plots[[1]]) + draw_plot(aligned_plots[[2]])

图片.png

参考链接：https://www.datanovia.com/en/blog/ggplot-histogram-with-density-curve-in-r-using-secondary-y-axis/](https://www.datanovia.com/en/blog/ggplot-histogram-with-density-curve-in-r-using-secondary-y-axis/)