To **calculate** an **Average** in **R**, you can use the **mean()** function. It takes a numeric vector, list, or data frame column as an argument and returns the sum of its values divided by their number. For example, **mean(c(1, 2, 3, 4))** returns **2.5**.

The mathematical formula for calculating the average is the following.

The **mean()** is a built-in function that accepts numeric vector and boolean value and returns the average of that vector. The Mean is the sum of its data values divided by the data count.

While calculating an average, if the vector contains **NA** **values**, they are excluded from the calculation.

**Syntax**

`mean(x, na.rm)`

**Parameters**

**x:** The **x** is a Numeric Vector.

**na.rm: **It is a boolean value to ignore the NA value.

**Example 1: Simple program that calculates the average of a vector**

```
rv <- c(11, 21, 19, 18, 51, 51, 71)
# Calculating average using mean()
mean(rv)
```

**Output**

`[1] 34.57143`

We defined a vector using the c() function and the mean() function to calculate the average of the vector, which is **34.57143.**

**Alternate approaches**

**Method 2: Using sum() and length() function to calculate the average**

To calculate the average, divide the sum of the vector by the number of elements in the vector. Use the **sum()** function to calculate the sum of a vector of numbers and the **length()** function to calculate the number of elements in a vector.

**Example**

```
vector <- c(10, 20, 30, 40, 50)
average <- sum(vector) / length(vector)
print(average)
```

**Output**

`[1] 30`

**Method 3: Using the aggregate() function to calculate the average**

The **aggregate()** function in R can be used to calculate the average. It accepts an R object like a **data** **frame**, **grouping** **variable**, and **FUN** which we will use the **mean()** function.

**Example**

```
df <- data.frame(a1 = 1:3, a2 = 4:6, a3 = 7:9)
aggregate(df, list(df$a2), mean)
```

**Output**

```
Group.1 a1 a2 a3
1 4 1 4 7
2 5 2 5 8
3 6 3 6 9
```

**FAQ**

**What is the difference between the mean and average in R**

The term **“average”** refers to a specific mean type, such as the **median** or **mode**. In R, the mean() function calculates the arithmetic mean of a set of numbers.

**How to calculate the average of a variable in R?**

Use the **mean()** function to calculate the average of a variable in R. Alternate ways are using the **sum() **along with the **length()** function and using the **aggregate()** function.

**How to calculate the average of a variable grouped by another variable in R?**

Use the **aggregate()** function to calculate the average of a variable grouped by another variable.

The basic syntax is **aggregate(x ~ group, data, mean)**, where x is the variable, the group is the variable to groupby, and data is either a **data frame** or **matrix**.

**Conclusion**

In this tutorial, we have seen how to calculate the average of a **Vector**, **List**, and **data frame** in **R** using **mean()**, **sum()** along with **length()**, **aggregate()**, **lapply()**, and **sapply()** methods.

If you have a data set of numerical values, use the **mean()** function to calculate an average.

That is it.

**Further reading**

How to Calculate the Average of List in R

How to Calculate the Average of a data frame in R

Krunal Lathiya is a Software Engineer with over eight years of experience. He has developed a strong foundation in computer science principles and a passion for problem-solving. In addition, Krunal has excellent knowledge of Data Science and Machine Learning, and he is an expert in R Language.