获取数据框中的所有子集并列出R中的所有因子

Question

我面临R中涉及子集的问题。我必须列出R中子集中的所有独特因子，但我一直在通过 for loop 进行。

例如，我有一个数据框如下：

       area         family    
 [1,] "Location 1" "Diaz"    
 [2,] "Location 1" "Santiago"
 [3,] "Location 2" "Peralta" 
 [4,] "Location 2" "Perez"   
 [5,] "Location 2" "Cooper"  
 [6,] "Location 3" "Tesla"   
 [7,] "Location 3" "Tatum"   
 [8,] "Location 4" "Brown"   
 [9,] "Location 4" "Lee"     
 [10,] "Location 4" "Anthony" 

输出所需的内容如下：

[[1]]
[1] "Diaz" "Santiago"

[[2]]
[1] "Peralta" "Perez" "Cooper"

[[3]]
[1] "Tesla" "Tatum"

[[4]]
[1] "Brown" "Lee" "Anthony"

有人可以帮我简化这个过程吗？

谢谢。

Answer 1

我们可以使用split将“家庭”列拆分为list的{​​{1}}中的“区域”列

vector

Answer 2

此外，请考虑by：

by(df, df[, "area"], function(x) x[,"family"])