How to access the items of a list in R
Onyejiaku Theophilus ChidaluOverview
A list in R is simply a collection of ordered or changeable data.
The list items are combined together using the list() function. This function takes the items we want in our list as its parameter.
Now, let’s create a list.
Code example
# Vector of strings
my_list1 <- list("pear", "cherry", "lemon")
# vector of numbers
my_list2 <- c(1, 2, 3, 4, 5)
# Printing the vectors
my_list1
my_list2Code explanation
-
Line 2: We create a list
my_list1containing string values or items. -
Line 5: We create another list
my_list2containing numerical values or items. -
Lines 8-9: We print the two lists we created.
How to access the items of a list
To access the items of a list, we simply refer to its index number inside brackets []. In R, the first list item has its index as 1, the second item has its index as 2, and so on.
In the code below, we want to access the items of a list.
Code example
# creating a list
my_list <- list("pear", "cherry", "lemon")
# accessing the first item of the list
my_list[1]
# accessing the second item of the list
my_list[2]Code explanation
We can see that we were able to access the items of the vector my_vector by simply referring to the index number of the specific item inside brackets [].
RELATED TAGS
CONTRIBUTOR
Onyejiaku Theophilus ChidaluView all Courses
