The **replace()** function in R can be used to replace specific elements in a vector with new values.

This function uses the following syntax:

**replace(x, list, values)**

where:

**x**: Name of vector**list**: Elements to replace**values**: Replacement values

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

**Example 1: Replace One Value in Vector**

The following code shows how to replace the element in position 2 of a vector with a new value of 50:

#define vector of values data <- c(3, 6, 8, 12, 14, 15, 16, 19, 22) #define new vector with a different value in position 2 data_new <- replace(data, 2, 50) #view new vector data_new [1] 3 50 8 12 14 15 16 19 22

Notice that the element in position 2 has changed, but every other value in the original vector remained the same.

**Example 2: ****Replace Multiple Values in Vector**

The following code shows how to replace the values of multiple elements in a vector with new values:

#define vector of values data <- c(2, 4, 6, 8, 10, 12, 14, 16) #define new vector with different values in position 1, 2, and 8 data_new <- replace(data, c(1, 2, 8), c(50, 100, 200)) #view new vector data_new [1] 50 100 6 8 10 12 14 200

Notice that the elements in position 1, 2, and 8 all changed.

**Example 3: ****Replace Values in Data Frame**

The following code shows how to replace the values in a certain column of a data frame that meet a specific condition:

#define data frame df <- data.frame(x=c(1, 2, 4, 4, 5, 7), y=c(6, 6, 8, 8, 10, 11)) #view data frame df x y 1 1 6 2 2 6 3 4 8 4 4 8 5 5 10 6 7 11 #replace values in column 'x' greater than 4 with a new value of 50 df$x <- replace(df$x, df$x > 4, 50) #view updated data frame df x y 1 1 6 2 2 6 3 4 8 4 4 8 5 50 10 6 50 11

Each value in column ‘x’ that was greater than 4 was replaced with a value of 50.

All other values in the data frame remained the same.

**Additional Resources**

The following tutorials explain how to use other common functions in R:

How to Use tabulate() Function in R

How to Use split() Function in R

How to Use match() Function in R

How to Use replicate() Function in R