You can use the **mean()** function in R to calculate the mean of values in a vector:

mean(x)

The following examples show how to use this function in practice.

**Example 1: Calculate Mean of Vector**

The following code shows how to calculate the mean value of a vector in R:

#define vector x <- c(3, 6, 7, 7, 12, 14, 19, 22, 24) #calculate mean of vector mean(x) [1] 12.66667

If your vector has missing values, be sure to specify **na.rm = TRUE** to ignore missing values when calculating the mean:

#define vector with some missing values x <- c(3, 6, 7, 7, NA, 14, NA, 22, 24) #calculate mean of vector mean(x, na.rm = TRUE) [1] 11.85714

You can also use the **trim** argument to trim a certain fraction (0 to 0.5) of observations from each end of a vector before calculating the mean:

#define vector x <- c(3, 6, 7, 7, 12, 14, 19, 22, 24) #calculate mean of vector after trimming 20% of observations off each end mean(x, trim = 0.2) [1] 12.42857

**Example 2: Calculate Mean of Column in Data Frame**

The following code shows how to calculate the mean value of a certain column in a data frame:

#define data frame df <- data.frame(a=c(3, 6, 7, 7, 12, 14, 19, 22, 24), b=c(4, 4, 5, 12, 13, 14, 9, 1, 2), c=c(5, 6, 6, 3, 5, 5, 6, 19, 25)) #calculate mean of column 'a' mean(df$a) [1] 12.66667

**Example 3: Calculate Mean of Several Columns in Data Frame**

The following code shows how to use the **apply()** function to calculate the mean of several columns in a data frame:

#define data frame df <- data.frame(a=c(3, 6, 7, 7, 12, 14, 19, 22, 24), b=c(4, 4, 5, 12, 13, 14, 9, 1, 2), c=c(5, 6, 6, 3, 5, 5, 6, 19, 25)) #calculate mean of columns 'a' and 'c' apply(df[ , c('a', 'c')], 2, mean) a c 12.666667 8.888889

**Additional Resources**

How to Calculate the Mean by Group in R

How to Calculate a Weighted Mean in R

How to Calculate Geometric Mean in R