基于strsplit将数据帧重组为多行

我有这样的数据结构

    structure(list(id = c("4031", "1040;2040;3040", "4040", 
    "1050;2050;3050"), description = c("Sentence A", 
    "Sentence B", "Sentence C", 
    "Sentence D")), row.names = 1:4, class = "data.frame")

              id description
1           4031  Sentence A
2 1040;2040;3040  Sentence B
3           4040  Sentence C
4 1050;2050;3050  Sentence D

我希望重新构造数据，以便将带有“；”的ID拆分为单独的行-我希望这样：

structure(list(id = c("4031", "1040","2040","3040", "4040", 
"1050","2050","3050"), description = c("Sentence A", 
"Sentence B","Sentence B","Sentence B", "Sentence C", 
"Sentence D","Sentence D","Sentence D")), row.names = 1:8, class = "data.frame")

   id description
1 4031  Sentence A
2 1040  Sentence B
3 2040  Sentence B
4 3040  Sentence B
5 4040  Sentence C
6 1050  Sentence D
7 2050  Sentence D
8 3050  Sentence D

我知道我可以使用

strsplit

拆分id列，但无法找到一种有效的方法，在没有循环的情况下将其转换为行

strsplit( as.character( a$id ) , ";" )

---

使用

tidyr

的一个非常方便的可能性是：

separate_rows(df, id)

    id description
1 4031  Sentence A
2 1040  Sentence B
3 2040  Sentence B
4 3040  Sentence B
5 4040  Sentence C
6 1050  Sentence D
7 2050  Sentence D
8 3050  Sentence D

使用R基：

> IDs <- strsplit(df$id, ";")
> data.frame(ID=unlist(IDs), Description=rep(df$description, lengths(IDs)))
    ID Description
1 4031  Sentence A
2 1040  Sentence B
3 2040  Sentence B
4 3040  Sentence B
5 4040  Sentence C
6 1050  Sentence D
7 2050  Sentence D
8 3050  Sentence D

IDs data.frame（ID=unlist（IDs），Description=rep（df$Description，length（IDs））） ID描述 14031 A句 21040 B句 3 2040 B句 43040 B句 54040 C句 61050 D句 7 2050 D句 83050句D