This tutorial demonstrates how to use expressions, which are mathematical formulas that modify a property within a label style.
You use text, lines, and block data components to present static data in a label style. Expressions modify the data in the standard label style components. For example, in the Layout tab of the Label Style Composer dialog box, you can insert an expression in place of a static value when determining the text height of a label. This expression could increase the text height of a spot elevation label to coincide with the elevation height.
In this tutorial, you will update an existing label style to add an expression that displays magnetic compass directions of the alignment at each geometry point.