Here the theme is divided into five classes (Sea-level, small lake, larger lakes, Forestry and glaciers), each of these categories has its own fill color (Fill color), glaciers also has a phantom perimeter / outline (Outline Color, Width and Pattern ).
To set which surfaces that should belong to the different classes, is used in this example a combination of Classitem and putting both columns and values in the expression (Expression). On Classitem its been selected column “objtype” and that the simple classes (Sea-level, Forest, glaciers) is set expressions (Expression) such as “Sea-level,” those that can be set by using only value of a column, and type expression (Expression type). In this case, use the type “String”.
The values set are obtained from the characteristic column “objtype” to relevant data sets.
For the two classes for lakes (Small lake and Larger Lakes), we use the type (Expression type) “Logical expression”. It allows us to put together more sophisticated expressions (Expression). Example:
- Small lakes: ‘[objtype]’=’Innsjø’ AND [shape_area] < 100000000
- Larger lakes: ‘[objtype]’=’Innsjø’ AND [shape_area] > 100000000
Indicates both columns, comparison operators and values. Around columns used parenthesis “”. If the column is of type text, both kolonnnavn by square brackets and also the values enclosed in single apostrophes.
In the example above used the comparative =, <and>.
Example on legend
Example on map