r - 有没有办法在同一个 ggplot 上使用 2 个色标？

Question

将数据按类别（样本 A 和 B）分开，制作了 2 层，一层用于点，一层用于线。我想按类别分隔我的数据，指示点的颜色，并分隔线，但颜色与用于点的颜色不同。

library(ggplot2)

Sample <- c("a", "b")
Time <- c(0,1,2)

df <- expand.grid(Time=Time, Sample = Sample)
df$Value <- c(1,2,3,2,4,6)

ggplot(data = df,
             aes(x = Time,
                 y = Value)) +
  geom_point(aes(color = Sample)) +
  geom_line(aes(color = Sample)) +
  scale_color_manual(values = c("red", "blue")) + #for poits
  scale_color_manual(values = c("orange", "purple")) #for lines

Answer 1

使用ggnewscale包可以这样实现：

library(ggplot2)
library(ggnewscale)
Sample <- c("a", "b")
Time <- c(0,1,2)

df <- expand.grid(Time=Time, Sample = Sample)
df$Value <- c(1,2,3,2,4,6)

ggplot(data = df,
       aes(x = Time,
           y = Value)) +
  geom_point(aes(color = Sample)) +
  scale_color_manual(name = "points", values = c("red", "blue")) + #for poits
  new_scale_color() +
  geom_line(aes(color = Sample)) +
  scale_color_manual(name = "lines", values = c("orange", "purple")) #for lines

Answer 2

使用颜色列和scale_color_identity：

df$myCol1 <- rep(c("red", "blue"), each = 3)
df$myCol2 <- rep(c("orange", "purple"), each = 3)

ggplot(data = df,
       aes(x = Time,
           y = Value)) +
  geom_point(aes(color = myCol1)) +
  geom_line(aes(color = myCol2)) +
  scale_color_identity()