8.17.3.1 IfcPhysicalComplexQuantity

8.17.3.1.1 Semantic definition

The complex physical quantity, IfcPhysicalComplexQuantity, is an entity that holds a set of single quantity measure value (as defined at the subtypes of IfcPhysicalSimpleQuantity), that all apply to a given component or aspect of the element.

A section "Quantity Use Definition" at individual entities as subtypes of IfcBuiltElement gives guidance to the usage of the Name and Discrimination attribute to characterize the complex quantities.

8.17.3.1.2 Entity inheritance

8.17.3.1.3 Attributes

#	Attribute	Type	Description
IfcPhysicalQuantity (4)
1	Name	IfcLabel	Name of the element quantity or measure. The name attribute has to be made recognizable by further agreements.
2	Description	OPTIONAL IfcText	Further explanation that might be given to the quantity.
	HasExternalReferences	SET [0:?] OF IfcExternalReferenceRelationship FOR RelatedResourceObjects	Reference to an external reference, e.g. library, classification, or document information, that is associated to the quantity. IFC4-CHANGE New inverse attribute.
	PartOfComplex	SET [0:1] OF IfcPhysicalComplexQuantity FOR HasQuantities	Reference to a physical complex quantity in which the physical quantity may be contained.
Click to show 4 hidden inherited attributes
IfcPhysicalComplexQuantity (4)
3	HasQuantities	SET [1:?] OF IfcPhysicalQuantity	Set of physical quantities that are grouped by this complex physical quantity according to a given discrimination.
4	Discrimination	IfcLabel	Identification of the discrimination by which this physical complex property is distinguished. Examples of discriminations are 'layer', 'steel bar diameter', etc.
5	Quality	OPTIONAL IfcLabel	Additional indication of a quality of the quantities that are grouped under this physical complex quantity.
6	Usage	OPTIONAL IfcLabel	Additional indication of a usage type of the quantities that are grouped under this physical complex quantity.

Table 8.17.3.1.A

8.17.3.1.4 Formal propositions

Name	Description
NoSelfReference	The IfcPhysicalComplexQuantity should not reference itself within the list of HasQuantities.
`SIZEOF(QUERY(temp <* HasQuantities \| SELF :=: temp)) = 0`
UniqueQuantityNames	Every individual IfcPhysicalQuantity within the set HasQuantities shall have a unique Name attribute value. HISTORY New rule in IFC4
`IfcUniqueQuantityNames(HasQuantities)`

Table 8.17.3.1.B

8.17.3.1.5 Formal representation

 ENTITY IfcPhysicalComplexQuantity
 SUBTYPE OF (IfcPhysicalQuantity);
	HasQuantities : SET [1:?] OF IfcPhysicalQuantity;
	Discrimination : IfcLabel;
	Quality : OPTIONAL IfcLabel;
	Usage : OPTIONAL IfcLabel;
 WHERE
	NoSelfReference : SIZEOF(QUERY(temp <* HasQuantities | SELF :=: temp)) = 0;
	UniqueQuantityNames : IfcUniqueQuantityNames(HasQuantities);
END_ENTITY;

8.17.3.1.6 References

IfcPhysicalQuantity