ggplot2：将标签添加到百分比图（不是位置=填充，而只是填充）

Question

我想为百分比条形图添加百分比标签

我通过position="fill" (Add percentage labels to a stacked barplot) 和这里 (How to draw stacked bars in ggplot2 that show percentages based on group?) 找到了解决方案，但是，我想为每个组保留相对频率。

这是一个示例图：

# library
library(ggplot2)

# data  
df <- data.frame(group=c("A","A","A","A","B","B","B","C","C"),
                   anon=c("yes","no","no","no","yes","yes","no","no","no"))

# percentage barplot
  ggplot(df, aes(group),fill=anon) + 
    geom_bar(aes(y = (..count..)/sum(..count..),fill=anon)) + 
    scale_y_continuous(labels=scales::percent) +
    ylab("relative frequencies")

^{由reprex package (v0.3.0) 于 2020 年 4 月 19 日创建}

现在我想为每个条形的每个红色和绿色部分添加百分比标签，以便获得“相对相对”（例如，A 组的“是”为 25%）值。 如何才能做到这一点？我是否必须为此更改我的 df 或者这在 ggplot 函数中是否有可能

Answer 1

一种可能的解决方案是计算ggplot2 之外的比例，这里我使用dplyr 来计算这些不同的比例：

library(dplyr)

df_calculated <- df %>% count(group, anon) %>%
  mutate(Percent_col = n / sum(n)) %>%
  group_by(group) %>%
  mutate(Percent = n/sum(n))

# A tibble: 5 x 5
# Groups:   group [3]
  group anon      n Percent_col Percent
  <fct> <fct> <int>       <dbl>   <dbl>
1 A     no        3       0.333   0.75 
2 A     yes       1       0.111   0.25 
3 B     no        1       0.111   0.333
4 B     yes       2       0.222   0.667
5 C     no        2       0.222   1    

然后用geom_col代替geom_bar绘制条形图，geom_text添加各个比例的文字标签：

library(dplyr)
library(ggplot2)

ggplot(df_calculated, aes(x = group, y = Percent_col, fill = anon))+
  geom_col()+
  scale_y_continuous(labels=scales::percent) +
  ylab("relative frequencies")+
  geom_text(aes(label = scales::percent(Percent)), position = position_stack(0.5))+
  geom_text(inherit.aes = FALSE, 
            data = df_calculated %>% 
              group_by(group) %>% 
              summarise(Sum = sum(Percent_col)),
            aes(label = scales::percent(Sum), 
                y = Sum, x = group), vjust = -0.5)

它回答了你的问题吗？