Categorical Axes

Mix.install([
  {:plotly_ex, "~> 0.3"},
  {:kino, "~> 0.18"}
])

Section

When x (or y) values are strings, plotly automatically creates a categorical axis. Set type: "category" explicitly to force categorical treatment even for numeric-looking labels, or to control category ordering via categoryorder/categoryarray.

alias Plotly.{Figure, Bar}

x = ["giraffes", "orangutans", "monkeys"]
y = [20, 14, 23]

Figure.new()
|> Figure.add_trace(Bar.new(x: x, y: y))
|> Figure.update_layout(title: "Categorical Axes (auto-detected)")
|> Plotly.show()

alias Plotly.{Figure, Scatter}

x = ["cat1", "cat2", "cat3", "cat4"]
y = [2, 6, 3, 8]

Figure.new()
|> Figure.add_trace(Scatter.new(x: x, y: y, mode: "markers", marker: %{size: 14}))
|> Figure.update_layout(
  title: "Categorical Axis — Explicit Order",
  xaxis: %{
    type: "category",
    categoryorder: "array",
    categoryarray: ["cat3", "cat1", "cat4", "cat2"]
  }
)
|> Plotly.show()