在ggplot2中用透明體覆蓋小提琴圖

Question

這是我正在使用的代碼：

library(ggplot2)
coco1<-rnorm(10000,0,1)
coco2<-rnorm(10000,10,5)
coco3<-rnorm(10000,20,10)
coco4<-rnorm(10000,30,20)
decile<-rbinom(10000,3,1/2)+1
coconut<-data.frame(coco1,coco2,coco3,coco4,decile)

p <- ggplot(coconut, aes(factor(decile), coco1))
p <- p + geom_violin(aes(colour = "1"), alpha = .5, size=2)
q <- p + geom_violin(aes(y = coco2, colour = "2"), alpha = .5, size=2)
q <- q + geom_violin(aes(y = coco3, colour = "3"), alpha = .5, size=2)
q <- q + geom_violin(aes(y = coco4, colour = "4"), alpha = .5, size=2)

q

生成此圖像：

注意小提琴的身體是如何在你去的小提琴層下面產生透明度問題的？ 理想情況下，我希望身體的alpha = 0，身體輪廓的alpha = 1。

Answer 1

p <- ggplot(coconut, aes(factor(decile), coco1)) + 
  geom_violin(aes(colour = "1"), fill = NA, size=2) + 
  geom_violin(aes(y = coco2, colour = "2"), fill = NA, size=2) +
  geom_violin(aes(y = coco3, colour = "3"), fill = NA, size=2) +
  geom_violin(aes(y = coco4, colour = "4"), fill = NA, size=2)

p