Chart.js/docs/charts/bubble.md

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Bubble Chart

A bubble chart is used to display three dimensions of data at the same time. The location of the bubble is determined by the first two dimensions and the corresponding horizontal and vertical axes. The third dimension is represented by the size of the individual bubbles.

{% chartjs %} { "type": "bubble", "data": { "datasets": [{ "label": "First Dataset", "data": [{ "x": 20, "y": 30, "r": 15 }, { "x": 40, "y": 10, "r": 10 }], "backgroundColor": "rgb(255, 99, 132)" }] }, } {% endchartjs %}

Example Usage

// For a bubble chart
var myBubbleChart = new Chart(ctx,{
    type: 'bubble',
    data: data,
    options: options
});

Dataset Properties

The bubble chart allows a number of properties to be specified for each dataset. These are used to set display properties for a specific dataset. For example, the colour of the bubbles is generally set this way.

All properties, except label can be specified as an array. If these are set to an array value, the first value applies to the first bubble in the dataset, the second value to the second bubble, and so on.

Name Type Description
label String The label for the dataset which appears in the legend and tooltips.
backgroundColor Color/Color[] The fill color for bubbles.
borderColor Color/Color[] The border color for bubbles.
borderWidth Number/Number[] The width of the point bubbles in pixels.
hoverBackgroundColor Color/Color[] Bubble background color when hovered.
hoverBorderColor Color/Color[] Bubble border color when hovered.
hoverBorderWidth Number/Number[] Border width of point when hovered.
hoverRadius Number/Number[] Additional radius to add to data radius on hover.

Config Options

The bubble chart has no unique configuration options. To configure options common to all of the bubbles, the point element options are used.

Default Options

We can also change the default values for the Bubble chart type. Doing so will give all bubble charts created after this point the new defaults. The default configuration for the bubble chart can be accessed at Chart.defaults.bubble.

Data Structure

For a bubble chart, datasets need to contain an array of data points. Each point must implement the bubble data object interface.

Bubble Data Object

Data for the bubble chart is passed in the form of an object. The object must implement the following interface. It is important to note that the radius property, r is not scaled by the chart. It is the raw radius in pixels of the bubble that is drawn on the canvas.

{
    // X Value
    x: <Number>,

    // Y Value
    y: <Number>,

    // Radius of bubble. This is not scaled.
    r: <Number>
}