Negative indexing for exclusion in R Programming - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to exclude the second element from the vector.

R Programming

vec <- c(10, 20, 30, 40)
result <- vec[[1]]
print(result)

Drag options to blanks, or click blank then click option'

A-2

B2

C-1

Dc(2)

Attempts:

3 left

💡 Hint

Common Mistakes

Using positive index includes the element instead of excluding it.

Using -2 excludes the second element from the vector.

2fill in blank

medium

Complete the code to exclude the first and third elements from the vector.

R Programming

vec <- c(5, 15, 25, 35)
result <- vec[[1]]
print(result)

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A-c(1, 3)

Bc(1, 3)

C-c(2, 4)

Dc(2, 4)

Attempts:

3 left

💡 Hint

Common Mistakes

Using positive indices includes those elements instead of excluding them.

Using -c(1, 3) excludes the first and third elements from the vector.

3fill in blank

hard

Fix the error in the code to exclude the last element from the vector.

R Programming

vec <- c(2, 4, 6, 8)
result <- vec[[1]]
print(result)

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Ac(length(vec))

Blength(vec)

C-length(vec)

D-1

Attempts:

3 left

💡 Hint

Common Mistakes

Using positive length(vec) includes only the last element instead of excluding it.

Using -length(vec) excludes the last element by negative indexing with the vector length.

4fill in blank

hard

Fill both blanks to exclude the second and fourth elements from the vector.

R Programming

vec <- c(3, 6, 9, 12, 15)
result <- vec[[1]([2])]
print(result)

Drag options to blanks, or click blank then click option'

A-c

Bc

C2, 4

D1, 3

Attempts:

3 left

💡 Hint

Common Mistakes

Using positive indices includes elements instead of excluding them.

Using -c(2, 4) excludes the second and fourth elements from the vector.

5fill in blank

hard

Fill all three blanks to exclude the first, third, and fifth elements from the vector.

R Programming

vec <- c(7, 14, 21, 28, 35, 42)
result <- vec[[1]([2])]
print(result)

# The excluded elements are [3].

Drag options to blanks, or click blank then click option'

A-c

Bc

C1, 3, 5

D7, 21, 35

Attempts:

3 left

💡 Hint

Common Mistakes

Using positive indices includes elements instead of excluding them.

Using -c(1, 3, 5) excludes the first, third, and fifth elements, which are 7, 21, and 35.