ggplot2绘制自定义注释直方图

直方图是一个简单但功能强大的图，相对于小提琴和雨云图，直方图可能是传达数据的绝佳方式。下面让我们开始绘制图形,喜欢的小伙伴可以关注个人公众号R语言数据分析指南将分享更多实用技能，先行拜谢了

自定义主题

library(tidyverse)
theme_niwot <- function(){
  theme_bw() +
    theme(text = element_text(family = "Helvetica Light"),
          axis.line.x = element_line(color="black"), 
          axis.line.y = element_line(color="black"),
          axis.text.x = element_text(family = "Times",size=12,face="plain"),
          axis.text.y = element_text(family = "Times",size=12,face="plain"),
          panel.border = element_blank(),
          axis.title.x = element_text(margin = margin(t = 10),size=13,
                                      family = "Times",color="black"),
          axis.title.y = element_text(margin = margin(r = 10),size=13,
                                      family = "Times",color="black"),
          panel.grid.major.x = element_blank(),                                          
          panel.grid.minor.x = element_blank(),
          panel.grid.minor.y = element_blank(),
          panel.grid.major.y = element_blank(),  
          plot.margin = unit(c(1, 1, 1, 1), units = ,"cm"),
          legend.text = element_text(size = 12,family ="Times"),          
          legend.title = element_blank(),                          
          legend.key = element_blank(),
          panel.background = element_rect(fill = "white"),
          legend.background = element_rect(color = "black", 
          fill = "transparent",size = 2, linetype = "blank"))
}

自定义绘制直方图

iris %>% ggplot(aes(Sepal.Length))+
  geom_histogram(alpha=0.8,fill="palegreen4",color="black",)+
  theme_niwot()+
  scale_y_continuous(limits = c(0,20),expand = expansion(mult = c(0, 0.1)))+
  geom_vline(xintercept = mean(iris$Sepal.Length),
             linetype = "dotted",
             colour = "palegreen4",size = 1) +
  annotate("text", x = 7, y = 15,
           label = "The mean number of\nSepal.Length observations was 5.843333") +
  geom_curve(aes(x = 5.85, y = 16,yend = 16,xend = 7),
             arrow = arrow(length = unit(0.07, "inch"),
                           ends="first"),size = 0.7,
             color = "grey30", curvature = -0.3) +
  labs(x = "Sepal.Length", y = "Count")

• geom_vline 添加垂直线

geom_vline(xintercept, linetype, color, size)

• annotate 在特定坐标处添加文本注释

• geom_curve 画一条曲线

此图的亮点也许就在于添加曲线进行注释，下一节将详细介绍如何在图片中添加注释曲线