使用 facet_wrap() 时在 ggplot 中手动标记轴

Question

我正在尝试手动标记我的 x 轴，但是当我刻面我的图并释放我的 x 轴的比例时，标签变得不正确。我想知道是否有办法防止这种情况发生，而不必事先手动更改我的字符串。

当我使用 scale_x_discrete() 手动标记 x 轴时，标签是正确的

library(tidyverse)

df <- data.frame(trial = rep(c("a", "b", "c"), each = 30),
                 values = rnorm(n = 90, mean = 0, sd = 1),
                 variable = c(rep("n", times = 60), rep("m", times = 30))
                 )

df %>%
  ggplot(aes(x = trial, y = values)) +
  geom_violin(aes(fill = trial)) +
  scale_x_discrete(labels = c("A", "B", "C")) +
  theme(legend.position = "none") 

Plot 1

但是，当我处理我的情节时，标签变得不正确。

df %>%
  ggplot(aes(x = trial, y = values)) +
  geom_violin(aes(fill = trial)) +
  scale_x_discrete(labels = c("A", "B", "C")) +
  facet_wrap(~ variable, scales = "free_x") +
  theme(legend.position = "none")

Plot 2

Answer 1

试试这个：

library(ggplot2)
library(dplyr)
#Code
df %>%
  ggplot(aes(x = trial, y = values)) +
  geom_violin(aes(fill = trial)) +
  scale_x_discrete(breaks=c('a','b','c'),labels = c("A", "B", "C")) +
  facet_wrap(~ variable, scales = "free_x") +
  theme(legend.position = "none")

输出：

或者您也可以尝试使用mutate() 格式化变量：

#Code 2
df %>%
  mutate(trial=factor(trial,levels = unique(trial),labels = c("A", "B", "C"))) %>%
  ggplot(aes(x = trial, y = values)) +
  geom_violin(aes(fill = trial)) +
  facet_wrap(~ variable, scales = "free_x") +
  theme(legend.position = "none")

相同的输出。或者听从 @cookesd 的建议（非常感谢并感谢他）：

#Code 3
df %>%
  ggplot(aes(x = trial, y = values)) +
  geom_violin(aes(fill = trial)) +
  scale_x_discrete(labels = c('a' = 'A', 'b' = 'B', 'c' = 'C')) +
  facet_wrap(~ variable, scales = "free_x") +
  theme(legend.position = "none")

同样的输出。

Answer 2

我们可以从forcats使用fct_recode

library(forcats)
library(dplyr)
library(ggplot2)
df %>% 
   mutate(trial = fct_recode(trial, A= 'a', B = 'b', C = 'c'))  %>% 
  ggplot(aes(x = trial, y = values)) + 
       geom_violin(aes(fill = trial)) +
       facet_wrap(~ variable, scales = "free_x") + 
       theme(legend.position = "none")

-输出