如何根据计数变量在饼图中将类别组合在一起？

也许您正在寻找forcats::fct_lump_min哪个允许您根据频率将类别归为“其他”类别。集总后，您可以使用 count 来计算集总类别的聚合计数：

category<- c("a", "b", "c", "d", "e")
count<- c(1,1,4,5,1)
df<- data.frame(category, count)

library(ggplot2)
library(forcats)
library(dplyr)

df <- df %>% 
  mutate(category = forcats::fct_lump_min(category, 2, count, other_level = "Unique")) %>% 
  count(category, wt = count, name = "count")

ggplot(df, aes(y=count, x="", fill= category)) + 
  geom_bar(stat="identity") + 
  coord_polar("y", start = 0)