ggplot2在多個方面突出顯示感興趣的區域

Question

我已經使用Google進行了全面搜索，但只發現此問題「Highlight data individually with facet_grid in R」。

dt <- data.frame(
    a = rep(letters[1:4],each=250), 
    dirct = rep(c("Up","Down"),500), 
    term = rep(letters[1:25],400), 
    logp = runif(1000) 
) 

ggplot(dt,aes(term,logp,fill=dirct))+ 
    facet_grid(.~a) + 
    geom_bar(position="dodge",width=0.8,stat="identity")+ 
    scale_fill_manual("dirct",values=c("red","blue"))+ 
    coord_flip()+ 
    theme(axis.text.y=element_text(colour=c(rep("black",10),rep("red",15))))+ 
    geom_rect(aes(xmin=rep(0.5,1000),xmax=rep(10.5,1000), 
       ymin=-Inf,ymax=Inf),fill="green",alpha=30/200,inherit.aes=FALSE)+ 
    geom_rect(aes(xmin=rep(10.5,1000),xmax=rep(25.5,1000), 
       ymin=-Inf,ymax=Inf),fill="gray",alpha=30/200,inherit.aes=FALSE)+ 
    geom_vline(aes(xintercept=1:25),color="white") + 
    geom_hline(aes(yintercept=seq(0,1,0.25)),color="white") + 
    geom_bar(position="dodge",width=0.8,stat="identity") 

在這裏我已經實現瞭如何突出顯示多個方面的區域。 我的問題是：

是否有可能將感興趣的區域添加爲背景。所以它不需要重畫geom_bar

謝謝你的回覆！

Answer 1

我無法解決barplot的重新繪圖，但我確實設法解決了透明度問題。

green.data <- data.frame(xmin = 0.5, xmax = 10.5, ymin = -Inf, ymax = Inf, a = c("a", "b", "c", "d")) 
# grey.data <- data.frame(xmin = 10.5, xmax = 25.5, ymin = -Inf, ymax = Inf, a = c("a", "b", "c", "d")) 
ggplot() + 
    geom_bar(data = dt, aes(x = term, y = logp, fill = dirct), position = "dodge", width = 0.8, stat = "identity") + 
    geom_rect(data = green.data, aes(xmin = xmin, ymin = ymin, xmax = xmax, ymax = ymax), fill = "green", alpha = 15/100) + 
# geom_rect(data = grey.data, aes(xmin = xmin, ymin = ymin, xmax = xmax, ymax = ymax), fill = "grey", alpha = 0.2) + 
    geom_bar(data = dt, aes(x = term, y = logp, fill = dirct), position = "dodge", width = 0.8, stat = "identity") + 
    scale_fill_manual("dirct", values = c("red", "blue")) + 
    coord_flip() + 
    facet_grid(. ~ a)