Coordinate Map

A Coordinate Map visualization displays a geographic area overlaid with circles keyed to the data determined by the buckets you specify.

By default, Siren Investigate uses a demonstration Siren tilemap server Open Street Maps service to display map tiles. This server has limited features and you should update the tilemap settings to another tilemap provider that you have configured, especially in a production setting. To use other tile service providers, configure the tilemap settings in investigate.yml.

Configuration

Configuring external tilemap providers

You can use existing free or paid tilemap providers or build and serve your own tilemap tiles.

After you have setup your own tilemap provider, configure these tilemap settings in investigate.yml to have map visualizations render these tiles.

For example, to use an OpenStreetMap default provider, the configuration YAML settings would look like:

tilemap:
  url: 'https://{s}.tile.openstreetmap.org/{z}/{x}/{y}.png'
  options:
    attribution: '© [OpenStreetMap]("http://www.openstreetmap.org/copyright")'
    subdomains:
      - a

The Data Tab

Metrics

The default metrics aggregation for a coordinate map is the Count aggregation. You can select any of the following aggregations as the metrics aggregation:

  • Count

  • Average

  • Sum

  • Min

  • Max

  • Unique Count

For more information, see Y-axis aggregations.

Enter a string in the Custom Label field to change the display label.

Buckets

Coordinate maps use the geohash aggregation. Select a field, typically coordinates, from the box.

  • The Change precision on map zoom check box is selected by default. Clear the check box to switch off this behavior. The Precision slider determines the granularity of the results displayed on the map. See the documentation for the geohash grid aggregation for details on the area specified by each precision level.

Higher precision increases memory usage for the browser displaying Siren Investigate as well as for the underlying Elasticsearch cluster.
  • The place markers off grid (use geocentroid) box is checked by default. When this box is checked, the markers are placed in the center of all the documents in that bucket. When cleared, the markers are placed in the center of the geohash grid cell. Leaving this checked generally results in a more accurate visualization.

You can customize your visualization. For more information, see Customizing visualizations.

Options

Map type

Select one of the following options from the box.

Scaled Circle Markers

Scale the size of the markers based on the metric aggregation’s value.

Shaded Circle Markers

Displays the markers with different shades based on the metric aggregation’s value.

Shaded Geohash Grid

Displays the rectangular cells of the geohash grid instead of circular markers, with different shades based on the metric aggregation’s value.

Heatmap

A heat map applies blurring to the circle markers and applies shading based on the amount of overlap. Heatmaps have the following options: +

  • Radius: Sets the size of the individual heatmap dots.

  • Blur: Sets the amount of blurring for the heatmap dots.

  • Maximum zoom: Tilemaps in Siren Investigate support 18 zoom levels. This slider defines the maximum zoom level at which the heatmap dots appear at full intensity.

  • Minimum opacity: Sets the opacity cutoff for the dots.

  • Show Tooltip: Check this box to have a tooltip with the values for a given dot when the cursor is on that dot.

Desaturate map tiles

Desaturates the map’s color to make the markers stand out more clearly.

WMS compliant map server

Check this box to enable the use of a third-party mapping service that complies with the Web Map Service (WMS) standard. Specify the following elements: +

  • WMS url: The URL for the WMS map service.

  • WMS layers: A comma-separated list of the layers to use in this visualization. Each map server provides its own list of layers.

  • WMS version: The WMS version used by this map service.

  • WMS format: The image format used by this map service. The two most common formats are image/png and image/jpeg.

  • WMS attribution: An optional, user-defined string that identifies the map source. Maps display the attribution string in the lower right corner.

  • WMS styles: A comma-separated list of the styles to use in this visualization. Each map server provides its own styling options.

After changing options, click Apply changes to update your visualization, or Discard changes to keep your visualization in its current state.

If you need to display custom layers for the Coordinate Map visualization, a geospatial server may provide the solution. See Configuring GeoServer.

Navigating the map

After your tilemap visualization is ready, you can explore the map in several ways:

  • Click and hold anywhere on the map and move the cursor to move the map center. Hold Shift and drag a bounding box across the map to zoom in on the selection.

  • Click Zoom In/Out (image) to change the zoom level manually.

  • Click Fit Data Bounds (image) to automatically crop the map boundaries to the geohash buckets that have at least one result.

  • Click Latitude/Longitude Filter (image), then drag a bounding box across the map, to create a filter for the box coordinates.

Viewing detailed information

For information on displaying the raw data, see Inspecting visualizations.