Two Y-Axes

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

Section

Two y-axes on one chart: the second y-axis uses overlaying: "y" to share the same x-axis and plot area. side: "right" puts it on the right. The trace referencing it sets yaxis: "y2".

alias Plotly.{Figure, Scatter}

x = ["Jan", "Feb", "Mar", "Apr", "May", "Jun"]
y1 = [1000, 1200, 900, 1400, 1100, 1300]
y2 = [22, 19, 25, 18, 23, 20]

Figure.new()
|> Figure.add_trace(
  Scatter.new(x: x, y: y1, name: "Revenue ($)", mode: "lines+markers")
)
|> Figure.add_trace(
  Scatter.new(x: x, y: y2, name: "Temperature (°C)", mode: "lines+markers", yaxis: "y2")
)
|> Figure.update_layout(
  title: "Two Y-Axes",
  yaxis: %{title: %{text: "Revenue ($)"}},
  yaxis2: %{
    title: %{text: "Temperature (°C)"},
    overlaying: "y",
    side: "right"
  }
)
|> Plotly.show()