tbl_check_column: Checks that a column is identical across two tables

In rstudio/tblcheck: Grade Tables in Learning Exercises

Checks that a column is identical across two tables

Description

Checks for differences between the name column in object and in expected in the following order:

1. Check that the name column exists in object

2. Check class with vec_check_class()

3. Check length with vec_check_dimensions()

4. If the column is a factor, check factor levels with vec_check_levels()

5. Check column values with vec_check_values()

If the columns differ

• tbl_check_column() returns a list describing the problem

• tbl_grade_column() returns a failing grade and informative message with gradethis::fail()

Usage

tbl_check_column(
  column,
  object = .result,
  expected = .solution,
  check_class = TRUE,
  ignore_class = NULL,
  check_length = TRUE,
  check_levels = TRUE,
  check_values = TRUE,
  tolerance = sqrt(.Machine$double.eps),
  check_names = FALSE,
  env = parent.frame()
)

tbl_grade_column(
  column,
  object = .result,
  expected = .solution,
  max_diffs = 3,
  check_class = TRUE,
  ignore_class = NULL,
  check_length = TRUE,
  check_levels = TRUE,
  check_values = TRUE,
  tolerance = sqrt(.Machine$double.eps),
  check_names = FALSE,
  env = parent.frame(),
  ...
)

Arguments

column	[character(1)] The name of the column to check.
object	A data frame to be compared to expected.
expected	A data frame containing the expected result.
check_class	[logical(1)] Whether to check that column has the same class in object and expected.
ignore_class	[character()] A vector of classes to ignore when finding differences between object and expected. If an element is named, differences will only be ignored between the pair of the element and its name. For example, ignore_class = c("integer" = "numeric") will ignore class differences only if object has class integer and expected has class numeric, or vice versa. If all the classes of expected are included in ignore_class, a class problem will never be returned.
check_length	[logical(1)] Whether to check that column has the same length in object and expected.
check_levels	[logical(1)] Whether to check that column and has the same factor levels in object and expected.
check_values	[logical(1)] Whether to check that column has the same values in object and expected.
tolerance	[numeric(1) ≥ 0] values differences smaller than tolerance are ignored. The default value is close to 1.5e-8.
check_names	[logical(1)] Whether to check that column has the same names in object and expected. Defaults to FALSE.
env	The environment in which to find .result and .solution.
max_diffs	[numeric(1)] The maximum number of mismatched values to print. Defaults to 3.
...	Arguments passed on to gradethis::fail hint Include a code feedback hint with the failing message? This argument only applies to fail() and fail_if_equal() and the message is added using the default options of give_code_feedback() and maybe_code_feedback(). The default value of hint can be set using gradethis_setup() or the gradethis.fail.hint option. encourage Include a random encouraging phrase with random_encouragement()? The default value of encourage can be set using gradethis_setup() or the gradethis.fail.encourage option.

Value

If there are any issues, a list from tbl_check_column() or a gradethis::fail() message from tbl_grade_column(). Otherwise, invisibly returns NULL.

Problems

1. names (table_problem): object doesn't contain a column named column.

2. class: Any mismatch in the classes of the column.

3. length: The column doesn't have the expected length.

4. levels_n, levels, levels_reversed, levels_order: See vec_check_levels().

5. values: The column doesn't have the expected values.

6. names (column_problem): The column has different names than expected.

7. names_order: The column has the same names as expected, but in a different order.

Examples

.result <- tibble::tibble(a = 1:10, b = 11:20)
.solution <- tibble::tibble(a = letters[1:10], b = letters[11:20])
tbl_check_column("a")
tbl_grade_column("a")

.result <- tibble::tibble(a = 1:10, b = 11:20)
.solution <- tibble::tibble(a = 1:11, b = 12:22)
tbl_check_column("a")
tbl_grade_column("a")

.result <- tibble::tibble(a = 1:10, b = 11:20)
.solution <- tibble::tibble(a = 11:20, b = 1:10)
tbl_check_column("a")
tbl_grade_column("a")
tbl_grade_column("a", max_diffs = 5)
tbl_grade_column("a", max_diffs = Inf)

rstudio/tblcheck documentation built on March 11, 2023, 5:42 p.m.