`rep()`

is a built-in R function that replicates the values in the provided vector. This tutorial shows how to use `rep()`

function in R with 4 examples.

## Example 1

The following code is to repeat the number 4 twice.

```
# repeat the number 4 twice
rep(4, 2)
```

Output:

[1] 4 4

## Example 2

```
# repeat 4 times of the number from 1 to 3
rep(1:3, 4)
```

Output:

[1] 1 2 3 1 2 3 1 2 3 1 2 3

## Example 3

You can also add the parameter of `length.ou`

t to restrict the length of the output. The following is the example.

```
# add the restriction of length = 5 to the function
rep(1:3, 4, length.out=5)
```

Output:

[1] 1 2 3 1 2

## Example 4

You can also the `each`

parameter in `rep()`

to repeat the elements of x each time.

```
# add each = 3 to repeat the elements in the X (i.e., 1:2)
rep(1:2, 4, each=3)
```

Output:

[1] 1 1 1 2 2 2 1 1 1 2 2 2 1 1 1 2 2 2 1 1 1 2 2 2