Select second element of a Given Nested list in R Programming

Last update on December 21 2024 10:11:29 (UTC/GMT +8 hours)

Write a R program to select second element of a given nested list.

Sample Solution:

R Programming Code :

# Create a nested list with three sublists, each containing two elements
x = list(list(0,2), list(3,4), list(5,6))

# Print a message indicating the following output is the original nested list
print("Original nested list:")

# Print the original nested list
print(x)

# Extract the second element from each sublist using lapply and the '[[', 2 function
e = lapply(x, '[[', 2)

# Print a message indicating the following output is the second element of each sublist
print("Second element of the nested list:")

# Print the extracted second elements from each sublist
print(e)

Output:

[1] "Original nested list:"
[[1]]
[[1]][[1]]
[1] 0

[[1]][[2]]
[1] 2


[[2]]
[[2]][[1]]
[1] 3

[[2]][[2]]
[1] 4


[[3]]
[[3]][[1]]
[1] 5

[[3]][[2]]
[1] 6


[1] "Second element of the nested list:"
[[1]]
[1] 2

[[2]]
[1] 4

[[3]]
[1] 6                         

Explanation:

• Create Nested List:
  x = list(list(0,2), list(3,4), list(5,6))
• Creates a nested list x with three sublists. Each sublist contains two numbers.
• Print Original Nested List:
  print("Original nested list:")
  print(x)
• Prints the message "Original nested list:" followed by the nested list x.
• Extract Second Elements:
  e = lapply(x, '[[', 2)
• Uses lapply to apply the extraction function [[ to each sublist in x, retrieving the second element from each sublist. The results are stored in e.
• Print Extracted Second Elements:
  print("Second element of the nested list:")
  print(e)
• Prints the message "Second element of the nested list:" followed by the extracted second elements stored in e.

R Programming Code Editor:

Have another way to solve this solution? Contribute your code (and comments) through Disqus.

Previous: Write a R program to create a list containing a vector, a matrix and a list and add element at the end of the list.
Next: Write a R program to create a list containing a vector, a matrix and a list and remove the second element.