# What is the difference between creating a matrix by using matrix function or as.matrix function in R?

R ProgrammingServer Side ProgrammingProgramming

The difference between as.matrix and matrix function is that nrow argument or ncol argument are not helpful with as.matrix function but with matrix function we can use them. Therefore, we can actual define a matrix with matrix function but if we have a data frame or data table then it can be converted to matrix by using as.matrix function.

Examples of creating matrix with as.matrix and matrix function

## Example1

Live Demo

M<−as.matrix(1:25,nrow=5)
M

## Output

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

## Example2

Live Demo

M<−as.matrix(1:25,ncol=5)
M

## Output

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

## Example3

Live Demo

M<−matrix(1:25,ncol=5)
M

## 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

## Example4

Live Demo

M<−matrix(1:25,nrow=5)
M

## 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

## Example5

Live Demo

M<−matrix(1:25,nrow=5,byrow=TRUE)
M

## Output

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

## Example6

Live Demo

M<−matrix(1:25,nrow=5,byrow=FALSE)
M

## 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
Published on 06-Nov-2020 13:53:43