r - 如何在R中的不同方面产生不同的geom_vline？

Question

我正在尝试在数据集的 2 个不同方面生成 2 条具有不同颜色的不同 geom_vlines。我这样做是为了突出两个不同方面的含义。

这是数据集:

Pclass  Sex    Age  SibSp   Parch   Fare    Cabin   Embarked    Survived
  3     male    22   1        0     7.25                S          0    
  1     female  38   1        0    71.2833   C85        C          1
  3     female  26   0        0     7.925               S          1    
  1     female  35   1        0    53.1     C123        S          1
  3     male    35   0        0     8.05                S          0    
  1     male    54   0        0    51.8625   E46        S          0

代码如下:

g<-ggplot(data = train3, aes(x = Age, y = Survived, colour = factor(Pclass)))
g<-g+facet_wrap(~Sex)
g<-g+geom_point(size = 4, alpha = 0.2)+ggtitle("Survival by Gender")+theme(plot.title = element_text(hjust = 0.5))
g<-g+geom_vline(data = subset(train3,Sex=="female"), xintercept = mean(train3[which(train3$Sex=="female"),3]), colour = "pink", size = 1)
g<-g+geom_vline(data = subset(train3,Sex=="male"), xintercept = mean(train3[which(train3$Sex=="male"),3]), colour = "blue", size = 1)
g

这是输出

实际上，我只想在每个方面产生 1 个 vline:雌性为粉红色，雄性为蓝色。

给出的建议here也不工作。显示错误为:

Error in .(Sex == "female") : could not find function "."

Answer 1

以下是如何为不同的鸢尾品种添加不同的geom_vline:

ggplot(iris, aes(Sepal.Length, Petal.Length)) + facet_wrap(~Species, scales="free") + geom_point() + 
  geom_vline(data=filter(iris, Species=="setosa"), aes(xintercept=5), colour="pink") + 
  geom_vline(data=filter(iris, Species=="versicolor"), aes(xintercept=6), colour="blue") + 
  geom_hline(data=filter(iris, Species=="virginica"), aes(yintercept=6), colour="green")