IFC 4.3.0.0 (IFC4X3) final

8.17.3.3 IfcPhysicalSimpleQuantity

ABSTRACT This definition may not be instantiated

8.17.3.3.1 Semantic definition

The physical quantity, IfcPhysicalSimpleQuantity, is an entity that holds a single quantity measure value (as defined at the subtypes of IfcPhysicalSimpleQuantity) together with a semantic definition of the usage for the measure value.

A section "Quantity Use Definition" at individual entities as subtypes of IfcBuildingElement gives guidance to the usage of the Name attribute to characterize the individual quantities. If the Unit attribute is given, the value attribute (introduced at the level of subtypes of IfcPhysicalSimpleQuantity) are given as quantities of this unit, otherwise the global unit definitions (given by IfcUnitAssignment) are used.

8.17.3.3.2 Entity inheritance

8.17.3.3.3 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.

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 Click to hide 4 inherited attributes
IfcPhysicalSimpleQuantity (1)
3 Unit OPTIONAL IfcNamedUnit

Optional assignment of a unit. If no unit is given, then the global unit assignment, as established at the IfcProject, applies to the quantity measures.

Table 8.17.3.3.A

8.17.3.3.4 Formal representation

ENTITY IfcPhysicalSimpleQuantity
 ABSTRACT SUPERTYPE OF (ONEOF
	(IfcQuantityArea
	,IfcQuantityCount
	,IfcQuantityLength
	,IfcQuantityNumber
	,IfcQuantityTime
	,IfcQuantityVolume
	,IfcQuantityWeight))
 SUBTYPE OF (IfcPhysicalQuantity);
	Unit : OPTIONAL IfcNamedUnit;
END_ENTITY;

8.17.3.3.5 References