scale_color_manual()用于ggplot中的不同geom

Question

library(tidyverse)

delta <- tibble(
  type = c("alpha", "beta", "gamma"), 
  a = rnorm(3, 5), 
  b = rnorm(3, 6)
  ) %>% 
  mutate(delta = abs(a - b)) %>% 
  gather(`a`, `b`, `delta`, key = "letter", value = "value")


ggplot(delta %>% filter(letter != "delta"), aes(type, value, fill = letter)) +
  geom_col(position = "dodge") + 
  geom_col(data = delta %>% filter(letter == "delta"), width = 0.5) + 
  scale_color_manual("grey", "black", "blue")

我喜欢a和b酒吧是灰色和黑色.而delta酒吧是蓝色的.我该怎么做scale_color_manual()？似乎我上面的语法已关闭.

Answer 1

有两件事需要改变:

1. 既然你已经习惯了fill = letter,你应该使用scale_fill_manual而不是scale_color_manual(如果你曾经使用的话,那将是合适的color = letter).

2. 手动颜色values应作为矢量提供.

library(tidyverse)

delta <- tibble(
  type = c("alpha", "beta", "gamma"), 
  a = rnorm(3, 5), 
  b = rnorm(3, 6)
) %>% 
  mutate(delta = abs(a - b)) %>% 
  gather(`a`, `b`, `delta`, key = "letter", value = "value")


ggplot(delta %>% filter(letter != "delta"), aes(type, value, fill = letter)) +
  geom_col(position = "dodge") + 
  geom_col(data = delta %>% filter(letter == "delta"), width = 0.5) + 
  scale_fill_manual(values = c("grey", "black", "blue"))

^{由reprex包创建于2018-10-08 (v0.2.1)}