sub and gsub in R Programming - Interactive Code Practice

Practice - 5 Tasks

1fill in blank

easy

Complete the code to replace the first occurrence of 'cat' with 'dog' in the string.

R Programming

result <- sub([1], "dog", "cat and cat")

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

A"cat"

B"dog"

C"and"

D"cat and cat"

Attempts:

3 left

💡 Hint

Common Mistakes

Using the replacement string as the pattern.

Using the whole string as the pattern.

The sub function replaces the first match of the pattern, so we use "cat" as the pattern to replace.

2fill in blank

medium

Complete the code to replace all occurrences of 'cat' with 'dog' in the string.

R Programming

result <- gsub([1], "dog", "cat and cat")

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

A"cat"

B"dog"

C"and"

D"cat and cat"

Attempts:

3 left

💡 Hint

Common Mistakes

Using sub instead of gsub for all replacements.

Using the replacement string as the pattern.

The gsub function replaces all matches of the pattern, so the pattern should be "cat" to replace all occurrences.

3fill in blank

hard

Fix the error in the code to replace the first 'a' with 'o' in the string.

R Programming

result <- sub([1], "o", "banana")

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

Aa

B"a"

C'a'

Dbanana

Attempts:

3 left

💡 Hint

Common Mistakes

Using unquoted letters as patterns.

Using the whole string as the pattern.

The pattern must be a string, so it needs to be in quotes like "a".

4fill in blank

hard

Fill both blanks to replace all digits with '#' in the string.

R Programming

result <- gsub([1], [2], "Phone: [phone]")

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

A"[0-9]"

B"#"

C"-"

D"Phone"

Attempts:

3 left

💡 Hint

Common Mistakes

Using sub instead of gsub to replace all digits.

Using wrong pattern that doesn't match digits.

The pattern "[0-9]" matches any digit, and "#" is the replacement character.

5fill in blank

hard

Fill all three blanks to replace all vowels with '*' in the string.

R Programming

result <- gsub([1], [2], [3])

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

A"[aeiouAEIOU]"

B"*"

C"Hello World"

D"[0-9]"

Attempts:

3 left

💡 Hint

Common Mistakes

Using wrong pattern that doesn't match vowels.

Using sub instead of gsub to replace all vowels.

The pattern "[aeiouAEIOU]" matches all vowels, "*" is the replacement, and "Hello World" is the input string.