ggplot2。如何使 geom_bar 堆积图 y 范围 0-100%？

Question

使用 stat = "identity" 的 geom_bar 时，y 轴最大值是所有值的总和。在此示例中，我希望 y 轴最大值为 100 而不是 300，并且堆积条形图显示每个复制品的条形比例。有谁知道我该怎么做？

dat = data.frame(sample = c(rep(1, 12),
                            rep(2, 9),
                            rep(3, 6)),
                 category = c(rep(c("A", "B", "C"), each = 4),
                              rep(c("A", "B", "C"), each = 3),
                              rep(c("A", "B", "C"), each = 2)),
                 replicate = c(rep(c("a", "b", "c", "d"), 3),
                               rep(c("a", "b", "c"), 3),
                               rep(c("a", "b"), 3)),
                 value = c(rep(25, 12),
                           rep(c(25, 25, 50), 3),
                           rep(50, 6))
                 )

ggplot(dat, 
       aes(x = sample, y = value)) +
  geom_bar(aes(fill = replicate),
           stat = "identity")

Answer 1

一种方法是在绘图之前预先计算值。

library(dplyr)
library(ggplot2)

dat %>%
   group_by(sample) %>%
   mutate(value = value/sum(value) * 100) %>%
   ggplot() + aes(x = sample, y = value, fill = replicate) +
   geom_col()  +
   ylab('value  %')