IFC 4.3.x development

8.16.3.7 IfcPropertyDependencyRelationship

Change log

IFC4

additionswhere_rulesNoSelfReference
deletionsattributes Description
deletionsattributes Name
deletionswhere_rulesWR1

8.16.3.7.1 Semantic definitions at the entity

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

HISTORY  New entity in IFC2x2

IFC4 CHANGE  Made subtype of IfcResourceLevelRelationship (attribute order changed).

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.

8.16.3.7.1 Attributes

#Attribute Type Description
IfcResourceLevelRelationship
1Name OPTIONAL IfcLabelA name used to identify or qualify the relationship.
2Description OPTIONAL IfcText A description that may apply additional information about the relationship.
IfcPropertyDependencyRelationship
3DependingPropertyIfcProperty The property on which the relationship depends.
4DependantPropertyIfcProperty The dependant property.
5Expression OPTIONAL IfcText Expression that further describes the nature of the dependency relation.

8.16.3.7.2 Entity inheritance

dot_inheritance IfcPropertyDependencyRelationship IfcPropertyDependencyRelationship IfcResourceLevelRelationship IfcResourceLevelRelationship IfcPropertyDependencyRelationship->IfcResourceLevelRelationship IfcResourceLevelRelationship_children 8 more... IfcResourceLevelRelationship_children->IfcResourceLevelRelationship

8.16.3.7.3 Formal representations

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