Named Expressions

Named expressions can contain any combination of scalar, vector, or geometry functions. When you plot a field overlay or create a report based on a named expression, only corresponding quantities are available.

For example, if you select a point for the Geometry and a Category that is a named expression based on the point (or other scalar, non-3D value), then the Quantity list only lists expressions that returns a single scalar value. If you have added named expressions that take the magnitude of the ScalarX(), ScalarY(), or ScalarZ() of a vector point value, then you can create output variables for those expressions only in this case.

Named expressions can be plotted in the following three ways:

• To create a field overlay of a named expression, the expression must be a real value (scalar or vector) that has values everywhere in space (or at least on every point in the geometry you plan to use for the field overlay).

• To create a 2D report from a named expression that evaluates in the Fields Calculator as a single scalar value, the expression must result in a single-valued, real, scalar value. A single-valued item could be the value on a single point in space or the result of a function that returns a single value (such as an integration, max/value, min/value, or other function).

• To create a 2D report from a named expression that is evaluated (in the Fields Calculator) along a polyline, the expression must be a real scalar that has values everywhere in space (or at least everywhere on the line object you want to use to sample the values). Named expressions can be created in the Fields Calculator.