R语言两个字符向量拼接

有如下两个字符串向量
A<- c("S1","S2","S3")
B<- c("AFG","ALB","DZA")

如何将A和B拼接成如下字符串向量：
"AFG.S1"  "AFG.S2"  "AFG.S3"  "ALB.S1"  "ALB.S2"  "ALB.S3"  "DZA.S1"  "DZA.S2"  "DZA.S3"

比较通俗的答案
A<-c("s1","s2","s3")
B<-c("A","B","C")
total<-c()
for(i in 1:length(B))
{ for(j in 1:length(A))
{
  total<-c(total,paste(B,A[j],sep="."))
}
}
total

1. require('tidyverse')
   
2. A <- c("S1","S2","S3")
   
3. B <- c("AFG","ALB","DZA")
   
4. data_frame(A, B) %>%
   
5.   expand(A, B) %>%
   
6.   mutate(var = str_c(B, A, sep = '.')) %>%
   
7.   pull(var)

复制代码

铁锷未残 发表于 2018-10-7 19:59

你这个应该比较高级，看不懂

A<-c("s1","s2","s3")；
B<-c("A","B","C")；
llply(A,function(x) paste(x,combn(B,1),sep = ".")) %>% unlist

千车麦穗 发表于 2020-5-21 20:57
A

应该用的函数是lapply，应该是笔误