我有以下数据框：
V1 subst_string
1 NM_000171 L374R
2 NM_000171 W421P
3 NM_000171 T358A
4 NM_000171 T358A
5 NM_000171 T358A
6 NM_000171 T358A
7 NM_000171 S268R
8 NM_000171 N35P
9 NM_000171 T435F
10 NM_000171 T435F
11 NM_000171 T435F
12 NM_000171 T435F
13 NM_000171 L368E
14 NM_000171 L368G
15 NM_000171 L374R
16 NM_000171 W421L
17 NM_000171 W421P
18 NM_000171 W421L
19 NM_000171 R371R
20 NM_000171 R371R
21 NM_000171 S268R
22 NM_000171 N35R
23 NM_000171 N35P
24 NM_000171 N35R
25 NM_000171 F271L
26 NM_000171 F271L
27 NM_000171 F271L
28 NM_000171 L368E
29 NM_000171 L374R
30 NM_000171 L374R
31 NM_000171 M157N
32 NM_000171 M157N
33 NM_000171 M157N
34 NM_000171 R371R
35 NM_000171 S268R
36 NM_000171 S268R
37 NM_000171 Y201P
38 NM_000171 Y201P
39 NM_000171 Y201P
40 NM_000171 Y201P
41 NM_000171 F271L
42 NM_000171 L368G
43 NM_000171 Y397S
44 NM_000171 Y397G
45 NM_000171 Y397S
46 NM_000171 Y397G
47 NM_000171 M157N
48 NM_000171 R371R
49 NM_001146040 F271L
50 NM_001146040 L368E
51 NM_001146040 L374R
52 NM_001146040 E429P
53 NM_001146040 T358A
54 NM_001146040 T358A
55 NM_001146040 M157N
56 NM_001146040 R371R
57 NM_001146040 S268R
58 NM_001146040 N35P
59 NM_001146040 I443F
60 NM_001146040 I443F
61 NM_001146040 Y201P
62 NM_001146040 Y201P
63 NM_001146040 F271L
64 NM_001146040 L368G
65 NM_001146040 L374R
66 NM_001146040 E429L
67 NM_001146040 L405S
68 NM_001146040 L405G
69 NM_001146040 M157N
70 NM_001146040 R371R
71 NM_001146040 S268R
72 NM_001146040 N35R
73 NM_001292000 NANANA
74 XM_005268412 NANANA
这很简单 - 第一列由4个不同的值组成，我想创建4个数据子集，其中数据帧由这些不同的值进行子集化。即。
V1 subst_string
1 NM_000171 L374R
2 NM_000171 W421P
3 NM_000171 T358A
4 NM_000171 T358A
5 NM_000171 T358A
6 NM_000171 T358A
7 NM_000171 S268R
8 NM_000171 N35P
9 NM_000171 T435F
10 NM_000171 T435F
11 NM_000171 T435F
12 NM_000171 T435F
13 NM_000171 L368E
14 NM_000171 L368G
15 NM_000171 L374R
16 NM_000171 W421L
17 NM_000171 W421P
18 NM_000171 W421L
19 NM_000171 R371R
20 NM_000171 R371R
21 NM_000171 S268R
22 NM_000171 N35R
23 NM_000171 N35P
24 NM_000171 N35R
25 NM_000171 F271L
26 NM_000171 F271L
27 NM_000171 F271L
28 NM_000171 L368E
29 NM_000171 L374R
30 NM_000171 L374R
31 NM_000171 M157N
32 NM_000171 M157N
33 NM_000171 M157N
34 NM_000171 R371R
35 NM_000171 S268R
36 NM_000171 S268R
37 NM_000171 Y201P
38 NM_000171 Y201P
39 NM_000171 Y201P
40 NM_000171 Y201P
41 NM_000171 F271L
42 NM_000171 L368G
43 NM_000171 Y397S
44 NM_000171 Y397G
45 NM_000171 Y397S
46 NM_000171 Y397G
47 NM_000171 M157N
48 NM_000171 R371R
将是一个这样的子集。我想我可以做这个manuall，但是我设想在后来的数据集中有更多不同的V1值。有没有人知道如何基于V1的不同值自动生成此数据帧的子集？
谢谢
答案 0 :(得分：4)
只需使用split即可创建list
split(df, df$V1)
如果您需要全球环境中的4个数据集
list2env(split(df, df$V1), envir=.GlobalEnv)
head(NM_000171,2)
# V1 subst_string
#1 NM_000171 L374R
#2 NM_000171 W421P
答案 1 :(得分：3)
如果你知道拆分后要做什么，有很多方法;而你不需要使用'拆分'。例如，要查找子组的长度：
with(ddf, tapply(subst_string, V1, length))
NM_000171 NM_001146040 NM_001292000 XM_005268412
48 24 1 1
aggregate(subst_string~V1, data=ddf, length)
V1 subst_string
1 NM_000171 48
2 NM_001146040 24
3 NM_001292000 1
4 XM_005268412 1
library(data.table)
ddt = data.table(ddf)
ddt[,list(len =.N),by=V1]
V1 len
1: NM_000171 48
2: NM_001146040 24
3: NM_001292000 1
4: XM_005268412 1