r - 在ggplot中拆分y轴

Question

我的数据结构类似于以下结构:

data.frame(x = c("A", "B", "C", "D", "E"), 
           a = abs(rnorm(5)), 
           b = abs(rnorm(5)))

我想以以下方式显示它(请原谅糟糕的油漆工作):


为此，我编写了以下代码:

set.seed(20)
data.frame(x = c("A", "B", "C", "D", "E"), 
           a = abs(rnorm(5)), 
           b = abs(rnorm(5))) %>%
  mutate(b = -b) %>%
  gather("source", "amount", a, b) %>%
  ggplot(aes(x = x,
             y = amount,
             fill = source)) +
  geom_col() +
  scale_y_continuous(labels = abs)

这给了我以下内容:



我将如何沿 y = 0 添加间隙并用 x 轴标签填充它？

Answer 1

我们可以通过将它们移动到 facet 来获得大部分方法:

set.seed(20)
data.frame(x = c("A", "B", "C", "D", "E"), 
           a = abs(rnorm(5)), 
           b = abs(rnorm(5))) %>%
  mutate(b = -b) %>%
  gather("source", "amount", a, b) %>%
  ggplot(aes(x = x,
             y = amount,
             fill = source)) +
  geom_col() + 
  scale_y_continuous(labels = abs) +

  # NEW STUFF:
  facet_wrap(~source, ncol=1, scales = "free_y") +
  theme(strip.text = element_blank())

这是通过制作一层 geom_text 在中间获得 x 轴标签的方法。并将其放置在顶部刻面下方的 y 范围内。我不知道一个好的“内置”方式来做到这一点。

data.frame(x = c("A", "B", "C", "D", "E"), 
           a = abs(rnorm(5)), 
           b = abs(rnorm(5))) %>%
  mutate(b = -b) %>%
  gather("source", "amount", a, b) %>%
  ggplot(data = .,
         aes(x = x,
             y = amount,
             fill = source)) +
  geom_col() + 

  # removing minor_breaks avoids grid lines in the middle space
  scale_y_continuous(labels = abs, minor_breaks = NULL) +
  # this creates a single copy of the text, related to one facet
  geom_text(data = . %>% filter(source == "a"), aes(x, y = -.2, label = x)) +
  # this allows for printing outside the plot range
  coord_cartesian(clip = "off") +
  facet_wrap(~source, ncol=1, scales = "free_y", shrink = TRUE ) +
  theme(strip.text = element_blank(),
        axis.text.x = element_blank())