带百分比的R ggplot

Question

我正在尝试用百分比而不是计数来绘制条形图，而我已经尝试过了：

ggplot(data = newdf3) + 
  geom_bar(mapping = aes(x = key, y = ..prop..,fill=value,group = 1), stat = "count",position=position_dodge()) + 
  scale_y_continuous(labels = scales::percent_format())

但显然“ group = 1”不起作用，因为它返回的是：

，如果我不使用“ group = 1”，它将返回：

这是我正在使用的数据示例：

key   value

1     Before
1     After
1     During
1     Before
2     Before
2     After
3     During
...

有人可以帮我吗？

Answer 1

考虑使用geom_col()代替geom_bar()。

但是，您应该可以解决stat="identity"的问题。

library(ggplot2)

#sample data.frame
df <- data.frame(
  group = c("A","A","B","B","C","C"),
  value = c(0.1,0.5,0.3,0.1,0.2,0.6)
)
df %>% head

#histogram
df %>% 
  ggplot(aes(x = group)) + 
  geom_bar()

#NOT histogram
df %>% 
  ggplot(aes(x = group, y = value)) + 
  geom_bar(stat = "identity") +
  scale_y_continuous(labels = scales::percent_format())

Answer 2

一种解决方案是使用您输入的数据计算相对频率，然后使用ggplot中的stat = "identity"参数将结果直接传递到geom_bar（请参阅this post）：

library(tidyverse)

df <- tibble::tribble(
  ~key, ~value,
  1, "Before",
  1, "After",
  1, "During",
  1, "Before",
  2, "Before",
  2, "After",
  3, "During"
)

df %>%
  dplyr::count(key, value) %>%
  dplyr::group_by(key) %>%
  dplyr::mutate(p = n / sum(n)) %>%
  ggplot() + 
    geom_bar(
      mapping = aes(x = key, y = p, fill = value),
      stat = "identity",
      position = position_dodge()
    ) + 
    scale_y_continuous(labels = scales::percent_format())

^{由reprex package（v0.3.0）于2019-10-28创建}