r - 修改ggplot2中圆环图百分比标签的位置和格式

Question

我用下面的代码绘制了一个 donut chart :

library(tidyverse)
library(ggthemes)

df <- data.frame(flavor = c("Chocolate", "Strawberry", "Pistachio"),
                        per_sold = c(.20, .30, .50))
df %>%
  ggplot(aes(x = 2, y = per_sold, fill = flavor)) +
  geom_bar(stat = "identity") +
  xlim(0.5, 2.5) +
  coord_polar(start = 0, theta = "y") +
  xlab("") +
  ylab("") +
  theme(axis.ticks = element_blank(),
        axis.text = element_blank(),
        axis.title = element_blank(),
        panel.grid = element_blank(),
        panel.border = element_blank(),
        legend.title = element_text(size = rel(2)),
        legend.text=element_text(size=rel(1.5))) +
  geom_text(aes(label = per_sold), size = 6)

出去:

如您所见，标签的位置不正确，我希望它显示 % 的格式而不是带数字的浮点数。
我怎样才能修改代码来实现这一点？谢谢。

Answer 1

您只需要position_stack(vjust = 0.5)和 scales::percent :

library(scales)
df %>%
  ggplot(aes(x = 2, y = per_sold, fill = flavor)) +
  geom_bar(stat = "identity") +
  xlim(0.5, 2.5) +
  coord_polar(start = 0, theta = "y") +
  xlab("") +
  ylab("") +
  theme(axis.ticks = element_blank(),
        axis.text = element_blank(),
        axis.title = element_blank(),
        panel.grid = element_blank(),
        panel.border = element_blank(),
        legend.title = element_text(size = rel(2)),
        legend.text=element_text(size=rel(1.5))) +
  geom_text(aes(label = scales::percent(per_sold)),
            size = 6, position = position_stack(vjust = 0.5))