How to unsplit a split in R data frame?

To unsplit a split in R data frame, we can follow the below steps −

• First of all, create a data frame.

• Then, use split function to split the data frame.

• After that, use do.call function along with rbind function unsplit the data frame.

Example

Create the data frame

Let’s create a data frame as shown below −

x<-rpois(25,5)
y<-rpois(25,5)
z<-rpois(25,5)
df<-data.frame(x,y,z)
df

Output

On executing, the above script generates the below output(this output will vary on your system due to randomization) −

   x y z
1  4 3 3
2  5 2 3
3  5 6 3
4  9 2 5
5  8 5 5
6  3 6 5
7  6 3 4
8  2 2 5
9  2 6 4
10 6 6 4
11 2 9 5
12 4 11 4
13 5 3 5
14 6 4 6
15 3 6 4
16 4 6 5
17 6 2 8
18 3 6 5
19 5 7 6
20 2 5 3
21 3 8 5
22 7 5 6
23 1 6 3
24 7 3 6
25 4 3 5

Split the data frame

Using split function to split the data frame −

x<-rpois(25,5)
y<-rpois(25,5)
z<-rpois(25,5)
df<-data.frame(x,y,z)
new_df<-split(df,df$x)
new_df

Output

$ `2`
   x y z
12 2 4 6

$`3`
   x y z
14 3 6 4
15 3 5 5
21 3 6 5

$`4`
    x  y z
 2  4 10 6
 4  4  7 3
 7  4  7 7
 8  4  2 3
11  4  4 4
13  4  3 4
16  4  3 4
19  4  2 2
23  4  3 6

$`5`
   x y z
1  5 3 4
25 5 9 3

$`6`
  x y z
5 6 7 0
6 6 1 8

$`7`
    x y z
3  7 7 1
9  7 3 0
18 7 2 4
22 7 9 4
24 7 9 2

$`8`
   x y z
10 8 3 4

$`9`
   x y z
20 9 2 2

$`10`
    x y z
17 10 7 9

Unsplit the data frame

Using do.call function along with rbind function unsplit the data frame df −

x<-rpois(25,5)
y<-rpois(25,5)
z<-rpois(25,5)
df<-data.frame(x,y,z)
new_df<-split(df,df$x)
do.call("rbind",new_df)

Output

      x y z
2.13  2 7 6
2.24  2 9 5
3.5   3 2 5
3.9   3 7 2
3.11  3 3 2
3.19  3 3 8
3.20  3 5 3
4.2   4 2 4
4.3   4 3 6
4.4   4 4 1
4.25  4 8 6
5.7   5 2 5
5.8   5 4 8
5.14  5 4 5
5.15  5 4 4
5.21  5 9 2
6.1   6 8 5
6.17  6 6 5
6.18  6 2 4
7     7 8 3
8.10  8 5 4
8.16  8 6 6
9.12  9 3 4
9.22  9 4 6
9.23  9 8 5

Nizamuddin Siddiqui

Published on 11-Nov-2021 05:44:11

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