Using expressions in numeric or fixed-value properties
For styling properties which usually have a fixed type
of value (for example, numeric) or a fixed list of possible values
(for example, true and false), you cannot enter a data model reference or expression directly.
Instead, you must use the right-click menu.
In the ArizonaLogical example,
select the link rule.
Click the Width tab in the Styling Customizer.
The styling properties in this tab are numeric.
Increase the value in the Line width
max. field to 50.
Click in the Line width field.
Clear the value.
Right-click and select Enter an Expression.
Enter @Traffic.
Press Enter.
Click in the canvas to see the result better.
The line widths reflect the volume of traffic on the
link, see the following figure.
Numeric data model attribute value used in a diagram
If the thickness of the lines is not sufficient, try
entering @|@Traffic*2 instead.