Sunburst Charts

Overview

JavaScript sunburst charts or graphs display data as proportional slices of a circular pie surrounded by hierarchical rings. They are also known as multi-level pie charts, Ring Chart, and Radial Treemap. You can create interactive sunburst charts by incorporating features such as animation, legends, and drilldown. Browse our ZingChart Gallery for inspiration and ideas.

Chart Type

To specify the chart type, add a type attribute to the chart object and provide the value: sunburst. Our standard sunburst chart is specified by the sunburst value. Without further modification, here is how the default sunburst chart appears.

{
  	type: 'sunburst',
    title: {
    	text: "Sunburst Chart"
    },
    series: chartData 
}

Series Data

Provide your chart data in the series array. In the series array, create an object and assign a value to id, text, parent, and the optional value attribute. id is the section where the series data object will be placed, text is the text that will be displayed in that section, parent is the parent section of the section you are adding data to, and value is the numerical value of the data object being added.

series: [
  {id: 'flare', text: 'flare', parent: ''},
  {id: 'analytics', text: 'analytics', parent: 'flare'},
  {id: 'cluster', text: 'cluster', parent: 'analytics'},
  {id: 'agglomerativecluster', text: 'AgglomerativeCluster', parent: 'cluster', value: 3938},
  ...,
  {id: 'someId', text: 'someText', parent: 'someParent', values: [someValue]}
]

Note that you can have ZingChart automatically order your sunburst slices, from largest to smallest. Create a plot object and add a layoutattribute. Set the value to auto. (This attribute also sets the pie chart’s default reference angle to 12 o'clock, or zero degrees. For more information, see the Reference Angle section below.)

Basic Elements

Once you've provided your sunburst chart type and data, you can configure the chart's basic elements such as the aperture, reference angle, size factor, donut ring size, how pie slices are detached, offset, and/or clicked, and more.

Scale Configuration

Use the scale-r object to set the pie chart's aperture and reference angle. Use the scale object to set the size factor.

Aperture

The pie chart is sized to 360 degrees (i.e., a circle) by default. You can change this by adding an aperture attribute to the scale-r object. Provide the desired aperture value, e.g., 180 is a half circle, 90 is a quarter circle, and so on.

{
  type: 'sunburst',
  title: {
    text: "'aperture' attribute"
  },
  'scale-r': {
    aperture:300
  },
  series: chartData
}

Reference Angle

The reference angle (or starting point) of our pie charts is set to 90 degrees (or 3 o'clock) by default. Add a ref-angleattribute to the scale-r object to change this. Provide the desired value, keeping in mind that the value is relative to the default starting angle. E.g., providing a value of 270 would make the first pie slice appear at the 12 o'clock position. See the below chart.

{
  type: 'sunburst',
  title: {
    text: "'ref-angle' attribute"
  },
  'scale-r': {
    'ref-angle':270 //relative to the starting 90 degree position.
  },
  series: chartData
}

'lternatively, you can have the reference angle automatically set to zero and have the sunburst slices automatically sorted by size, from largest to smallest, by adding a layout': "auto attribute to the plot object. See the below chart.

{
  type: 'sunburst',
  title: {
    text: "'layout' attribute in 'plot' object"
  },
  plot: {
    layout: "auto" //to order pie slices by size and have reference angle start at zero.
  },
  series: chartData
}

Chart-Specific

Sunburst chart-specific customizations include modifying the size of the donut ring, allowing for the reattachment of detached pie slices, setting up offset pie slices, and disabling the detachment of clicked pie slices.

Offset Slices

Use the offset-r attribute to pull out one or more slices from the rest of the pie. Often referred to as an exploded pie chart, the attribute can be applied globally (plot object) or locally (series object). Provide the pie slice offset as a percentage or pixel value.

{
  type: "sunburst",
  title: {
    text: "'offset-r' attribute"
  },
  plot: {
    'offset-r': "10%"
  },
  series: chartData
}

Plot/Series Styling

You can style the borders of the sunburst slices using the border-width, border-color, line-style, alpha, and other styling attributes. Refer to the Plot/Series Styling Tutorial and the Plot/Series JSON page for further information and a full attribute list.

{
  type: 'sunburst',
  title: {
    text: "Sunburst Chart Styling"
  },
  plot: {
    'border-width': 1,
    'border-color': "#cccccc",
    'line-style': "dotted"
  },
  series: chartData
}

Tokens

Tokens (or string interpolation) are highly useful when customizing sunburst chart tooltips and value boxes. Commonly used sunburst chart tokens include:

Refer to the Tokens Tutorial for a full list of available tokens.

Tooltips

Tooltips appear when you hover over the sunburst slices. Create a tooltip object in the plot object to customize the text and styling. Refer to the Tooltips Tutorial and Tooltips JSON page for more information and a full attribute list.

{
  type: 'sunburst',
  title: {
    text: "Tooltips"
  },
  subtitle: {
    text: "Hover over the sunburst slices",
    'font-weight': "normal"
  },
  plot: {
    tooltip: {
      text: "%t: %v (%npv%)",
      'font-color': "black",
      'font-family': "Georgia",
      'text-alpha':1,
      'background-color': "white",
      alpha:0.7,
      'border-width': 1,
      'border-color': "#cccccc",
      'line-style': "dotted",
      'border-radius': "10px",
      padding: "10%",
      placement: "node:out" //"node:out" or "node:center"
    },
    ...omitted for brevity...
  },
  series: chartData
}

Value Boxes

Value boxes are fixed labels that appear adjacent to the sunburst slices. Create a value-box object in the plot object to customize the text, placement (in, out, center), and styling. You can also incorporate rules. Refer to the Value Boxes Tutorial and the Value Boxes JSON page for more information and a full attribute list.

In the below chart, rules were used to place value boxes in or out of the chart based on their value.

Tip: Value boxes placed outside the sunburst slices are automatically drawn with connecting lines. To remove them, add a connected attribute and set the value to false.

{
  type: 'sunburst',
  title: {
    text: "Value Boxes"
  },
  subtitle: {
    text: "with placement set to 'in' and 'out' based on the node value",
    'font-weight': "normal"
  },
  plot: {
    'value-box': {
      text: "%v",
      'font-size':12,
      'font-family': "Georgia",
      'font-weight': "normal",
      rules: [
        {
          rule: "%v > 6000",
          placement: "in",
          'offset-r': "50%",
          'font-color': "white",
        },
        {
          rule: "%v <= 6000",
          placement: "out",
          'font-color': "gray",
        }
      ]
    },
    ...omitted for brevity...
  },
  series: chartData
}

Summary

Got a question about how sunburst charts work? We are happy to help. Email support@zingchart.com or start a chat right here on this page for help.