Multi Category Waterfall Chart

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

Section

Hierarchical x: uses a list of two lists — outer and inner category labels — creating a multi-level x-axis. base: 1000 shifts the starting value of all bars. nil (nil in Elixir) as a y value for "total" bars lets Plotly compute the running total automatically. layout.waterfallgroupgap: controls spacing between groups.

alias Plotly.{Figure, Waterfall}

outer = ["2016", "2017", "2017", "2017", "2017", "2018", "2018", "2018", "2018"]
inner = ["initial", "q1", "q2", "q3", "total", "q1", "q2", "q3", "total"]

measure = [
  "absolute",
  "relative",
  "relative",
  "relative",
  "total",
  "relative",
  "relative",
  "relative",
  "total"
]

Figure.new()
|> Figure.add_trace(
  Waterfall.new(
    x: [outer, inner],
    measure: measure,
    y: [1, 2, 3, -1, nil, 1, 2, -4, nil],
    base: 1000
  )
)
|> Figure.add_trace(
  Waterfall.new(
    x: [outer, inner],
    measure: measure,
    y: [1.1, 2.2, 3.3, -1.1, nil, 1.1, 2.2, -4.4, nil],
    base: 1000
  )
)
|> Figure.update_layout(
  waterfallgroupgap: 0.5,
  xaxis: %{title: %{text: "MULTI-CATEGORY"}, tickfont: %{size: 16}, ticks: "outside"}
)
|> Plotly.show()