knitr::opts_chunk$set(echo = FALSE)

Topic 1


Here's a simple exercise with an empty code chunk provided for entering the answer.

Write the R code required to add two plus two:

Exercise with Code

Here's an exercise with some prepopulated code as well as exercise.lines = 5 to provide a bit more initial room to work.

Now write a function that adds any two numbers and then call it:

add <- function() {


Topic 2

Exercise with Hint

Here's an exercise where the chunk is pre-evaulated via the exercise.eval option (so the user can see the default output we'd like them to customize). We also add a "hint" to the correct solution via the chunk immediate below labeled print-limit-hint.

Modify the following code to limit the number of rows printed to 5:



You can include any number of single or multiple choice questions as a quiz. Use the question function to define a question and the quiz function for grouping multiple questions together.

Some questions to verify that you understand the purposes of various base and recommended R packages:

  question("Which package contains functions for installing other R packages?",
    answer("utils", correct = TRUE),
  question("Which of the R packages listed below are used to create plots?",
    answer("lattice", correct = TRUE),
    answer("grid", correct = TRUE)

Try the learnr package in your browser

Any scripts or data that you put into this service are public.

learnr documentation built on March 26, 2020, 7:45 p.m.