Free R Programming Language MCQ Questions and Answers

Question 1

What R syntax should I use to output "Hello World"?

Accepted Answer

All of the other answers are correct

Answer

In R, simply typing a string literal like `"Hello World"` or `'Hello World'` into the console will cause R to echo its value as output. Additionally, the `print()` function is explicitly designed to display its arguments to the console. Therefore, all listed options are valid ways to output "Hello World" in R.

Question 2

R is a React alias.

Accepted Answer

FALSE

Answer

R is a programming language and software environment specifically designed for statistical computing and graphics. React, on the other hand, is a JavaScript library used for building user interfaces. They are entirely different technologies serving distinct purposes and are not related or aliases of each other.

Question 3

In R code, how do you add comments?

Accepted Answer

# This is a comment

Answer

In R, the hash symbol `#` is used to denote a comment. Any text following `#` on a line is ignored by the R interpreter, allowing developers to add explanatory notes within their code. This is the standard and only single-line comment syntax in R.

Question 4

You must specify a variable's data type in R.

Accepted Answer

FALSE

Answer

R is a dynamically typed language, meaning you do not need to explicitly declare the data type of a variable when you create it. The R interpreter automatically infers the data type based on the value assigned to the variable. For example, assigning `x <- 5` makes `x` an integer, and `y <- "hello"` makes `y` a character string without prior declaration.

Question 5

How do you make the variable x have the number 5 as its value?

Accepted Answer

x <- 5

Answer

In R, the `<-` operator is the primary and idiomatic way to assign a value to a variable. It assigns the value on its right to the variable on its left. While `=` can also be used for assignment, `<-` is generally preferred and more common in R programming style.

R Programming Language Certification Practice Test

R Programming Language Certification Practice Test

Free R Programming Language MCQ Questions and Answers