uses_mappings: Does a plot or layer use one or more mappings?

In rstudio-education/ggcheck: Inspect 'ggplot2' Plots for Automated Grading in Learning Exercises

Does a plot or layer use one or more mappings?

Description

uses_mappings checks whether the student used one or more mappings in their plot. By default, uses_mappings ignores whether or not the student also supplied additional mappings. Use uses_extra_mappings to check if they did. If exact is TRUE, then all of the mappings have to match exactly.

Usage

uses_mappings(p, mappings, local_only = FALSE, exact = FALSE)

Arguments

p	A ggplot object or a layer extracted from a ggplot object with get_geom_layer or get_stat_layer.
mappings	One or more aesthetic mappings created with aes.
local_only	If TRUE, uses_mappings will check only the mappings defined locally in a layer for the presence of mappings. If FALSE, uses_mappings will check for mappings in the combination of global and local methods that will be used to plot a layer.
exact	If TRUE, mappings need to be mapped exactly

Value

A logical value.

See Also

Other functions for checking mappings: get_mappings(), identical_aes(), ith_mappings_use(), ith_mappings()

Examples

require(ggplot2)
p <- ggplot(data = mpg, mapping = aes(x = displ, y = hwy)) +
  geom_point(mapping = aes(color = class))
uses_mappings(p, aes(x = displ))
uses_mappings(get_geom_layer(p, i = 1), aes(x = displ, color = class), local_only = FALSE)
uses_mappings(get_geom_layer(p, i = 1), aes(x = displ, color = class), local_only = TRUE)
uses_mappings(p, aes(x = displ, y = hwy), exact = TRUE)

rstudio-education/ggcheck documentation built on May 12, 2023, 11:33 a.m.