[问答] [继续求助]R合并数据集语句 [推广有奖]

或如下的可用 merge()

> dataA <- data.frame(ID=c("A", "A", "B", "C", "D"))
> dataB <- data.frame(ID=c("A", "B", "C"), Total=c(150, 100, 60))
> setdiff(dataA$ID, dataB$ID)
[1] "D"
> dataB <- rbind(dataB, data.frame(ID="D", Total=0))
> merge(dataA, dataB)
  ID Total
1  A   150
2  A   150
3  B   100
4  C    60
5  D     0

a<-data.frame(id=c("aa","aa","bb","cc","dd"))
b<-data.frame(id=c("aa","bb","cc"),total=c(150,100,60))
c<-merge(a,b, all.x=T)