在图外设置图例的方法

Posted 2023-02-16

【中文标题】在图外设置图例的方法

【英文标题】：Method for setting the legend outside a plot

【发布时间】：2019-11-02 15:49:49

【问题描述】：

到目前为止，我看到的所有解决方案都涉及手动设置图例的坐标，使其位于绘图之外。我有超过 100 个图，因此希望能够在每个图上重用相同的代码，以将图例默认放置在图之外。

这里有两个数据框，一个包含成功的求职者，一个包含所有申请该职位的人：

Id <- c(1,5,7,9,11,12,13,15,17,18)
Type <- c("Beginner", "Expert", "Intermediate", "Beginner", 
"Professional", "Expert", "Intermediate", "Professional", "Professional", 
"Expert")
Response<- c(0,1,2,2,1,2,1,2,1,1)
Successful <- data.frame(Id, Type, Response)
Successful

#   Successful
Id  Type             Response    
1   Beginner         0
5   Expert           1
7   Intermediate     2
9   Beginner         2
11  Professional     1
12  Expert           2
13  Intermediate     1
15  Professional     2
17  Professional     1
18  Expert           1

Id <- c(1,2,3,4,5,6,7,8,9,10,11,12,13,14,15,16,17,18)
Type <- c("Beginner", "Expert", "Professional", "Beginner", "Expert", 
"Expert", "Intermediate", "Expert", "Beginner", "Intermediate", 
"Professional", "Expert", "Intermediate","Intermediate", "Professional", 
"Beginner", "Professional","Expert")
Response<- c(0,2,2,1,1,0,2,0,2,0,1,2,1,1,2,2,1,1)
AllApplicants <- data.frame(Id, Type, Response)
AllApplicants

#   AllApplicants
Id  Type             Response        
1   Beginner         0
2   Expert           2
3   Professional     2
4   Beginner         1
5   Expert           1
6   Expert           0
7   Intermediate     2
8   Expert           0
9   Beginner         2
10  Intermediate     0
11  Professional     1
12  Expert           2
13  Intermediate     1
14  Intermediate     1
15  Professional     2
16  Beginner         2
17  Professional     1
18  Expert           1

如果我们绘制这些数据的图：

colors <- c("red", "orange", "green")
barplot(round(100*prop.table(table(AllApplicants$Response, 
AllApplicants$Type),2), 1),
    main="Responses of applicants", xlab="Level", ylab= "Proportion", 
    col=colors, legend.text = T)

图例与情节重叠。 我知道可以手动设置图表的边距和图例的位置：

par(mar=c(5.1,4.1,4.1,8))
legend(5,90, legend=c(0,1,2), fill=colors, xpd=T)

但是，如果我在 barplot() 函数中包含 legend.text=TRUE，我希望保留自动生成的图例，并使其自动将图例放置在图的外部和右侧。当我调整绘图大小和缩放时，我还需要它留在那里。

任何帮助将不胜感激！

【参考方案1】：

ggplot2 解决方案会起作用吗？

library(ggplot2)

df <- as.data.frame(round(100*prop.table(table(AllApplicants$Response, AllApplicants$Type),2), 1))

ggplot(df, aes(x=Var2, y=Freq)) + 
geom_col(aes(fill=Var1)) + 
ggtitle("Responses of applicants") + 
theme(plot.title = element_text(hjust=0.5)) + 
xlab("Level") + ylab("Proportion") + 
theme(legend.title = element_blank())