6.10.2. Symbology

The layer symbology can be changed within the properties of each layer under the Symbology tab. Depending on the type of data you want to symbolize, there are various options. For example, layers can be symbolized based on one set of features (Features), categories of attributes based on unique values or unique values using many fields (Categories), or quantities of attributes (Quantities). As an example, we will use the commune_boundary_FR layer and change the symbology so that each commune is represented by a different colour.

To change symbology to represent unique features:

  1. Right-click commune_boundary_FR layer.
  2. Select Properties.
  3. Select Symbology.
  4. Select Categories.
  5. Select Unique values.
  6. For the Value Field choose the attribute to be symbolized. In this case it is GEMNAME.
  7. Click the Add All Values button.
  8. Click OK.

The results show each commune represented by a different colour (Fig. 62).

Fig. 62. The results of symbolizing a layer based on the values of an attribute. In this example, each colour represents a different commune around Fribourg. Reproduced with permission of Swisstopo (BA13016).