Highlighting Clusters of Scatter Points with Circle Shapes

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

Section

Use type: "circle" shapes with xref: "x" and yref: "y" to draw circles anchored to data coordinates, overlaying scatter point clusters.

alias Plotly.{Figure, Scatter}

Figure.new()
|> Figure.add_trace(
  Scatter.new(
    x: [0.5, 1.0, 1.5, 2.0, 2.5, 3.5, 4.0, 4.5],
    y: [0.75, 0.5, 1.0, 0.75, 0.9, 3.5, 4.0, 3.75],
    mode: "markers",
    marker: %{size: 10}
  )
)
|> Figure.update_layout(
  title: "Circle Shapes Highlighting Clusters",
  shapes: [
    %{
      type: "circle",
      xref: "x",
      yref: "y",
      x0: 0.25,
      y0: 0.25,
      x1: 2.75,
      y1: 1.25,
      fillcolor: "rgba(50, 171, 96, 0.2)",
      line: %{color: "rgba(50, 171, 96, 0.8)"}
    },
    %{
      type: "circle",
      xref: "x",
      yref: "y",
      x0: 3.25,
      y0: 3.25,
      x1: 4.75,
      y1: 4.25,
      fillcolor: "rgba(214, 39, 40, 0.2)",
      line: %{color: "rgba(214, 39, 40, 0.8)"}
    }
  ]
)
|> Plotly.show()