define_an_exercise: Define an exercise

Description

Defines an exercise with random components.

Usage

define_an_exercise(ex, type, statement, image, image_alt, answer, ...)
# S3 method for exam
define_an_exercise(
  ex,
  type = "",
  statement = "",
  image = "",
  image_alt = "",
  answer = "",
  ...
)

Value

An `exam`.

Arguments

ex: An `exam` object.
type: A character, 'p' indicates whether the exercise starts on a new page.
statement: A string, statement of the exercise.
image: A string, optional, image file to include in the exercise.
image_alt: A string, description of the image to include in the exercise.
answer: A string, correct answer to the exercise.
...: A string, options for the gaps in the exercise.

Details

If an image is included in the exercise, text in the `image_alt` field associated with it must also be included.

Following the answer, options can be defined to fill in the gaps that have been specified in the exercise.

Both the answer and the options are formed by a vector of strings, from which one is chosen to formulate the exercise and select the answer. To represent a vector of strings in a cell, the function `vector_to_string()` is used, which includes a separator ("<|>") between the vector elements to generate a string.

Examples

Run this code


rmd <- system.file("extdata/template01.Rmd", package = "rexer")
ex <- exam(
  rmd = rmd,
  examinees = NULL,
  instances_num = 10,
  random = TRUE,
  reorder_exercises = TRUE,
  select_n_exercises = NULL
) |>
  define_an_exercise(
    type = 'p',
    statement = 'What is the three-letter country code (ISO 3166-1 alpha-3) for
    the country represented in the figure below?',
    image = paste0(system.file("extdata/figures", package = "rexer"), "/", '[[1]]'),
    image_alt = 'Country outline.',
    answer = c('ESP', 'CHL', 'NZL', 'ITA'),
    c('spain.png', 'chile.png', 'new_zealand.png', 'italy.png')
  )