The Map Marker Series visualises data for geographic points, with the ability to vary the size to represent data values.
 Simple Map Markers Copy Link  
To create a Map Marker Series, use the map-marker series type and provide data and topology. These can be provided in either the chart or series objects.
A Map Marker Series should be combined with a Map Shape Background Series.
data: data,
topology: topology,
series: [
    // ...
    {
        type: 'map-marker',
        idKey: 'name',
    },
]
In this configuration:
- The topologyanddataare provided once on the chart level.
- idKeydefines the property key in the data that will be matched against the property value in the topology. See Connecting Data to Topology for more details.
- The map-shape-backgroundseries has its topology defined on the series level.
- The map-shape-backgroundseries is rendered behind themap-markerseries due to their order in the series array.
 Map Marker Position from Data Copy Link  
Instead of using a topology file, the Map Marker Series can use geographic data from within the data. This is best suited for data containing latitude and longitude coordinates such as crime data.
data: data,
series: [
    // ...
    {
        type: 'map-marker',
        latitudeKey: 'lat',
        longitudeKey: 'lon',
    },
]
In this configuration:
- No topologyis required for themap-markerseries.
- latitudeKeyand- longitudeKeyrefer to fields in the provided data, and are used to position the marker.
 Proportional Marker Size Copy Link  
To vary the size of the marker to denote the magnitude of the data values use sizeKey, size and maxSize.
{
    series: [
        // ...
        {
            type: 'map-marker',
            latitudeKey: 'lat',
            longitudeKey: 'lon',
            sizeKey: 'count',
            sizeName: 'Count',
            size: 3,
            maxSize: 50,
        },
    ],
}
In this configuration:
- sizeKeyprovides the numerical values determining the size of each marker.
- sizeNameis optional and configures the display name reflected in Tooltips.
- sizeprovides the size of the marker for the smallest data point.
- maxSizeprovides the size for the largest data point.
 Customisation Copy Link  
It is possible to customise the fill, stroke and shape of the markers, as well as to add labels. See the API Reference for more details.