IfcPhysicalComplexQuantity

Semantic definitions at the entity

Entity 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.

EXAMPLE: A layered element, like a wall, may have several material layers, each having individual quantities, like footprint area, side area and volume. An instance of IfcPhysicalComplexQuantity would group these individual quantities (given by a subtype of IfcPhysicalSimpleQuantity) and name them according to the material layer name by using the Name attribute. The Discrimination attribute would then be 'layer'.

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

HISTORY New entity in IFC2x2 Addendum 1.

IFC2x2 ADDENDUM 1 CHANGE The entity IfcPhysicalComplexQuantity has been added. Upward compatibility for file based exchange is guaranteed.

Attribute definitions

#	Attribute	Type	Cardinality	Description	G
3	HasQuantities	IfcPhysicalQuantity	S[1:?]	Set of physical quantities that are grouped by this complex physical quantity according to a given discrimination.	X
4	Discrimination	IfcLabel		Identification of the discrimination by which this physical complex property is distinguished. Examples of discriminations are 'layer', 'steel bar diameter', etc.	X
5	Quality	IfcLabel	?	Additional indication of a quality of the quantities that are grouped under this physical complex quantity.	X
6	Usage	IfcLabel	?	Additional indication of a usage type of the quantities that are grouped under this physical complex quantity.	X

Formal Propositions

Rule	Description
NoSelfReference	The IfcPhysicalComplexQuantity should not reference itself within the list of HasQuantities.
UniqueQuantityNames	Every individual IfcPhysicalQuantity within the set HasQuantities shall have a unique Name attribute value. HISTORY New rule in IFC4

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

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

Formal representations

XML Specification

 <xs:element name="IfcPhysicalComplexQuantity" type="ifc:IfcPhysicalComplexQuantity" substitutionGroup="ifc:IfcPhysicalQuantity" nillable="true"/>

 <xs:complexType name="IfcPhysicalComplexQuantity">

  <xs:complexContent>

   <xs:extension base="ifc:IfcPhysicalQuantity">

    <xs:sequence>

     <xs:element name="HasQuantities">

      <xs:complexType>

       <xs:sequence>

        <xs:element ref="ifc:IfcPhysicalQuantity" maxOccurs="unbounded"/>

       </xs:sequence>

       <xs:attribute ref="ifc:itemType" fixed="ifc:IfcPhysicalQuantity"/>

       <xs:attribute ref="ifc:cType" fixed="set"/>

       <xs:attribute ref="ifc:arraySize" use="optional"/>

      </xs:complexType>

     </xs:element>

    </xs:sequence>

    <xs:attribute name="Discrimination" type="ifc:IfcLabel" use="optional"/>

    <xs:attribute name="Quality" type="ifc:IfcLabel" use="optional"/>

    <xs:attribute name="Usage" type="ifc:IfcLabel" use="optional"/>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


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;

 EXPRESS-G diagram

	Komplexe physikalische Größe
	Physical Complex Quantity
	Quantité physique complexe