Using alphabetic values in interactive maps

CDP Data Visualization interactive map visuals support both numeric and non-numeric values on the Color shelf. As a result, aspects of named categories can be viewed simultaneously on the same visual as a distinct series.

We are using truck movement data to demonstrate how to plot incident counts for several drivers, and differentiate them by the color.

Select the appropriate dataset, and create a new dashboard; in the dashboard, open the default visual and change the visual type to Interactive Map.
Enable the Circles, as described in Displaying circles: click the Settings menu, select Circles, and then select the Enable Circles option.
Similarly, enable both the area and color legends of the Circles option by selecting the Add Circle Area Legend and Add Circle Color Legend options.
[Optional] Disable all the other layers: heatmap, cluster, marker, and route.
Populate the shelves from the available fields (Dimensions, Measures, and so on) in the Data menu.
1. Geo Shelf - Under Measures, select latitude and longitude, and add them to the Geo shelf.
  
  If your longitude and latitude measurements are not automatically recognized (appear with a (globe) icon on the Geo shelf), cast them to the appropriate Geo Type. Click the filed on the shelf; in the Field Properties menu, select Change Type, and then select Latitude or Longitude, as appropriate. See Change type and Geo data type.
2. Measures Shelf - Under Measures, select eventtype and place it on the measures shelf.
  
  Change the aggregation function to count(), and Alias the field as # Incidents.
3. Colors Shelf - Under Measures, select drivername, and place it on the Colors shelf.
  
  You may need to remove the default field aggregation from the field on the shelf.
  
  Alias the field as Driver.
4. Filters Shelf - Add the field eventtype to this shelf, and select the single value 'Overspeed'.
  
  Add the field drivername to the filters shelf, and select a small number of drivers to see details.
[Optional] Change the color palette to ensure that the routes stand out sufficiently over the regular features of the map.

Click Colors, and select an appropriate palette.
Click Refresh Visual.
The visual appears. Note that the colors are defined by the names of the drivers, which are non-numeric.
Change the title of the visual, and Save it.