plotly_ex

Interactive Plotly.js charts for Elixir — works in Livebook via Kino and in Phoenix LiveView.

plotly_ex is an Elixir binding for Plotly — a leading open-source charting library with support for 50+ interactive chart types including statistical, financial, scientific, geographic, and 3D visualisations. Visit plotly.com to explore the full range of chart types and configuration options.

This library was heavily inspired by VegaLite, the Elixir implementation of the Vega-Lite grammar. Like VegaLite, plotly_ex provides both a concise Express API for rapid chart creation and a fluent builder API for fine-grained control — with first-class Livebook and Phoenix LiveView integration courtesy of Kino.

• Express API — one-call chart building from lists-of-maps or Explorer DataFrames
• Fluent builder — compose traces and layouts step-by-step
• SmartCell — no-code chart builder in Livebook
• Phoenix LiveView component with live reactive updates
• 50+ Plotly.js trace types (scatter, bar, heatmap, 3D, maps, financial, …)
• Live updates via PlotlyLive.push/2
• Browser event subscriptions (click, hover, zoom)

---

Installation

In a Livebook notebook (Mix.install):

Mix.install([
  {:plotly_ex, "~> 0.1"},
  {:kino, "~> 0.14"},
  # optional — pass Explorer DataFrames to Express functions:
  {:explorer, "~> 0.11"}
])

In a Mix project (mix.exs):

def deps do
  [
    {:plotly_ex, "~> 0.1"},
    # Optional integrations:
    {:kino, "~> 0.14", optional: true},            # Livebook
    {:explorer, "~> 0.11", optional: true},         # Explorer DataFrames
    {:phoenix_live_view, "~> 1.0", optional: true}  # Phoenix LiveView
  ]
end

---

Livebook

Express API

One call to chart from a list of maps:

data = [
  %{"month" => "Jan", "sales" => 42},
  %{"month" => "Feb", "sales" => 55},
  %{"month" => "Mar", "sales" => 38}
]
Plotly.bar(data, x: "month", y: "sales", title: "Monthly Sales")
|> Plotly.show()

Or from an Explorer DataFrame:

df = Explorer.DataFrame.new(x: [1, 2, 3], y: [10, 20, 15])
Plotly.scatter(df, x: "x", y: "y", title: "From DataFrame")
|> Plotly.show()

Fluent Builder

For full control over trace properties:

alias Plotly.{Figure, Scatter}

Figure.new()
|> Figure.add_trace(Scatter.new(x: [1, 2, 3], y: [4, 5, 6], name: "A"))
|> Figure.add_trace(Scatter.new(x: [1, 2, 3], y: [6, 5, 4], name: "B"))
|> Figure.update_layout(title: "Two Traces", width: 700)
|> Plotly.show()

Nested trace options (marker, line, etc.) accept plain maps:

Scatter.new(
  x: [1, 2, 3], y: [4, 5, 6],
  marker: %{color: "red", size: 10},
  line: %{dash: "dot"}
)

SmartCell (no-code chart builder)

The SmartCell is auto-registered when kino is present — no setup needed.

1. In Livebook, click + Smart cell → choose Plotly Chart
2. Pick a variable (DataFrame or list of maps), chart type, and column axes
3. Click + Add layer to overlay multiple traces
4. Generated code can be copied and edited freely

Multi-Trace / Layering

Figure.merge/2 combines traces from two figures while preserving the first figure's layout:

Plotly.scatter(df, x: "date", y: "price")
|> Plotly.Figure.merge(Plotly.bar(df, x: "date", y: "volume"))
|> Plotly.show()

Live Updates & Events

PlotlyLive lets you push updates to an already-displayed chart and subscribe to browser events:

chart = Plotly.Kino.PlotlyLive.new(initial_figure)

# Push a new figure without re-evaluating the cell:
Plotly.Kino.PlotlyLive.push(chart, updated_figure)

# Subscribe to browser events with a tag:
Plotly.Kino.PlotlyLive.subscribe(chart, :chart_events)

receive do
  {:chart_events, %{"type" => "plotly_click", "data" => data}} ->
    IO.inspect(data["points"])
end

Filter to a specific event type:

Plotly.Kino.PlotlyLive.subscribe(chart, :chart_events, :click)
Plotly.Kino.PlotlyLive.subscribe(chart, :chart_events, :hover)
Plotly.Kino.PlotlyLive.subscribe(chart, :chart_events, :relayout)
Plotly.Kino.PlotlyLive.subscribe(chart, :chart_events, :selected)

---

Phoenix

Static Embed (no LiveView)

For controller-rendered (dead) views, use static_plot/2 — no hook registration needed.

1. Add Plotly.js to your layout (lib/your_app_web/components/layouts/app.html.heex):

<script src="https://cdn.plot.ly/plotly-2.35.2.min.js"></script>

2. Build the figure in your controller:

def index(conn, _params) do
  monthly = [
    %{"month" => "Jan", "sales" => 42},
    %{"month" => "Feb", "sales" => 55},
    %{"month" => "Mar", "sales" => 61},
    %{"month" => "Apr", "sales" => 48},
    %{"month" => "May", "sales" => 73}
  ]
  figure = Plotly.bar(monthly, x: "month", y: "sales", title: "Monthly Sales")
  render(conn, :index, figure: figure)
end

3. Embed in your template (lib/your_app_web/controllers/chart_html/index.html.heex):

<%= Plotly.Phoenix.Component.static_plot(@figure, id: "my-chart") %>

static_plot/2 returns {:safe, html}. Plotly.js renders the chart on page load.

