ggplot2 facets 设置绘图颜色

Question

不确定标题是否恰当地解释了我的问题：使用 facet wraps，我有一个图是其他图的摘要，这导致该图在我绘制颜色的变量上具有更高的值。因此，所有其他图只显示（大部分）一种颜色：Example graph。

我希望着色更依赖于非汇总图，而我不太关心汇总图是否由于包含高值而最终仅显示一种颜色（尽管较低的值仍应显示适当的颜色）。感谢您的帮助。

示例代码：

library(gdata)
library(viridis)
library(ggplot2)
summary <- data.frame(x = 1:15, y = runif(15), z = runif(15, min = 15, max = 200))
dat2 <- data.frame(x = 1:15, y = runif(15), z = runif(15, min = 0, max = 30))
dat3 <- data.frame(x = 1:15, y = runif(15), z = runif(15, min = 0, max = 30))
dat4 <- data.frame(x = 1:15, y = runif(15), z = runif(15, min = 0, max = 30))
dat <- combine(summary, dat2, dat3, dat4)

p <- ggplot(dat, aes(x = x, y = y)) +
geom_point(aes(color = z)) +
scale_color_viridis(option = "magma") +
theme(panel.background = element_rect(fill = "grey93"),
    strip.background = element_blank(),
    panel.grid = element_blank(),
    panel.border = element_rect(fill = NA, colour = "black", size = 0.5, linetype = "solid"))`

p1 <- p +  facet_wrap(~source)

Answer 1

summary <- data.frame(x = 1:15, y = runif(15), z = runif(15, min = 15, max = 200))
dat2 <- data.frame(x = 1:15, y = runif(15), z = runif(15, min = 0, max = 30))
dat3 <- data.frame(x = 1:15, y = runif(15), z = runif(15, min = 0, max = 30))
dat4 <- data.frame(x = 1:15, y = runif(15), z = runif(15, min = 0, max = 30))
dat <- combine(summary, dat2, dat3, dat4)
dat_ <- subset(dat, source != "summary")

cut_off <- 70 # adjust here where you want the cut-off of z values to be.
summary2 <- subset(dat, source == "summary" & z < cut_off) 

p <- ggplot(dat_, aes(x = x, y = y)) +
 geom_point(aes(color = z)) +
 geom_point(data = summary2, aes(col = z)) +
 scale_color_viridis(option = "magma") +
 theme(panel.background = element_rect(fill = "grey93"),
       strip.background = element_blank(),
       panel.grid = element_blank(),
       panel.border = element_rect(fill = NA, colour = "black", size = 0.5, linetype = "solid"))

p1 <- p +  facet_wrap(~source)

summary3 <- subset(dat, source == "summary" & z >= cut_off)
p1 + geom_point(data = summary3, col = "red") # adjust the color aesthetic of the highest summary graph points here.

所以您会看到，在汇总图中 z 值大于或等于 70 的汇总数据用“红色”着色，因此它们与绿色岩浆规模形成对比。 （用“白色”做实验，它也有很好的对比）。 z 值小于 70 的所有汇总数据观察值将遵循与汇总图中其他三个图表相同的色标。降低 cut_off 变量（当前设置为 70）以在 dat2、dat3 和 dat4 图中获得更多颜色。

这正是您一直在寻找的答案。