Why vectors are the fundamental data structure in R Programming - Challenge Your Understanding

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of vector recycling in R

What is the output of this R code snippet?

R Programming

x <- c(1, 2, 3)
y <- c(10, 20)
z <- x + y
print(z)

A [1] 11 22 13

B [1] 10 20 30

C [1] 11 12 13

D [1] 11 22 33

💡 Hint

Remember how R recycles shorter vectors to match the length of longer vectors.

In R, when you add two vectors of different lengths, the shorter one is recycled to match the longer one. Here, y = c(10, 20) is recycled to c(10, 20, 10). So, z = c(1+10, 2+20, 3+10) = c(11, 22, 13).

🧠 Conceptual

intermediate

Why vectors are fundamental in R

Which statement best explains why vectors are the fundamental data structure in R?

A Vectors provide a simple, consistent way to store and operate on sequences of data efficiently.

B Vectors allow storing multiple data types in a single object without coercion.

C Vectors are the only data structure that can hold named elements in R.

D Vectors automatically optimize memory usage by compressing data.

💡 Hint

Think about how R handles data and operations on collections of values.

Vectors are fundamental because they provide a simple and consistent way to store sequences of data of the same type and allow efficient vectorized operations, which is core to R's design.

🔧 Debug

advanced

Identify the error in vector subsetting

What error will this R code produce and why?

R Programming

v <- c(5, 10, 15)
print(v["2"])

A NULL

B [1] 10

C Error: invalid subscript type 'character'

D Error: subscript out of bounds

💡 Hint

Check the type of the index used for subsetting a vector.

In R, numeric vectors are indexed by numeric or logical values. Using a character string as an index without names causes an error.

📝 Syntax

advanced

Correct vector creation syntax

Which option correctly creates a numeric vector with elements 4, 5, and 6 in R?

A v <- vector(4, 5, 6)

B v <- c(4, 5, 6)

C v <- c[4, 5, 6]

D v <- (4, 5, 6)

💡 Hint

Remember the function used to combine elements into a vector.

The function c() combines values into a vector. Other options are either invalid syntax or incorrect function usage.

🚀 Application

expert

Vectorized operation result

Given the vectors a <- c(2, 4, 6) and b <- c(1, 3, 5), what is the result of the expression a * b + 1?

R Programming

a <- c(2, 4, 6)
b <- c(1, 3, 5)
result <- a * b + 1
print(result)

A [1] 3 13 31 0

B [1] 3 13 31 1

C [1] 3 13 31 7

D [1] 3 13 31

💡 Hint

Multiply element-wise then add 1 to each element.

Element-wise multiplication: (2*1, 4*3, 6*5) = (2, 12, 30). Adding 1 to each gives (3, 13, 31).