Alt text: get_alt_text

Mix.install([
  {:giggly, path: Path.join(__DIR__, "..")},
  {:kino, "~> 0.19"}
  ])

About this notebook

This notebook follows the examples on ggplot2's reference page for get_alt_text(), in the order the page gives them. Each example shows ggplot2's code first and then Giggly's. An example Giggly cannot draw yet keeps its ggplot2 code and names what it is waiting for, so the page is also a list of what remains.

get_alt_text() returns a plot's alternative text, for a web page to give in place of the drawing: the alt label set with labs(alt = ...), or an empty string when there is none. Giggly has none of this yet: it has no get_alt_text(), and Giggly.Plot.labs/2 takes no alt label.

A plot without alt text

p <- ggplot(mpg, aes(displ, hwy)) +
  geom_point()

# Returns an empty string
get_alt_text(p)

Not in Giggly yet: get_alt_text().

Alt text from labs()

# A user provided alt text
p <- p + labs(
  alt = paste("A scatterplot showing the negative correlation between engine",
              "displacement as a function of highway miles per gallon")
)

get_alt_text(p)

Not in Giggly yet: labs()'s alt label and get_alt_text().