# Convert matrix to list in R

In this article, we will discuss how to convert a given matrix to a List in R Programming Language.

### Conversion of a matrix into a list in Column-major order

The as.list() is an inbuilt function that takes an R language object as an argument and converts the object into a list. We have used this function to convert our matrix to a list. These objects can be Vectors, Matrices, Factors, and data frames. By default, as.list() converts the matrix to a list of lists in column-major order.

Therefore, we have to use unlist() function** **to convert the list of lists to a single list. unlist() function in R Language is used to convert a list of lists to a single list, by preserving all the components.

**Syntax: **

unlist(as.list(matrix))

**Example:**

## R

`mat = ` `matrix` `(1:12,nrow=3, ncol=4)` ` ` `print` `(` `"Sample matrix:"` `)` `print` `(mat)` ` ` `print` `(` `"Matrix into a single list"` `)` `unlist` `(` `as.list` `(mat))` |

**Output:**

[1] “Sample matrix:”

[,1] [,2] [,3] [,4]

[1,] 1 4 7 10

[2,] 2 5 8 11

[3,] 3 6 9 12

[1] “Matrix into a single list”

[1] 1 2 3 4 5 6 7 8 9 10 11 12

### Conversion of a matrix into a list in Row-major order

For this approach we first have to find the transpose of the matrix In the code below, we have used t()** **function to calculate the transpose of our sample matrix. Due to which our matrix gets converted to a list in a Row-Major order.

The rest of the process is the same as above.

**Syntax: **

unlist( as.list( t(mat) ))

**Example:**

## R

`mat = ` `matrix` `(1:12,nrow=3, ncol=4)` ` ` `print` `(` `"Sample matrix:"` `)` `print` `(mat)` ` ` `print` `(` `"Result after conversion"` `)` `unlist` `(` `as.list` `(` `t` `(mat)))` |

**Output:**

[1] “Sample matrix:”

[,1] [,2] [,3] [,4]

[1,] 1 4 7 10

[2,] 2 5 8 11

[3,] 3 6 9 12

[1] “Result after conversion”

[1] 1 4 7 10 2 5 8 11 3 6 9 12