Pattern themes allow you to easily create a map showing locations using either an alphabetical letter or a number, with a legend that automatically categorizes such locations by name. The following steps walk through setting this up:
- Make the point layer that contains the data you want to map the working layer.
- Choose Map>Thematic Mapping>Multiple Symbol from the menu; choose the Field you want displayed in the legend; choose List of Values as the method, choose a number of classes, and click the Style tab. Click Next >> on the style tab to list the alphabetical class.
- Click OK. Each location is represented as a letter in the map, which is also listed in the legend with the corresponding feature name/identifier.