R Programming - Count Number of Objects in a given list

R Programming: List Exercise-11 with Solution

Write a R program to count number of objects in a given list.

Sample Solution :

R Programming Code :

# Create a list with various elements: a vector, a matrix, and another list
list_data <- list(c("Red", "Green", "Black"), matrix(c(1, 3, 5, 7, 9, 11), nrow = 2),
                  list("Python", "PHP", "Java"))

# Print a message indicating that the following output is the list
print("List:")

# Print the content of the list
print(list_data)

# Print a message indicating that the following output is the number of objects in the list
print("Number of objects in the said list:")

# Calculate and print the number of objects (elements) in the list
length(list_data)

Output:

[1] "List:"
[[1]]
[1] "Red"   "Green" "Black"

[[2]]
     [,1] [,2] [,3]
[1,]    1    5    9
[2,]    3    7   11

[[3]]
[[3]][[1]]
[1] "Python"

[[3]][[2]]
[1] "PHP"

[[3]][[3]]
[1] "Java"


[1] "Number of objects in the said list:"
[1] 3                         

Explanation:

• Create a list:
• list_data <- list(c("Red", "Green", "Black"), matrix(c(1, 3, 5, 7, 9, 11), nrow = 2), list("Python", "PHP", "Java"))
• This line creates a list named list_data containing:
• A vector with three strings: "Red", "Green", "Black"
• A matrix with the numbers 1, 3, 5, 7, 9, 11 arranged in 2 rows
• Another list with three strings: "Python", "PHP", "Java"
• Print the label for the list:
• print("List:")
• This line prints the label "List:" to indicate that the following output will display the contents of list_data.
• Print the list:
• print(list_data)
• This line prints the actual contents of list_data.
• Print the label for the number of objects:
• print("Number of objects in the said list:")
• This line prints the label "Number of objects in the said list:" to indicate that the following output will show the count of items in list_data.
• Print the number of objects in the list:
• length(list_data)
• This line calculates and prints the number of objects (elements) in list_data, which is 3 in this case.

R Programming Code Editor:

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