# Particle Flow (Sankey example)

> WestCoast Charts 1.1.5, release, public Core release, on npm. HTML: https://westcoast-charts.com/gallery/sankey/particle-flow/ · Index for agents: https://westcoast-charts.com/llms.txt

Particles travel along each link; their density follows the flow.

- Chart type: `sankey` (Sankey)
- Collection: Sankey · Sankey
- Raw configuration: https://westcoast-charts.com/gallery-src/sankey/particle-flow.js
- Standalone example: https://westcoast-charts.com/embed/samples/wcc/gallery/premium/sankey/particle-flow.html

## Setup

```js
import WestCoastCharts from 'west-coast-charts'
import types from 'west-coast-charts/types'
import premium from 'west-coast-charts/premium'

WestCoastCharts.use(types).use(premium)
const WestCoastChartsPremium = premium
WestCoastCharts.setLicenseKey(LICENCE_KEY) // paid production licence; localhost evaluation needs no key
```

## Options

```js
const options = {
  chart: {
    height: 380,
    toolbar: {
      show: false
    },
    type: "sankey"
  },
  series: [
    {
      data: [
        ["Ingest", "Queue", 80],
        ["Queue", "Workers", 74],
        ["Queue", "Dead letter", 6],
        ["Workers", "Storage", 52],
        ["Workers", "Search index", 22]
      ]
    }
  ],
  plotOptions: {
    sankey: {
      link: {
        colorMode: "source",
        particles: {
          enabled: true,
          density: 1.2,
          speed: 1
        }
      }
    }
  },
  theme: {
    mode: "light",
    preset: "coastal"
  }
}

const chart = new WestCoastCharts(document.querySelector('#chart'), options)
await chart.render()
```

## Verify

- Text check (Library 1.1.5): load `west-coast-charts/agent/describe` and call `chart.describe({ format: "json" })` for the actual drawn state. The live reader is on this example’s HTML page.
- Command line (Public agent tools 0.2.3, tested with Library 1.1.5; available from the versioned GitHub release and npm, https://westcoast-charts.com/docs/cli/index.md): `wcc chart export sankey-particle-flow.json --out sankey-particle-flow.svg --with-table` (save the options above as JSON first)