--- /dev/null
+---
+title: Radar Chart
+anchor: radar-chart
+---
+
+###Introduction
+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.
+
+<div class="canvas-holder">
+ <canvas width="250" height="125"></canvas>
+</div>
+
+###Example usage
+
+```javascript
+var myRadarChart = new Chart(ctx).Radar(data, options);
+```
+
+###Data structure
+```javascript
+var data = {
+ labels: ["Eating", "Drinking", "Sleeping", "Designing", "Coding", "Cycling", "Running"],
+ datasets: [
+ {
+ label: "My First dataset",
+ fillColor: "rgba(220,220,220,0.2)",
+ strokeColor: "rgba(220,220,220,1)",
+ pointColor: "rgba(220,220,220,1)",
+ pointStrokeColor: "#fff",
+ pointHighlightFill: "#fff",
+ pointHighlightStroke: "rgba(220,220,220,1)",
+ data: [65, 59, 90, 81, 56, 55, 40]
+ },
+ {
+ label: "My Second dataset",
+ fillColor: "rgba(151,187,205,0.2)",
+ strokeColor: "rgba(151,187,205,1)",
+ pointColor: "rgba(151,187,205,1)",
+ pointStrokeColor: "#fff",
+ pointHighlightFill: "#fff",
+ pointHighlightStroke: "rgba(151,187,205,1)",
+ data: [28, 48, 40, 19, 96, 27, 100]
+ }
+ ]
+};
+```
+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.
+For the radar chart data, we have an array of datasets. Each of these is an object, with a fill colour, a stroke colour, a colour for the fill of each point, and a colour for the stroke of each point. We also have an array of data values.
+
+The label key on each dataset is optional, and can be used when generating a scale for the chart.
+
+### Chart options
+
+These are the customisation options specific to Radar charts. These options are merged with the [global chart configuration options](#getting-started-global-chart-configuration), and form the options of the chart.
+
+
+```javascript
+{
+ //Boolean - Whether to show lines for each scale point
+ scaleShowLine : true,
+
+ //Boolean - Whether we show the angle lines out of the radar
+ angleShowLineOut : true,
+
+ //Boolean - Whether to show labels on the scale
+ scaleShowLabels : false,
+
+ // Boolean - Whether the scale should begin at zero
+ scaleBeginAtZero : true,
+
+ //String - Colour of the angle line
+ angleLineColor : "rgba(0,0,0,.1)",
+
+ //Number - Pixel width of the angle line
+ angleLineWidth : 1,
+
+ //String - Point label font declaration
+ pointLabelFontFamily : "'Arial'",
+
+ //String - Point label font weight
+ pointLabelFontStyle : "normal",
+
+ //Number - Point label font size in pixels
+ pointLabelFontSize : 10,
+
+ //String - Point label font colour
+ pointLabelFontColor : "#666",
+
+ //Boolean - Whether to show a dot for each point
+ pointDot : true,
+
+ //Number - Radius of each point dot in pixels
+ pointDotRadius : 3,
+
+ //Number - Pixel width of point dot stroke
+ pointDotStrokeWidth : 1,
+
+ //Number - amount extra to add to the radius to cater for hit detection outside the drawn point
+ pointHitDetectionRadius : 20,
+
+ //Boolean - Whether to show a stroke for datasets
+ datasetStroke : true,
+
+ //Number - Pixel width of dataset stroke
+ datasetStrokeWidth : 2,
+
+ //Boolean - Whether to fill the dataset with a colour
+ datasetFill : true,
+ {% raw %}
+ //String - A legend template
+ legendTemplate : "<ul class=\"<%=name.toLowerCase()%>-legend\"><% for (var i=0; i<datasets.length; i++){%><li><span style=\"background-color:<%=datasets[i].strokeColor%>\"></span><%if(datasets[i].label){%><%=datasets[i].label%><%}%></li><%}%></ul>"
+ {% endraw %}
+}
+```
+
+
+You can override these for your `Chart` instance by passing a second argument into the `Radar` method as an object with the keys you want to override.
+
+For example, we could have a radar chart without a point for each on piece of data by doing the following:
+
+```javascript
+new Chart(ctx).Radar(data, {
+ pointDot: false
+});
+// This will create a chart with all of the default options, merged from the global config,
+// and the Bar chart defaults but this particular instance will have `pointDot` set to false.
+```
+
+We can also change these defaults values for each Radar type that is created, this object is available at `Chart.defaults.Radar`.
+
+
+### Prototype methods
+
+#### .getPointsAtEvent( event )
+
+Calling `getPointsAtEvent(event)` on your Chart instance passing an argument of an event, or jQuery event, will return the point elements that are at that the same position of that event.
+
+```javascript
+canvas.onclick = function(evt){
+ var activePoints = myRadarChart.getPointsAtEvent(evt);
+ // => activePoints is an array of points on the canvas that are at the same position as the click event.
+};
+```
+
+This functionality may be useful for implementing DOM based tooltips, or triggering custom behaviour in your application.
+
+#### .update( )
+
+Calling `update()` on your Chart instance will re-render the chart with any updated values, allowing you to edit the value of multiple existing points, then render those in one animated render loop.
+
+```javascript
+myRadarChart.datasets[0].points[2].value = 50;
+// Would update the first dataset's value of 'Sleeping' to be 50
+myRadarChart.update();
+// Calling update now animates the position of Sleeping from 90 to 50.
+```
+
+#### .addData( valuesArray, label )
+
+Calling `addData(valuesArray, label)` on your Chart instance passing an array of values for each dataset, along with a label for those points.
+
+```javascript
+// The values array passed into addData should be one for each dataset in the chart
+myRadarChart.addData([40, 60], "Dancing");
+// The new data will now animate at the end of the chart.
+```
+
+#### .removeData( )
+
+Calling `removeData()` on your Chart instance will remove the first value for all datasets on the chart.
+
+```javascript
+myRadarChart.removeData();
+// Other points will now animate to their correct positions.
+```
\ No newline at end of file
projects / soho-sigint.git / blobdiff