How do I create a circos heatmap chart in JavaScript?

Install with `npm install katucharts.js`, import the module with `import 'katucharts.js/bio';`, then call KatuCharts.chart(container, { chart: { type: 'circosheatmap' }, series: [...] }).

Why does my circos heatmap chart render as a line chart?

The chart type was not registered. KatuCharts logs "KatuCharts: unknown series type " ", falling back to line" and draws a line chart rather than throwing. Import the module the type belongs to — for example `import 'katucharts.js/bio';` — before creating the chart.

Why do I get "Cannot read properties of null (reading 'appendChild')"?

The container element does not exist when the chart is created. Create the chart after the element is in the DOM: in React that means inside useEffect, not during render.

Why is the chart rendering with zero height?

The container has no height. A div with no content collapses to zero. Give it a height in CSS, or pass `chart: { height: 400 }` in the options.

Bioinformatics · katucharts.js/bio

Circos Heatmap

type: 'circosheatmap'

Matrix heatmap wrapped onto a ring — rows become angular sectors, columns become concentric bands. Ideal for expression or abundance matrices.

Edit the JSON on the right and press Run (or ⌘/Ctrl + Enter) — data, titles, categories and colors all update live.

Live

Circos Heatmap

Edit · JSON

{
  "chart": {
    "type": "circosHeatmap"
  },
  "title": {
    "text": "Expression Rings"
  },
  "series": [
    {
      "name": "Expression",
      "colorScale": "Viridis",
      "innerRadius": 0.35,
      "data": [
        {
          "custom": {
            "columns": [
              "Ctrl",
              "1h",
              "6h",
              "12h",
              "24h",
              "48h"
            ],
            "rows": [
              {
                "id": "IL6",
                "values": [
                  0,
                  0.2,
                  5.2,
                  8.4,
                  9.9,
                  10
                ]
              },
              {
                "id": "TNF",
                "values": [
                  4.5,
                  0,
                  0.6,
                  0.5,
                  5.4,
                  1.6
                ]
              },
              {
                "id": "BRCA1",
                "values": [
                  8.4,
                  7.4,
                  3.2,
                  5.7,
                  9.5,
                  0.5
                ]
              },
              {
                "id": "TP53",
                "values": [
                  5.3,
                  1.6,
                  2,
                  0.9,
                  6.9,
                  4.7
                ]
              },
              {
                "id": "MYC",
                "values": [
                  9.2,
                  1.9,
                  6,
                  5.9,
                  9.9,
                  0.6
                ]
              },
              {
                "id": "EGFR",
                "values": [
                  7.1,
                  4.2,
                  9.6,
                  5,
                  8.4,
                  9.7
                ]
              },
              {
                "id": "VEGFA",
                "values": [
                  6.7,
                  6.3,
                  7.7,
                  0.5,
                  8.4,
                  6.1
                ]
              },
              {
                "id": "CASP3",
                "values": [
                  0,
                  2.1,
                  2.6,
                  9.6,
                  5.3,
                  2
                ]
              }
            ]
          }
        }
      ]
    }
  ]
}

Data format

custom: { columns: [...], rows: [{ id, values: [...], color }] }

Data shape

The JSON you pass inside the chart — drop it straight into your series.

data: [{
  custom: {
    columns: ['Ctrl', '24h', '48h'],
    rows: [
      { id: 'IL6', values: [2.1, 8.4, 5.0] },
      { id: 'TNF', values: [3.2, 7.1, 4.8] }
    ]
  }
}]

Example

KatuCharts.chart('container', {
  series: [{ type: 'circosHeatmap', colorScale: 'Viridis', data: [{ custom: {
    columns: ['Ctrl', '24h', '48h'],
    rows: [{ id: 'IL6', values: [2.1, 8.4, 5.0] }]
  } }] }]
});

Type-specific options

Option	Description
`colorScale`	Named sequential scale (e.g. 'Viridis').
`innerRadius`	Hollow-center ratio (0–1).
`min / max`	Clamp the color domain.

Common errors

Why does my circos heatmap chart render as a line chart?: The chart type was not registered. KatuCharts logs "KatuCharts: unknown series type "<type>", falling back to line" and draws a line chart rather than throwing. Import the module the type belongs to — for example `import 'katucharts.js/bio';` — before creating the chart.
Why do I get "Cannot read properties of null (reading 'appendChild')"?: The container element does not exist when the chart is created. Create the chart after the element is in the DOM: in React that means inside useEffect, not during render.
Why is the chart rendering with zero height?: The container has no height. A div with no content collapses to zero. Give it a height in CSS, or pass `chart: { height: 400 }` in the options.

FAQ

How do I create a circos heatmap chart in JavaScript?: Install with `npm install katucharts.js`, import the module with `import 'katucharts.js/bio';`, then call KatuCharts.chart(container, { chart: { type: 'circosheatmap' }, series: [...] }).
Why does my circos heatmap chart render as a line chart?: The chart type was not registered. KatuCharts logs "KatuCharts: unknown series type "<type>", falling back to line" and draws a line chart rather than throwing. Import the module the type belongs to — for example `import 'katucharts.js/bio';` — before creating the chart.
Why do I get "Cannot read properties of null (reading 'appendChild')"?: The container element does not exist when the chart is created. Create the chart after the element is in the DOM: in React that means inside useEffect, not during render.
Why is the chart rendering with zero height?: The container has no height. A div with no content collapses to zero. Give it a height in CSS, or pass `chart: { height: 400 }` in the options.

Common options (color, visible, marker, dataLabels, animation, events, zones…) apply to every type — see Configuration → series. See it rendered in the gallery.