gradethis_equal: Compare the values of two objects to check whether they are...

In rstudio-education/grader: Automated Feedback for Student Exercises in 'learnr' Tutorials

Compare the values of two objects to check whether they are equal

Description

Compare the values of two objects to check whether they are equal

Usage

gradethis_equal(x = .result, y = .solution, ...)

## Default S3 method:
gradethis_equal(x, y, tolerance = sqrt(.Machine$double.eps), ...)

## S3 method for class 'list'
gradethis_equal(x, y, tolerance = sqrt(.Machine$double.eps), ...)

Arguments

x, y	Two objects to compare
...	Additional arguments passed to methods
tolerance	If non-NULL, used as threshold for ignoring small floating point difference when comparing numeric vectors. Using any non-NULL value will cause integer and double vectors to be compared based on their values, not their types, and will ignore the difference between NaN and NA_real_. It uses the same algorithm as all.equal(), i.e., first we generate x_diff and y_diff by subsetting x and y to look only locations with differences. Then we check that mean(abs(x_diff - y_diff)) / mean(abs(y_diff)) (or just mean(abs(x_diff - y_diff)) if y_diff is small) is less than tolerance.

Value

A logical value of length one, or an internal gradethis error.

Methods (by class)

• gradethis_equal(default): The default comparison method, which uses waldo::compare

• gradethis_equal(list): The comparison method for lists

Examples

gradethis_equal(mtcars[mtcars$cyl == 6, ], mtcars[mtcars$cyl == 6, ])
gradethis_equal(mtcars[mtcars$cyl == 6, ], mtcars[mtcars$cyl == 4, ])

rstudio-education/grader documentation built on July 6, 2023, 8:48 a.m.