8.16.3.7 IfcPropertyDependencyRelationship

8.16.3.7.1 Semantic definition

An IfcPropertyDependencyRelationship describes an identified dependency between the value of one property and that of another.

Use Definition

Whilst the IfcPropertyDependencyRelationship may be used to describe the dependency, and it may do so in terms of the expression of how the dependency operates, it is not possible through the current IFC model for the value of the related property to be actually derived from the value of the relating property. The determination of value according to the dependency is required to be performed by an application that can then use the Expression attribute to flag the form of the dependency.

8.16.3.7.2 Entity inheritance

- IfcResourceLevelRelationship

8.16.3.7.3 Attributes

#	Attribute	Type	Description
IfcResourceLevelRelationship (2)
1	Name	OPTIONAL IfcLabel	A name used to identify or qualify the relationship.
2	Description	OPTIONAL IfcText	A description that may apply additional information about the relationship.
Click to show 2 hidden inherited attributes Click to hide 2 inherited attributes
IfcPropertyDependencyRelationship (3)
3	DependingProperty	IfcProperty	The property on which the relationship depends.
4	DependantProperty	IfcProperty	The dependant property.
5	Expression	OPTIONAL IfcText	Expression that further describes the nature of the dependency relation.

Table 8.16.3.7.A

8.16.3.7.4 Formal propositions

Name	Description
NoSelfReference	The DependingProperty shall not point to the same instance as the DependantProperty.
`DependingProperty :<>: DependantProperty`

Table 8.16.3.7.B

8.16.3.7.5 Formal representation

ENTITY IfcPropertyDependencyRelationship
 SUBTYPE OF (IfcResourceLevelRelationship);
	DependingProperty : IfcProperty;
	DependantProperty : IfcProperty;
	Expression : OPTIONAL IfcText;
 WHERE
	NoSelfReference : DependingProperty :<>: DependantProperty;
END_ENTITY;