How to add a new column to a matrix in R?
A data collection process is one of the initial and very important tasks in a data analysis project and sometimes we miss something. Therefore, we need to collect that data later and add it to the originally collected data. This mistake can be done for matrix data as well, hence we might need to add a new column to original matrix and this can be done by using cbind function.
Example1
Live Demo
> M1<-matrix(1:25,nrow=5)
> M1
Output
[,1] [,2] [,3] [,4] [,5]
[1,] 1 6 11 16 21
[2,] 2 7 12 17 22
[3,] 3 8 13 18 23
[4,] 4 9 14 19 24
[5,] 5 10 15 20 25
Example
> V1<-26:30
> M1<-cbind(M1,V1)
> M1
Output
V1
[1,] 1 6 11 16 21 26
[2,] 2 7 12 17 22 27
[3,] 3 8 13 18 23 28
[4,] 4 9 14 19 24 29
[5,] 5 10 15 20 25 30
Example2
Live Demo
> M2<-matrix(rpois(81,5),ncol=9)
> M2
Output
[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8] [,9]
[1,] 7 3 3 4 2 3 6 3 6
[2,] 7 5 6 6 4 4 4 5 3
[3,] 5 6 3 9 4 3 4 6 4
[4,] 4 4 3 6 1 3 6 9 4
[5,] 2 4 4 5 9 2 3 4 4
[6,] 6 5 5 3 3 4 3 9 5
[7,] 11 5 5 6 4 5 3 4 4
[8,] 4 3 1 1 9 3 5 4 3
[9,] 14 7 5 1 6 4 4 6 5
Example
> V2<-rpois(9,10)
> M2<-cbind(M2,V2)
> M2
Output
V2
[1,] 7 3 3 4 2 3 6 3 6 14
[2,] 7 5 6 6 4 4 4 5 3 9
[3,] 5 6 3 9 4 3 4 6 4 7
[4,] 4 4 3 6 1 3 6 9 4 10
[5,] 2 4 4 5 9 2 3 4 4 6
[6,] 6 5 5 3 3 4 3 9 5 11
[7,] 11 5 5 6 4 5 3 4 4 10
[8,] 4 3 1 1 9 3 5 4 3 12
[9,] 14 7 5 1 6 4 4 6 5 13
Example3
Live Demo
> M3<-matrix(rnorm(25,2,0.36),nrow=5)
> M3
Output
[,1] [,2] [,3] [,4] [,5]
[1,] 1.696484 1.269688 1.607353 1.913940 2.463333
[2,] 2.485409 2.107897 1.989745 2.072183 1.120741
[3,] 2.202257 1.715435 2.027664 1.230764 2.435480
[4,] 1.845053 2.132015 1.845209 1.480105 1.870550
[5,] 2.286963 1.776010 1.691820 1.634944 2.091766
Example
> V3<-rnorm(5,5,1)
> M3<-cbind(M3,V3)
> M3
Output
V3
[1,] 1.696484 1.269688 1.607353 1.913940 2.463333 4.961799
[2,] 2.485409 2.107897 1.989745 2.072183 1.120741 5.243562
[3,] 2.202257 1.715435 2.027664 1.230764 2.435480 4.393539
[4,] 1.845053 2.132015 1.845209 1.480105 1.870550 6.008758
[5,] 2.286963 1.776010 1.691820 1.634944 2.091766 5.988232
Example4
Live Demo
> M4<-matrix(round(runif(64,2,5),0),ncol=8)
> M4
Output
[,1] [,2] [,3] [,4] [,5] [,6] [,7] [,8]
[1,] 3 5 5 3 4 3 4 3
[2,] 3 3 4 3 3 3 4 3
[3,] 3 4 3 4 4 4 4 2
[4,] 3 2 3 2 5 2 5 4
[5,] 4 4 2 5 3 3 2 3
[6,] 3 4 3 3 4 2 4 5
[7,] 4 3 3 3 4 4 3 2
[8,] 4 3 4 3 4 4 2 5
Example
> V4<-round(runif(8,1,5),0)
> M4<-cbind(M4,V4)
> M4
Output
V4
[1,] 3 5 5 3 4 3 4 3 5
[2,] 3 3 4 3 3 3 4 3 5
[3,] 3 4 3 4 4 4 4 2 4
[4,] 3 2 3 2 5 2 5 4 2
[5,] 4 4 2 5 3 3 2 3 5
[6,] 3 4 3 3 4 2 4 5 4
[7,] 4 3 3 3 4 4 3 2 2
[8,] 4 3 4 3 4 4 2 5 3
Example5
Live Demo
> M5<-matrix(round(rexp(36,1.22),2),ncol=6)
> M5
Output
[,1] [,2] [,3] [,4] [,5] [,6]
[1,] 1.55 0.02 1.27 0.31 0.10 0.08
[2,] 1.13 0.26 0.46 0.06 0.90 0.43
[3,] 0.14 1.26 0.89 0.12 0.16 0.63
[4,] 0.33 0.79 1.03 2.72 0.17 0.49
[5,] 0.17 4.59 0.04 0.26 0.18 1.52
[6,] 0.46 1.05 0.10 0.96 0.64 0.31
Example
> V5<-round(rexp(6,2.1),2)
> M5<-cbind(M5,V5)
> M5
Output
V5
[1,] 1.55 0.02 1.27 0.31 0.10 0.08 0.07
[2,] 1.13 0.26 0.46 0.06 0.90 0.43 0.00
[3,] 0.14 1.26 0.89 0.12 0.16 0.63 0.40
[4,] 0.33 0.79 1.03 2.72 0.17 0.49 0.23
[5,] 0.17 4.59 0.04 0.26 0.18 1.52 0.32
[6,] 0.46 1.05 0.10 0.96 0.64 0.31 0.64
Published on 19-Nov-2020 12:16:06
