Empty vectors in R are the vectors whose length is zero. There are several ways to create empty vectors and then add elements to them. Vector is a basic data structure that contains elements of the same type. Let’s see how to create or initialize the empty vector in R.

**How to Create an Empty Vector in R**

There are the following ways to create an empty vector.

- Using vector() method
- Using c() method
- Using numeric() method
- Using rep() method
- Assigning NULL to an existing vector.

**Create an empty Vector using the vector() method**

To create an empty vector in R, use the basic vector() method, and don’t pass any parameter. By default, it will create an empty vector.

```
rv <- vector()
rv
```

**Output**

`logical(0)`

To check the length of the vector, use the length() method.

```
rv <- vector()
length(rv)
```

**Output**

`[1] 0`

The length() method will return the length of the vector object passed in the argument.

Now, you can add elements to the vector.

```
rv <- vector()
length(rv)
cat("After adding elements to an empty vector", "\n")
rv <- c(1:7)
rv
length(rv)
```

**Output**

```
[1] 0
After adding elements to an empty vector
[1] 1 2 3 4 5 6 7
[1] 7
```

And you can see from the output that we have added the elements to the vector.

**Using the c() method to create an empty Vector**

The c() method is mainly used for creating a vector in R. We can also use the c() method to empty the vector.

```
rv <- c()
rv
cat("length of rv : ", length(rv), "\n")
is.null(rv)
```

**Output**

```
NULL
length of rv : 0
[1] TRUE
```

As you can see, we created an empty vector using the c() function.

**Using numeric() function**

The numeric() function in R creates a double-precision vector of the length specified in the argument with all values zero.

So, we will create a vector with 0 length using the numeric() function.

```
rv <- numeric(0)
rv
cat("length of rv : ", length(rv), "\n")
```

**Output**

```
numeric(0)
length of rv : 0
```

**Using rep( ) function**

The rep() function replicates the values in the input data. It is a generic function.

```
rv <- rep(NULL, 0)
rv
cat("length of rv : ", length(rv), "\n")
```

**Output**

```
NULL
length of rv : 0
```

Here, you can use the is.null() function to check if the vector is **NULL** or not. The is.null() function returns a boolean vector that is either **TRUE** or **FALSE**.

You can also create an empty vector with the rep() function and **NA. **The “**NA**” in R designates a missing value, also known as Not Available.

```
rv <- rep(NA, 0)
rv
length(rv)
is.null(rv)
```

**Output**

```
logical(0)
[1] 0
[1] FALSE
```

As you can see that the rep() function with NA returns an empty vector, but it has not NULL value.

**Assigning NULL to an existing vector**

If you assign any vector to a NULL value, then that existing vector will become empty of NULL type.

```
rv <- 1:5
rv
length(rv)
rv <- NULL
rv
length(rv)
is.null(rv)
```

**Output**

```
[1] 1 2 3 4 5
[1] 5
NULL
[1] 0
[1] TRUE
```

First, we initialized a vector with five elements and then assign the **NULL** value to empty the vector of type **NULL**.

**Conclusion**

We have seen many ways to create an empty vector, and based on your requirements, and you can use one of the above approaches. You can use the **c()** function, **vector()** method, **rep()** or assign a **NULL** value to the existing vector or initialize the vector with **NULL**.