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 | - | - | 'rgba(0, 0, 0, 0.1)' |
borderCapStyle | string | - | - | 'butt' |
borderColor | Color | - | - | 'rgba(0, 0, 0, 0.1)' |
borderDash | number[] | - | - | [] |
borderDashOffset | number | - | - | 0.0 |
borderJoinStyle | string | - | - | 'miter' |
borderWidth | number | - | - | 3 |
fill | boolean|string | - | - | true |
label | string | - | - | '' |
lineTension | number | - | - | 0.4 |
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' |
General
Name | Description |
---|---|
label | The label for the dataset which appears in the legend and tooltips. |
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. |
All these values, if undefined
, 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
Unlike other charts, the radar chart has no chart specific options.
Scale Options
The radar chart supports only a single scale. The options for this scale are defined in the scale
property.
options = {
scale: {
// Hides the scale
display: false
}
};
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]
}]
}