---

LiveView

1. Add Plotly.js to your layout (lib/your_app_web/components/layouts/app.html.heex):

<script src="https://cdn.plot.ly/plotly-2.35.2.min.js"></script>

2. Register the hook (assets/js/app.js):

Import directly from the library (includes event forwarding, render-race protection, and RawJS support):

import { PlotlyChart } from "../../deps/plotly_ex/priv/static/plotly_hook.js"

let liveSocket = new LiveSocket("/live", Socket, {
  hooks: { PlotlyChart }
})

Or vendor a minimal hook by saving this to assets/js/plotly_hook.js:

// assets/js/plotly_hook.js
export const PlotlyChart = {
  mounted() {
    const fig = JSON.parse(this.el.dataset.figure);
    Plotly.newPlot(this.el, fig.data || [], fig.layout || {}, fig.config || {});
    this._observer = new ResizeObserver(() => Plotly.Plots.resize(this.el));
    this._observer.observe(this.el);
  },
  updated() {
    const fig = JSON.parse(this.el.dataset.figure);
    Plotly.react(this.el, fig.data || [], fig.layout || {}, fig.config || {});
  },
  destroyed() {
    if (this._observer) this._observer.disconnect();
    Plotly.purge(this.el);
  }
};

Then import it in app.js:

import { PlotlyChart } from "./plotly_hook.js"

The full hook in deps/plotly_ex/priv/static/plotly_hook.js adds click/hover/zoom event forwarding to LiveView, render-race protection, and RawJS support — use it if you need those features.

3. Use the component in your .heex template:

<Plotly.Phoenix.Component.plot id="my-chart" figure={@figure} />

4. Build figures and handle events in your LiveView:

def mount(_params, _session, socket) do
  data = [%{"x" => 1, "y" => 4}, %{"x" => 2, "y" => 7}, %{"x" => 3, "y" => 3}]
  {:ok, assign(socket, figure: Plotly.scatter(data, x: "x", y: "y", title: "Live Chart"))}
end

def handle_event("plotly_click", %{"data" => %{"points" => points}}, socket) do
  IO.inspect(points, label: "clicked")
  {:noreply, socket}
end

The component calls Plotly.react on each assign update — only changed data is re-rendered.

---

Notebooks

The notebooks/ directory contains 16 runnable Livebook examples covering every chart type.

How to open them:

1. Start Livebook: livebook server (or open the Livebook desktop app)
2. Click Open → navigate to this repo's notebooks/ folder
3. Open any .livemd file and run the cells

Notebook	Coverage
01_express.livemd	Express API: all chart types in one call
02_builder.livemd	Fluent builder, trace options
03a_fundamentals_config.livemd	Configuration & display settings
03b_fundamentals_styling.livemd	Colors, axes, hover templates
03c_fundamentals_shapes.livemd	Shapes & annotations
04_basic_charts.livemd	Scatter, bar, pie, table, WebGL
05_statistical.livemd	Histogram, box, violin, heatmap
06_scientific.livemd	Contour, surface, 3D, polar
07_financial.livemd	Candlestick, OHLC, waterfall
08_maps.livemd	Choropleth, scatter geo, tile maps
09_3d.livemd	3D scatter, surface, mesh
10_subplots.livemd	Grid layouts, shared axes
11_custom_controls.livemd	Buttons, sliders, dropdowns
12_animations.livemd	Frame-based animations
13_chart_events.livemd	Click, hover, zoom events
14_kino_smart_cell.livemd	SmartCell walkthrough

---

Example Phoenix Project (phx_ex/)

phx_ex/ is a standalone Phoenix application demonstrating plotly_ex integration in a LiveView.

Run it:

cd phx_ex
mix deps.get
mix assets.build
mix phx.server
# Visit http://localhost:4000

Two routes are included:

• / — LiveView demo (lib/phx_ex_web/live/plots_live.ex): mount figures, update on interaction, handle plotly_click events.
• /static — Controller demo (lib/phx_ex_web/controllers/static_plot_controller.ex): static_plot/2 in a plain controller with no WebSocket connection.

---

Configuration

# config/config.exs
config :plotly_ex, :plotly_js,
  version: "2.35.2",  # Plotly.js version loaded from CDN
  source: :cdn        # :cdn (default)

---

License

MIT License — see LICENSE for details.

MIT License

Copyright (c) 2026 plotly_ex contributors

Permission is hereby granted, free of charge, to any person obtaining a copy
of this software and associated documentation files (the "Software"), to deal
in the Software without restriction, including without limitation the rights
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copies of the Software, and to permit persons to whom the Software is
furnished to do so, subject to the following conditions:

The above copyright notice and this permission notice shall be included in all
copies or substantial portions of the Software.

THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
SOFTWARE.