Numeric and character vectors in R Programming - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of combining numeric and character vectors

What is the output of this R code when combining numeric and character vectors?

R Programming

v1 <- c(1, 2, 3)
v2 <- c("a", "b", "c")
v3 <- c(v1, v2)
print(v3)

A [1] "1" "2" "3" "a" "b" "c"

B [1] 1 2 3 "a" "b" "c"

C [1] 1 2 3 NA NA NA

D [1] 1 2 3 4 5 6

💡 Hint

Remember that combining numeric and character vectors converts all elements to characters.

When you combine numeric and character vectors in R, all elements are coerced to character type. So the numeric values become strings.

❓ Predict Output

intermediate

Length of a mixed vector

What is the length of the vector created by this code?

R Programming

v1 <- c(10, 20, 30)
v2 <- c("x", "y")
v3 <- c(v1, v2)
length(v3)

A NA

B 3

C 2

D 5

💡 Hint

The length counts all elements after combining.

The vector v3 combines 3 numeric and 2 character elements, so length is 5.

🔧 Debug

advanced

Error in vector creation with mixed types

What error does this R code produce?

R Programming

v <- c(1, "two", TRUE, 4.5)
print(v)

A No error; prints a character vector: "1" "two" "TRUE" "4.5"

B Error: unexpected string constant

C Error: cannot combine numeric and logical values

D No error; prints a numeric vector: 1 0 1 4.5

💡 Hint

Check how R coerces different types in a vector.

R coerces all elements to the most flexible type, here character, so no error occurs.

🧠 Conceptual

advanced

Understanding vector coercion priority

Which type will the vector have after combining these elements: numeric, logical, and character?

A Numeric

B Character

C Logical

D Factor

💡 Hint

R coerces to the most flexible type to hold all values.

Character is the most flexible type among logical, numeric, and character, so all elements become characters.

❓ Predict Output

expert

Output of vector recycling in arithmetic

What is the output of this R code?

R Programming

v1 <- c(1, 2, 3, 4)
v2 <- c(10, 20)
v3 <- v1 + v2
print(v3)

A Error: vectors must be the same length

B [1] 11 22 31 42

C [1] 11 22 13 24

D [1] 11 22 11 22

💡 Hint

Remember how R recycles shorter vectors in arithmetic operations.

v2 is recycled to match length of v1: (10,20,10,20). Adding element-wise gives (11,22,13,24).