uses_aesthetics: Does a plot use one or more aesthetics?

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

Does a plot use one or more aesthetics?

Description

uses_aesthetics checks whether the student used one or more aesthetics.

Usage

uses_aesthetics(p, aesthetics, 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..
aesthetics	character vector of variables to check for, e.g. "x" or c("x")
local_only	TRUE or FALSE. Should uses_aesthetics only return mappings defined locally in the layer?
exact	If TRUE, variables need to be mapped exactly

Details

By default, uses_aesthetics requires that only one of the aesthetics need to be used. Set exact to TRUE to check if all of the variables have to be matched exactly.

Value

A logical value.

Examples

require(ggplot2)
p <- ggplot(data = mpg, mapping = aes(x = displ, y = hwy)) +
  geom_point(mapping = aes(color = class))
uses_aesthetics(p, "x")
uses_aesthetics(p, c("x", "y"))
uses_aesthetics(get_geom_layer(p, "point"), c("x", "y", "color"), local_only = TRUE)
uses_aesthetics(get_geom_layer(p, "point"), c("x", "y"), local_only = FALSE)

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