How to loop through items in List in R?

R – Loop through items in List

To loop through items in a list in R programming, use For Loop.

In this tutorial, we will learn how to iterate over a list using For Loop, with the help of example programs.

The syntax to use For Loop for a list is

for (item in list) {
    //code
}

We can access i^th item inside for-loop, during i^th iteration.

Examples

In the following program, we will create a list with some initial values, and iterate over the items of the list using for loop.

example.R

myList <- list("Sunday", "Monday", "Tuesday")

for (item in myList) {
    print(item)
}

Output

[1] "Sunday"
[1] "Monday"
[1] "Tuesday"

Now, let us take a list of numbers, and iterate over them using For Loop.

example.R

myList <- list(1, 4, 9, 16, 25)

for (item in myList) {
    print(item)
}

Output

[1] 1
[1] 4
[1] 9
[1] 16
[1] 25

Conclusion

In this R Tutorial, we learned how to iterate over items in a list in R programming using For Loop, with the help of examples.