Vector recycling behavior in R Programming - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to create a vector that repeats the elements of c(1, 2) to length 6.

R Programming

rep(c(1, 2), [1] = 3)

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

Atimes

Beach

Clength.out

Drepeat

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'each' repeats each element individually, not the whole vector.

Using 'length.out' tries to set the total length, not the repeat count.

The times argument tells rep() how many times to repeat the whole vector.

2fill in blank

medium

Complete the code to add two vectors with different lengths using recycling.

R Programming

c(1, 2, 3, 4) + c(10, [1])

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

A20, 30, 40, 50

B20

C20, 30

D20, 30, 40

Attempts:

3 left

💡 Hint

Common Mistakes

Using a vector with length 1 does not show recycling clearly.

Using a vector longer than the first causes an error.

The shorter vector c(10, 20, 30) is recycled to match the length of the longer vector c(1, 2, 3, 4). Here, only 10, 20 are needed to fill the blank to make recycling happen.

3fill in blank

hard

Fix the error in the code that tries to add vectors of incompatible lengths.

R Programming

c(1, 2, 3) + c(10, 20, 30, [1])

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

A50

B40

C60

D70

Attempts:

3 left

💡 Hint

Common Mistakes

Adding vectors of lengths that are not multiples causes warnings.

Adding vectors of different lengths without recycling causes errors.

The second vector has length 4, which is not a multiple of 3, so recycling causes a warning. Removing the last element fixes the error.

4fill in blank

hard

Fill both blanks to create a vector that recycles elements of c(1, 2) to length 5 and then multiply by 2.

R Programming

rep(c(1, 2), [1] = 5) * [2]

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

Alength.out

Btimes

C2

Deach

Attempts:

3 left

💡 Hint

Common Mistakes

Using 'times' instead of 'length.out' changes repetition count, not length.

Multiplying by a vector instead of a number causes unexpected results.

length.out = 5 makes the vector length 5 by recycling, and multiplying by 2 doubles each element.

5fill in blank

hard

Fill all three blanks to create a named vector with lengths of words longer than 3 letters.

R Programming

lengths = { [1]: [2] for word in words if nchar(word) [3] 3 }

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

Aword

Bnchar(word)

C>

D<

Attempts:

3 left

💡 Hint

Common Mistakes

Using '<' instead of '>' filters the wrong words.

Swapping names and values causes incorrect vector structure.

This creates a named vector where names are words and values are their lengths, but only for words longer than 3 letters.