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 #define new vector with a different value in position 2
data_new #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 #define new vector with different values in position 1, 2, and 8
data_new #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 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 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