Radar

Radar

A radar chart is a way of showing multiple data points and the variation between them.

They are often useful for comparing the points of two or more different data sets.

Example Usage

var myRadarChart = new Chart(ctx, {
    type: 'radar',
    data: data,
    options: options
});

Dataset Properties

The radar 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 a line is generally set this way.

Name	Type	Scriptable	Indexable	Default
`backgroundColor`	`Color`	Yes	-	`‘rgba(0, 0, 0, 0.1)’`
`borderCapStyle`	`string`	Yes	-	`‘butt’`
`borderColor`	`Color`	Yes	-	`‘rgba(0, 0, 0, 0.1)’`
`borderDash`	`number[]`	Yes	-	`[]`
`borderDashOffset`	`number`	Yes	-	`0.0`
`borderJoinStyle`	`string`	Yes	-	`‘miter’`
`borderWidth`	`number`	Yes	-	`3`
`hoverBackgroundColor`	`Color`	Yes	-	`undefined`
`hoverBorderCapStyle`	`string`	Yes	-	`undefined`
`hoverBorderColor`	`Color`	Yes	-	`undefined`
`hoverBorderDash`	`number[]`	Yes	-	`undefined`
`hoverBorderDashOffset`	`number`	Yes	-	`undefined`
`hoverBorderJoinStyle`	`string`	Yes	-	`undefined`
`hoverBorderWidth`	`number`	Yes	-	`undefined`
`fill`	`boolean\|string`	Yes	-	`true`
`label`	`string`	-	-	`‘’`
`order`	`number`	-	-	`0`
`lineTension`	`number`	-	-	`0`
`pointBackgroundColor`	`Color`	Yes	Yes	`‘rgba(0, 0, 0, 0.1)’`
`pointBorderColor`	`Color`	Yes	Yes	`‘rgba(0, 0, 0, 0.1)’`
`pointBorderWidth`	`number`	Yes	Yes	`1`
`pointHitRadius`	`number`	Yes	Yes	`1`
`pointHoverBackgroundColor`	`Color`	Yes	Yes	`undefined`
`pointHoverBorderColor`	`Color`	Yes	Yes	`undefined`
`pointHoverBorderWidth`	`number`	Yes	Yes	`1`
`pointHoverRadius`	`number`	Yes	Yes	`4`
`pointRadius`	`number`	Yes	Yes	`3`
`pointRotation`	`number`	Yes	Yes	`0`
`pointStyle`	`string\|Image`	Yes	Yes	`‘circle’`
`spanGaps`	`boolean`	-	-	`undefined`

General

Name	Description
`label`	The label for the dataset which appears in the legend and tooltips.
`order`	The drawing order of dataset.

Point Styling

The style of each point can be controlled with the following properties:

Name	Description
`pointBackgroundColor`	The fill color for points.
`pointBorderColor`	The border color for points.
`pointBorderWidth`	The width of the point border in pixels.
`pointHitRadius`	The pixel size of the non-displayed point that reacts to mouse events.
`pointRadius`	The radius of the point shape. If set to 0, the point is not rendered.
`pointRotation`	The rotation of the point in degrees.
`pointStyle`	Style of the point. more…

All these values, if undefined, fallback first to the dataset options then to the associated elements.point.* options.

Line Styling

The style of the line can be controlled with the following properties:

Name	Description
`backgroundColor`	The line fill color.
`borderCapStyle`	Cap style of the line. See MDN.
`borderColor`	The line color.
`borderDash`	Length and spacing of dashes. See MDN.
`borderDashOffset`	Offset for line dashes. See MDN.
`borderJoinStyle`	Line joint style. See MDN.
`borderWidth`	The line width (in pixels).
`fill`	How to fill the area under the line. See area charts.
`lineTension`	Bezier curve tension of the line. Set to 0 to draw straightlines.
`spanGaps`	If true, lines will be drawn between points with no or null data. If false, points with `NaN` data will create a break in the line.

If the value is undefined, spanGaps fallback to the associated chart configuration options. The rest of the values fallback to the associated elements.line.* options.

Interactions

The interaction with each point can be controlled with the following properties:

Name	Description
`pointHoverBackgroundColor`	Point background color when hovered.
`pointHoverBorderColor`	Point border color when hovered.
`pointHoverBorderWidth`	Border width of point when hovered.
`pointHoverRadius`	The radius of the point when hovered.

Configuration Options

The radar chart defines the following configuration options. These options are merged with the global chart configuration options, Chart.defaults.global, to form the options passed to the chart.

Name	Type	Default	Description
`spanGaps`	`boolean`	`false`	If false, NaN data causes a break in the line.

Scale Options

The radar chart supports only a single scale. The options for this scale are defined in the scale property. The options for this scale are defined in the scale property, which can be referenced from the Linear Radial Axis page.

options = {
    scale: {
        angleLines: {
            display: false
        },
        ticks: {
            suggestedMin: 50,
            suggestedMax: 100
        }
    }
};

Default Options

It is common to want to apply a configuration setting to all created radar charts. The global radar chart settings are stored in Chart.defaults.radar. Changing the global options only affects charts created after the change. Existing charts are not changed.

Data Structure

The data property of a dataset for a radar chart is specified as an array of numbers. Each point in the data array corresponds to the label at the same index.

data: [20, 10]

For a radar chart, to provide context of what each point means, we include an array of strings that show around each point in the chart.

data: {
    labels: ['Running', 'Swimming', 'Eating', 'Cycling'],
    datasets: [{
        data: [20, 10, 4, 2]
    }]
}