使用由不同变量指示的填充和轮廓颜色创建ggplot条形图/直方图

Question

我正试图在ggplot中创建一个图表：

...其中框的颜色由一个变量表示，框的轮廓由另一个变量表示。

假设数据的结构如下：

df<-data.frame(index=1:50,date=sample(seq(as.Date('1999/01/01'), as.Date('1999/06/01'), by="day"), 50,replace=T),
           V1=sample(c("Indigenous","Import-related","Imported","Unknown"), 50,replace=T),
           V2=sample(c(NA,"Zombie","Pulmonary Hemorrhage"), 50,replace=T))

我能想到的就是这样：

require(ggplot2)
#draw the histogram with fill determined by V1
p<-ggplot(data=df)+geom_histogram(aes(x=date,group=V1,fill=V1),binwidth=7,color="black",alpha=0.9)
#draw the individual boxes for each case
p1<-p+scale_fill_discrete()+geom_histogram(aes(x=date,group=index),binwidth=7,color="black",alpha=0)
#attempt to draw green boxes for one value of V2
p2<-p1+geom_histogram(aes(x=date,group=V2=="Zombie"),binwidth=7,color="green",alpha=0,size=1.2)
#attempt to draw orange boxes for the other value of V2
p3<-p2+geom_histogram(aes(x=date,group=V2=="Pulmonary Hemorrhage"),binwidth=7,color="orange",alpha=0,size=1.2)

然而，这不起作用，因为它在任何地方划定边界，我无法使用这种方法隔离个别案例，如您所见。

是否有ggplot解决方案？如果我不能做彩色框，我可以通过适当的方框上的某种文字注释来指示V2，但是然后必须为每个标签找出x和y，这样就可以让我适合好。

Answer 1

我们可以这样尝试

df<-data.table(index=1:50,date=sample(seq(as.Date('1999/01/01'), as.Date('1999/06/01'), by="day"), 50,replace=T),
               V1=sample(c("Indigenous","Import-related","Imported","Unknown"), 50,replace=T),
               V2=sample(c(NA,"Zombie","Pulmonary Hemorrhage"), 50,replace=T))

df <- df[,.(count=.N), by = .(date,V1,V2)]

windows()
ggplot(data = df, aes(x = date, y = count, color = V2, fill = V1)) +
  geom_bar(stat = "identity", position = "stack", width = 2, size = 1) + 
  scale_fill_manual(values=c("red4", "blue4", "green4", "blue")) + 
  scale_color_manual(values=c("orange", "green", "black")) +
  scale_y_continuous(breaks = seq(1,3,1))