如何在ggplot2中为多行添加标签？

如何解决如何在ggplot2中为多行添加标签？

我有一个df1：

 Year      V1        UR  CR         PA           FO  NA       TOTALLU
1   1850 7377211     0 0.03615170 0.1405466      0 0.8232772 0.9999755
2   1851 7377212     0 0.03622309 0.1397468      0 0.8240073 0.9999771
3   1852 7377213     0 0.03631065 0.1389448      0 0.8247278 0.9999833
4   1853 7377214     0 0.03639766 0.1381439      0 0.8254495 0.9999911
5   1854 7377215     0 0.03647239 0.1373441      0 0.8261718 0.9999883
6   1855 7377216     0 0.03655438 0.1365248      0 0.8269085 0.9999877

如何在一张图中绘制CR，PA和NA的3条时间线，并添加标签。我正在这样做，但是我的标签仅适用于两个变量

ggplot(df1,aes(x=Year),ylim=c(0,1)) + 
geom_line(aes(y = CR),color = "red")+ 
geom_line(aes(y = PA,color="blue"))+
geom_line(aes(y = NA,color="green"))+
  scale_y_continuous(limits = c(0,1))+ylab("LU")

解决方法

您可以使用directlabels和ggplot2尝试这种方法。在这里，您必须将代码整形为长，然后使用geom_line()添加行。如果您希望每行有一个标签，则可以使用geom_dl()。接下来的解决方案（我只选择了您提到的变量，但可以对其进行修改）：

library(ggplot2)
library(dplyr)
library(tidyr)
library(directlabels)
#Code
df %>% select(c(1,4,5,7)) %>%
  pivot_longer(cols = -1) %>%
  ggplot(aes(x=factor(Year),y=value,color=name,group=name))+
  geom_line()+
  geom_dl(aes(label = name),method = list(dl.trans(x = x + 0.2),"last.points",cex = 0.8,fontface='bold'))

输出：

使用了一些数据：

#Data
df <- structure(list(Year = 1850:1855,V1 = 7377211:7377216,UR = c(0L,0L,0L),CR = c(0.0361517,0.03622309,0.03631065,0.03639766,0.03647239,0.03655438),PA = c(0.1405466,0.1397468,0.1389448,0.1381439,0.1373441,0.1365248),FO = c(0L,NA. = c(0.8232772,0.8240073,0.8247278,0.8254495,0.8261718,0.8269085),TOTALLU = c(0.9999755,0.9999771,0.9999833,0.9999911,0.9999883,0.9999877)),class = "data.frame",row.names = c("1","2","3","4","5","6"))