R Console and script files in R Programming - Practice Problems & Coding Challenges

Challenge - 5 Problems

❓ Predict Output

intermediate

Output of variable assignment in R Console

What will be the output in the R console after running this code?

R Programming

x <- 5
x + 3

A Error: object 'x' not found

B [1] 53

C [1] 15

D [1] 8

💡 Hint

Remember that '<-' assigns a value to a variable and '+' adds numbers.

The variable x is assigned the value 5. Then x + 3 calculates 5 + 3, which is 8, printed as [1] 8 in R console.

❓ Predict Output

intermediate

Output of sourcing an R script file

Given an R script file named 'script.R' containing: my_var <- 10 print(my_var * 2) What will be printed in the R console after running source('script.R')?

R Programming

my_var <- 10
print(my_var * 2)

A Error: object 'my_var' not found

B [1] 20

C [1] 10

D NULL

💡 Hint

The print function outputs the value to the console.

The script assigns 10 to my_var and prints my_var * 2, which is 20, so the console shows [1] 20.

❓ Predict Output

advanced

Output of a function defined and called in R Console

What is the output of this R code run in the console? add <- function(a, b) { return(a + b) } add(4, 7)

R Programming

add <- function(a, b) {
  return(a + b)
}
add(4, 7)

A [1] 11

B NULL

C [1] 47

D Error: object 'add' not found

💡 Hint

Functions return the sum of their inputs here.

The function add returns the sum of a and b. Calling add(4, 7) returns 11, printed as [1] 11.

❓ Predict Output

advanced

Result of running incomplete R script in console

What error message will appear if you run this incomplete R script in the console? x <- c(1, 2, 3 mean(x)

R Programming

x <- c(1, 2, 3
mean(x)

A Error: unexpected end of input

B [1] 2

C Error: object 'x' not found

D NULL

💡 Hint

Check if all parentheses are closed properly.

The vector c(1, 2, 3 is missing a closing parenthesis, so R reports 'unexpected end of input' error.

🧠 Conceptual

expert

Difference between running code in R Console vs script file

Which statement correctly describes a key difference between running code directly in the R console and running code from an R script file?

A Script files automatically print all variable values, but console does not.

B Code in the console cannot create variables, but script files can.

C Code in the console runs line-by-line immediately, while code in a script file runs only when sourced or executed.

D Console code runs slower than script files because it is interpreted.

💡 Hint

Think about when code executes in each environment.

In R, console code executes immediately line-by-line. Script files contain code that runs only when you source or run the file.