r - 避免将 alpha 美学应用于 ggplot2 中的 geom_text

Question

我有以下 ggplot2 图表。我不希望值(value)标签透明。

代码:

ggplot(test, aes(x = reorder(org, -as.numeric(level)), y = obsAvg, fill = level, alpha = round)) + 
  geom_bar(stat = "identity", position = "dodge") +
  scale_fill_manual(values = c("#E69F00", "#56B4E9", "#009E73")) +
  scale_alpha_manual(values = c(.5, .75, 1), guide = FALSE) + 
  labs(title = "Average Observation Score by Round", y = "", x = "", fill = "Group") +
  theme_bw() +
  geom_text(aes(label = round(obsAvg,1)), vjust = -.5, size = 4, fontface="bold", position = position_dodge(width = .9)) +
  scale_y_continuous(limits = c(0,4), expand = c(0,0)) +
  theme(legend.position="bottom")

数据:

set.seed(1)
test <- data.frame(
  org = rep(c("Mammals", "Cats", "Tigers", "Lions", "Cheetahs"), 3),
  level = rep(c("Animals", "Family", rep("Species", 3)), 3),
  group = rep("Cats",15),
  round = rep(c("Round1", "Round2", "Round3"),5),
  obsAvg = runif(15, 1, 4)
)

我曾尝试将 alpha = round 移动为 geom_bar() 的美学，但后来我失去了标签的闪避:

如何复制顶部图表但不将透明美学应用于我的标签？

Answer 1

我会将 aes(alpha=) 移动到 geom_bar，然后将 aes(group=) 添加到 geom_text 恢复闪避。

ggplot(test, aes(x = reorder(org, -as.numeric(level)), y = obsAvg, fill = level)) + 
  geom_bar(aes(alpha=round), stat = "identity", position = "dodge") +
  scale_fill_manual(values = c("#E69F00", "#56B4E9", "#009E73")) +
  scale_alpha_manual(values = c(.5, .75, 1), guide = FALSE) + 
  labs(title = "Average Observation Score by Round", y = "", x = "", fill = "Group") +
  theme_bw() +
  geom_text(aes(label = round(obsAvg,1), group=round), vjust = -.5, size = 4, fontface="bold", position = position_dodge(width = .9)) +
  scale_y_continuous(limits = c(0,4), expand = c(0,0)) +
  theme(legend.position="bottom")

这是一个漂亮的情节。