The Map Marker Series visualises data for geographic points, with the ability to vary the size to represent data values.
Simple Map Markers
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
topology
anddata
are provided once on the chart level. idKey
defines 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-background
series has its topology defined on the series level. - The
map-shape-background
series is rendered behind themap-marker
series due to their order in the series array.
Map Marker Position from Data
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 logitute coordinates such as crime data.
data: data,
series: [
// ...
{
type: 'map-marker',
latitudeKey: 'lat',
longitudeKey: 'lon',
},
],
In this configuration:
- No
topology
is required for themap-marker
series. latitudeKey
andlongitudeKey
refer to fields in the provided data, and are used to position the marker.
Proportional Marker Size
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:
sizeKey
provides the numerical values determining the size of each marker.sizeName
is optional and configures the display name reflected in Tooltips.size
provides the size of the marker for the smallest data point.maxSize
provides the size for the largest data point.
Customisation
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.