Categorical Polar Chart

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

Section

When theta: is a list of strings, set layout.polar.angularaxis.type: "category". Plotly places the categories at equal angular spacing around the circle. layout.polar.angularaxis.categoryarray: overrides the display order.

alias Plotly.{Figure, Scatterpolar}

months = ["Jan", "Feb", "Mar", "Apr", "May", "Jun",
          "Jul", "Aug", "Sep", "Oct", "Nov", "Dec", "Jan"]
rain   = [50, 40, 45, 60, 80, 90, 100, 95, 75, 55, 50, 45, 50]
temp   = [5,  7,  12, 17, 21, 25,  27,  26, 22, 16, 10,  6,  5]

Figure.new()
|> Figure.add_trace(
  Scatterpolar.new(
    r: rain,
    theta: months,
    mode: "lines+markers",
    fill: "toself",
    name: "Rainfall (mm)"
  )
)
|> Figure.add_trace(
  Scatterpolar.new(
    r: temp,
    theta: months,
    mode: "lines+markers",
    fill: "toself",
    name: "Temperature (°C)"
  )
)
|> Figure.update_layout(
  title: "Categorical Polar Chart — Monthly Climate",
  polar: %{angularaxis: %{type: "category"}}
)
|> Plotly.show()