Remove Element from a List in R

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There are the following methods to remove an element from a list in R.

Method 1: Remove an element from a list using a minus sign

The easiest way to remove an element from a list in R is to use a minus sign (-) or negative indexing. For example, you can remove the second element from the main_list using the main_list[–2] expression.

Example

main_list <- list("bmw", "audi", "benley", "mercedez")

main_list <- main_list[-3]

print(main_list)

Output

[[1]]
[1] "bmw"

[[2]]
[1] "audi"

[[3]]
[1] "mercedez"

You can see that we removed the third element from the list using negative indexing.

Method 2: Remove Element from List using NULL

You can set the element at a specific position to NULL to remove it from the list in R.

Example

[[1]]
[1] "bmw"

[[2]]
[1] "audi"

[[3]]
[1] "mercedez"

Output

[[1]]
[1] "bmw"

[[2]]
[1] "audi"

[[3]]
[1] "mercedez"

Method 3: Remove list element by Name with %in% Operator

The “%in%” operator returns a logical vector, which suggests whether a certain value of a data object exists in another element.

Example

main_list <- list(a = "bmw", b = "audi", c = "benley", d = "mercedez")

updated_list <- main_list[names(main_list) %in% "c" == FALSE]

updated_list

Output

$a
[1] "bmw"

$b
[1] "audi"

$d
[1] "mercedez"

Method 4: Using Filter and != operator

If you want to remove an element based on its value, you can use the filter() function.

Example

main_list <- list("bmw", "audi", "bentley", "mercedez")

main_list <- Filter(function(x) x != "bentley", main_list)

print(main_list)

Output

[[1]]
[1] "bmw"

[[2]]
[1] "audi"

[[3]]
[1] "mercedez"

Remember that this method will remove all occurrences of the specified value in the list.

Remove Multiple Elements from a List

You can remove multiple elements from a list in R by passing the vector containing the indices of the vector values.

Example

main_list <- list(a = "bmw", b = "audi", c = "benley", d = "mercedez")

updated_list <- main_list[-c(1, 3)]

updated_list

Output

$b
[1] "audi"

$d
[1] "mercedez"

You can also assign NULL to the indices vector to remove the list elements.

main_list <- list(a = "bmw", b = "audi", c = "benley", d = "mercedez")

updated_list <- main_list
updated_list[c(1, 3)] <- NULL
updated_list

Output

$b
[1] "audi"

$d
[1] "mercedez"

That’s it.

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