How to add columns with square of each column in R data frame?

To add columns with square of each column in R data frame, we can use setNames function and cbind function for squaring each value. This might be required when we want to use squared form of variables in the data analysis.

Check out the below given examples to understand how it can be done.

Example 1

Following snippet creates a sample data frame −

x1<-rpois(20,2)
x2<-rpois(20,5)
x3<-rpois(20,1)
df1<-data.frame(x1,x2,x3)
df1

Output

The following dataframe is created −

   x1 x2 x3
1  2  7  1
2  3  6  1
3  4  5  2
4  1  2  0
5  0  6  0
6  2  3  1
7  1  4  2
8  2  4  1
9  1  3  0
10 2  3  1
11 1  5  2
12 3  3  1
13 3  4  0
14 1  7  1
15 3  3  3
16 2  5  0
17 2  8  2
18 0  5  3
19 6  1  0
20 4  4  3

To add squared columns in df1, add the following code to the above snippet −

x1<-rpois(20,2)
x2<-rpois(20,5)
x3<-rpois(20,1)
df1<-data.frame(x1,x2,x3)
setNames(as.data.frame(cbind(df1,df1^2)), c(names(df1),paste0(names(df1),'_2')))

Output

If you execute all the above given codes as a single program, it generates the following output −

   x1 x2 x3 x1_2 x2_2 x3_2
1  2  7  1   4   49   1
2  3  6  1   9   36   1
3  4  5  2  16   25   4
4  1  2  0   1    4   0
5  0  6  0   0   36   0
6  2  3  1   4    9   1
7  1  4  2   1   16   4
8  2  4  1   4   16   1
9  1  3  0   1    9   0
10 2  3  1   4    9   1
11 1  5  2   1   25   4
12 3  3  1   9    9   1
13 3  4  0   9   16   0
14 1  7  1   1   49   1
15 3  3  3   9    9   9
16 2  5  0   4   25   0
17 2  8  2   4   64   4
18 0  5  3   0   25   9
19 6  1  0  36    1   0
20 4  4  3  16   16   9

Example 2

Following snippet creates a sample data frame −

y1<-round(rnorm(20),2)
y2<-round(rnorm(20),2)
df2<-data.frame(y1,y2)
df2

Output

The following dataframe is created −

     y1     y2
1  -0.05   0.98
2  -1.54  -1.98
3   0.66   0.61
4  -0.54   1.22
5   0.34  -0.70
6  -0.26   0.84
7   0.19  -0.20
8   1.39   1.11
9  -1.11  -0.61
10  0.88  -0.10
11 -0.74  -0.03
12 -1.35  -0.94
13  0.99  -1.93
14  1.56  -2.36
15 -0.36   0.95
16  0.38   0.69
17 -0.07  -0.95
18 -0.28   0.68
19 -1.10   0.82
20  0.41  -0.27

To add squared columns in df2, add the following code to the above snippet −

y1<-round(rnorm(20),2)
y2<-round(rnorm(20),2)
df2<-data.frame(y1,y2)
setNames(as.data.frame(cbind(df2,df2^2)), c(names(df2),paste0(names(df2),'_2')))

Output

If you execute all the above given codes as a single program, it generates the following output −

     y1    y2     y1_2     y2_2
1  -0.05   0.98   0.0025  0.9604
2  -1.54  -1.98   2.3716  3.9204
3   0.66   0.61   0.4356  0.3721
4  -0.54   1.22   0.2916  1.4884
5   0.34  -0.70   0.1156  0.4900
6  -0.26   0.84   0.0676  0.7056
7   0.19  -0.20   0.0361  0.0400
8   1.39   1.11   1.9321  1.2321
9  -1.11  -0.61   1.2321  0.3721
10  0.88  -0.10   0.7744  0.0100
11 -0.74  -0.03   0.5476  0.0009
12 -1.35  -0.94   1.8225  0.8836
13  0.99  -1.93   0.9801  3.7249
14  1.56  -2.36   2.4336  5.5696
15 -0.36   0.95   0.1296  0.9025
16  0.38   0.69   0.1444  0.4761
17 -0.07  -0.95   0.0049  0.9025
18 -0.28   0.68   0.0784  0.4624
19 -1.10   0.82   1.2100  0.6724
20  0.41  -0.27   0.1681  0.0729