创建基于另一列

Question

我有一个数据集，看起来像一个子列的列表：

Files   Batch 
filepath1.txt One 
filepath2.txt One 
filepath3.txt One 
filepath4.txt One 
filepath5.txt two 
filepath6.txt two 
filepath7.txt two 
filepath8.txt two 

我想循环在整个数据集（也有一打“批量”类别）的在一个新的变量创建“文件”是基于什么“批量”他们在，一组名为“批量”

即

batch[1] 
filepath1.txt 
filepath2.txt 
filepath3.txt 
filepath4.txt 

batch[2] 
filepath5.txt 
filepath6.txt 
filepath7.txt 
filepath8.txt 

如何做到这一点对我的所有批次组完整的数据集？

Answer 1

split函数似乎是你在找的东西。

> dat <- data.frame(File = paste0("file", 1:10, ".txt"), Batch = rep(c("one", "two"), each = 5)) 
> dat 
     File Batch 
1 file1.txt one 
2 file2.txt one 
3 file3.txt one 
4 file4.txt one 
5 file5.txt one 
6 file6.txt two 
7 file7.txt two 
8 file8.txt two 
9 file9.txt two 
10 file10.txt two 
> split(dat, dat$Batch) 
$one 
     File Batch 
1 file1.txt one 
2 file2.txt one 
3 file3.txt one 
4 file4.txt one 
5 file5.txt one 

$two 
     File Batch 
6 file6.txt two 
7 file7.txt two 
8 file8.txt two 
9 file9.txt two 
10 file10.txt two