Add an Expression Operator node (
) under
Definitions>Variable Utilities (if
Group by Type is active; otherwise, directly under
Definitions) to define an operator that evaluates parameterized expressions on specified selections. You add it by right-clicking the
Definitions node and choosing
Variable Utilities>Expression Operator or by right-clicking the
Variable Utilities node and choosing
Expression Operator.
The Expression Operator node specifies an operator name, formal argument names and dimensions, a default expression, and a selection where the operator will be defined. Alternate expressions can be defined on subsets of the operator selection (also of lower dimensions) using
Operator Contribution subnodes. The defining expressions can in addition to the formal arguments contain any variable and operator names that can be evaluated on the corresponding selection. When the operator is used in a model, different operator expressions may be evaluated depending on where the operator is used, and variables in the expressions may evaluate differently depending on their selections.
In this section, define the selection for the expression operator. By default, the Geometry entity level is set to
Entire model, meaning that the operator will be available globally.
In the Expression field, enter the default expression for the operator. This expression is the one that will be used on the parts of the
Expression Operator node’s selection that have
not been overridden by an
Operator Contribution subnode. The expression may contain both the specified formal argument names and other variables, which are assumed to exist on the selection. The output unit of the operator is derived from the default expression.
In the table of arguments, enter the name of each formal argument in the Argument column and its expected dimensions, in the form of a unit expression, in the
Dimensions column. The dimensions are used when deriving the operator’s dimensions and for checking unit consistency when the operator is used in expressions.