生成两列逗号分隔字符的组合

Question

我有一个（示例）数据框，包括一个标识符（此处为“ID”）和两个感兴趣的变量（此处为“V1”和“V2”）：

df <- data.frame(ID = c("Sample 1", "Sample 2", "Sample 3"), 
                 V1 = c("A, B, C",  "E"       , "A, F"),
                 V2 = c("H, G"   ,  "C, A"    , "J"))

对于感兴趣的两个变量（即列），我想生成逗号分隔字符的所有潜在组合，可通过标识符进行识别（通过行偏角）。

结果数据框可能看起来像这样（只要组合完整，顺序和结构上的一些灵活性是可以接受的）：

rd <- data.frame(ID = c("Sample 1","Sample 1", "Sample 1", "Sample 1", "Sample 1", "Sample 1", "Sample 2", "Sample 2", "Sample 3", "Sample 3"),
                 V1 = c("A", "A", "B", "B", "C", "C", "E", "E", "A", "F"),
                 V2 = c("H","G","H","G","H","G","C","A","J","J"))

非常感谢您的支持。

Answer 1

library(tidyr)
df  |>
  separate_rows(V1) |>
  separate_rows(V2)

结果

         ID V1 V2
1  Sample 1  A  H
2  Sample 1  A  G
3  Sample 1  B  H
4  Sample 1  B  G
5  Sample 1  C  H
6  Sample 1  C  G
7  Sample 2  E  C
8  Sample 2  E  A
9  Sample 3  A  J
10 Sample 3  F  J