使用facet_wrap和geom_segment删除不必要的y轴点

我使用以下命令将 y 轴点映射到 x 轴geom_segment()然后使用facet_wrap将数据分成两个图；然而，y 轴点都显示在这两个图上。

我怎样才能只拥有与每个相关的必要的 y 轴点facet_wrap?

示例代码

dat <- structure(list(temp = c(1, 2, 3, 4, 5, 1, 2, 3, 4, 5, 1, 2, 3, 
4, 5, 1, 2, 3, 4, 5, 1, 2, 3, 4, 5, 1, 2, 3, 4, 5), rev = c(-5, 
-11, -20, -29, -40, -9, -20, -32, -45, -57, -12, -24, -37, -50, 
-62, -7, -20, -36, -52, -67, -5, -13, -23, -35, -47, -12, -24, 
-36, -48, -58), type = c("Type 1", "Type 1", "Type 1", "Type 1", 
"Type 1", "Type 1", "Type 1", "Type 1", "Type 1", "Type 1", "Type 1", 
"Type 1", "Type 1", "Type 1", "Type 1", "Type 2", "Type 2", "Type 2", 
"Type 2", "Type 2", "Type 2", "Type 2", "Type 2", "Type 2", "Type 2", 
"Type 2", "Type 2", "Type 2", "Type 2", "Type 2"), model = c("A", 
"A", "A", "A", "A", "B", "B", "B", "B", "B", "C", "C", "C", "C", 
"C", "A", "A", "A", "A", "A", "B", "B", "B", "B", "B", "C", "C", 
"C", "C", "C")), .Names = c("temp", "rev", "type", "model"), row.names = c(NA, 
-30L), class = "data.frame")

p1 <- ggplot(dat, aes(temp, rev, color = model)) + 
  geom_line() + geom_point() + geom_segment(aes(x = 0, xend = temp, yend = rev), linetype = "dashed", color = "grey") + 
  facet_wrap(~type, scales = "free") + scale_y_continuous(breaks = dat$rev)
p1

Plot

我编造了虚拟数据，因为出于某种原因粘贴了你的dput进入我的控制台让它不高兴。

library(dplyr)

df <- expand.grid(temp = 1:5, model = LETTERS[1:3], type = 1:2) %>% 
  group_by(model, type) %>% 
  mutate(rev = -sort(sample.int(20, length(temp)))) 

# this is equivalent to your data as-is, structurewise

df.labeled <- df %>% 
  ungroup() %>% group_by(type, rev) %>% 
  mutate(label = c(rev[1], rep(NA, length(rev) - 1)))

在这里，我为每个组面板中显示的每个 y 值创建了一个组。然后我创建一个label由该 y 值的 1 个观察值组成的列，填充为NAs。因此，如果一个面板有两个模型，每个模型都有一个rev of -5，现在将是-5, NA代替-5, -5。我为什么这样做将在下面变得更清楚。

ggplot(df.labeled, aes(temp, rev, color = model)) + 
  geom_segment(aes(xend = 0, yend = rev), linetype = "dashed", color = "grey") +
  geom_text(aes(label = label, x = -0.1), colour = "black", hjust = 1) +
  geom_vline(xintercept = 0) +
  geom_point() + geom_line() + facet_grid(~type) + 
  scale_y_continuous(breaks = NULL) + 
  scale_x_continuous(limits = c(-0.5, NA)) +
  theme_bw() + theme(panel.grid = element_blank())

如果我保留了重复项（此处类型 1 为 -7、-15，类型 2 为 -11），则geom_text会是一个混乱的粗体模糊。重复的文本标签无法很好地呈现ggplot2。由于实际上不可能按照您想要的方式进行操作，因此这里我们只是为每个面板制作一个假比例。如果您不喜欢数字左侧 y 轴上有一条额外的线，可以将其删除：

  ... + 
  theme(panel.grid = element_blank(),
        panel.border = element_blank(),
        axis.line.x = element_line())