使用构面时创建动态 x 轴标签

Question

我有一个 plot 它使用如下所示的方面：

library(tidyverse)

dat <- data.frame(grp = c("a", "a", "b", "b"),
           ep = c("r1", "r2", "r1", "r2"),
           val = c(3, 5, 2, 5),
           suffix = c("_w", "_x", "_y", "_z"))

dat %>% 
  ggplot(aes(x = ep, y = val, fill = ep)) +
  geom_col(position = "dodge") + 
  facet_wrap(~grp)

我想 append 每个 x 轴标签的后缀列，因此最终结果将如下所示：

我在下面尝试过这种方法，但是说找不到后缀变量：

dat %>% 
  ggplot(aes(x = ep, y = val, fill = ep)) +
  geom_col(position = "dodge") + 
  scale_x_discrete(labels = function(x) paste0(x, suffix)) +
  facet_wrap(~grp)

Answer 1

不要在ggplot中做，先创建后缀列。

library(tidyverse)

dat <- data.frame(grp = c("a", "a", "b", "b"),
                  ep = c("r1", "r2", "r1", "r2"),
                  val = c(3, 5, 2, 5),
                  suffix = c("_w", "_x", "_y", "_z"))

dat %>% 
  mutate(x_suffix = paste0(ep, suffix)) %>%
  ggplot(aes(x = x_suffix, y = val, fill = ep)) +
  geom_col(position = "dodge") + 
  facet_wrap(~grp, scales = "free_x")

^{由reprex package (v2.0.1) 于 2021 年 12 月 1 日创建}