How to add suffix to column names in R?

To add suffix to column names in R, we can use paste function. For example, if we have a data frame called df that contains three columns say x, y, and z and we want to add a suffix to these columns say underscore1 (_1) then it can be done by using the command

colnames(df)<-paste(colnames(df),"1",sep="_")

Example1

Consider the below data frame −

Live Demo

> x<-rpois(20,5)
> y<-rpois(20,5)
> z<-rpois(20,5)
> df1<-data.frame(x,y,z)
> df1

Output

   x y z
1  6 3 2
2  9 7 5
3  5 7 6
4  5 9 6
5  2 5 9
6  4 5 4
7  2 0 7
8  2 5 8
9  4 5 8
10 6 9 5
11 7 3 3
12 4 4 6
13 2 2 4
14 4 7 3
15 6 4 7
16 9 6 4
17 6 5 5
18 7 4 5
19 3 3 4
20 3 5 5

Adding suffix _1 to column names in df1 −

> colnames(df1)<-paste(colnames(df1),"1",sep="_")
> df1

Output

   x_1 y_1 z_1
1    6   3   2
2    9   7   5
3    5   7   6
4    5   9   6
5    2   5   9
6    4   5   4
7    2   0   7
8    2   5   8
9    4   5   8
10   6   9   5
11   7   3   3
12   4   4   6
13   2   2   4
14   4   7   3
15   6   4   7
16   9   6   4
17   6   5   5
18   7   4   5
19   3   3   4
20   3   5   5

Example2

Live Demo

> First<-rnorm(20)
> Second<-rnorm(20)
> df2<-data.frame(First,Second)
> df2

Output

         First     Second
1   1.00282455  0.5759739
2   0.35202536  1.3904835
3   0.41651858 -1.4070300
4  -1.07936487  1.0501346
5  -0.48215611 -0.9315004
6   0.01836988  0.4579780
7  -0.53021884 -0.9794603
8   0.07023623 -0.9540754
9  -0.82364958 -1.5772256
10 -0.41617725  0.5206476
11  0.18096607 -0.2642566
12  0.09188606 -1.1760547
13 -0.17121381 -1.7566332
14 -1.71346331 -0.1962034
15 -0.01604117 -1.2129497
16  0.16550767 -0.6901972
17  1.19758517 -1.3377314
18 -0.19054988  1.1551758
19  0.23210609 -0.8034687
20  1.17883619 -0.8621083

Adding suffix _Group to column names in df2 −

> colnames(df2)<-paste(colnames(df2),"Group",sep="_")
> df2

Output

   First_Group Second_Group
1   1.00282455    0.5759739
2   0.35202536    1.3904835
3   0.41651858   -1.4070300
4  -1.07936487    1.0501346
5  -0.48215611   -0.9315004
6   0.01836988    0.4579780
7  -0.53021884   -0.9794603
8   0.07023623   -0.9540754
9  -0.82364958   -1.5772256
10 -0.41617725    0.5206476
11  0.18096607   -0.2642566
12  0.09188606   -1.1760547
13 -0.17121381   -1.7566332
14 -1.71346331   -0.1962034
15 -0.01604117   -1.2129497
16  0.16550767   -0.6901972
17  1.19758517   -1.3377314
18 -0.19054988    1.1551758
19  0.23210609   -0.8034687
20  1.17883619   -0.8621083