# R – Get Element by Index in a Vector

Vectors are a common data structure in R. We generally use vectors to store a sequence of values of the same type. In this tutorial, we will look at how to get an element by its index in a vector in R with the help of some examples.

## How to get an element by index in a vector?

Elements in a vector are indexed starting from 1. Use the `[]` notation to get a vector element by its index in R. The following is the syntax –

```# get element at index i in a vector
vec[i]```

It returns the element present in the vector at the ith index.

## Examples

Let’s look at some examples of extracting elements using their respective index in R. First, we will create a vector that we will be using throughout this tutorial.

```# create a vector
vec <- c(10, 20, 30, 40, 50)
# display the vector
print(vec)```

Output:

`[1] 10 20 30 40 50`

### Get the value at an index in a vector

Let’s use the above syntax to get the value at the index 2 in the `vec` vector.

```# get element in vector at index 2
print(vec[2])```

Output:

`[1] 20`

We get `20` as the output, which is the value at the second index in the vector, `vec`. Let’s now look at some more specific use-cases.

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### Get the first element in a vector

Let’s get the first value in the above vector. We know that a vector is indexed starting from 1 in R. So, the first value is present at index 1. Let’s use the above syntax to get the first value.

```# get the first element in the vector
print(vec[1])```

Output:

`[1] 10`

We get the first value in the above vector as `10`.

### Get the last element in a vector

You can similarly get the last value in a vector. The last value will present at the index which is equal to the length of the vector. You can use the `length()` function in R to get the length of a vector.

```# get the last element in the vector
print(vec[length(vec)])```

Output:

`[1] 50`

Here, we first use the `length()` function to find the length of the vector (which is the same as the index of the last element) and then use the `[]` notation to get the value at that index. We get `50` as the last element in the above vector.

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