IfcPropertyEnumeration

Semantic definitions at the entity

Entity definition

IfcPropertyEnumeration is a collection of simple or measure values that define a prescribed set of alternatives from which 'enumeration values' are selected. This enables inclusion of enumeration values in property sets. IfcPropertyEnumeration provides a name for the enumeration as well as a list of unique (numeric or descriptive) values (that may have a measure type assigned). The entity defines the list of potential enumerators to be exchanged together (or separately) with properties of type IfcPropertyEnumeratedValue that selects their actual property values from this enumeration.

The unit is handled by the Unit attribute, see Table 346 for an example of a unitless property enumeration:

If the Unit attribute is not given, than the unit is already implied by the type of IfcMeasureValue or IfcDerivedMeasureValue. The associated unit can be found at the IfcUnitAssignment globally defined at the project level (IfcProject.UnitsInContext).
If the Unit attribute is given, the unit assigned by the unit attribute overrides the globally assigned unit.

Name	EnumerationValues	Type (through IfcValue)	Unit
PEnum_DamperBladeAction	Parallel	IfcLabel	-
	Opposed	IfcLabel
	Other	IfcLabel
	Unset	IfcLabel

Table 346 — Property enumeration with values, measure types and units

HISTORY New entity in IFC2.0, capabilities enhanced in IFC2x.

IFC2x CHANGE Entity has been renamed from IfcEnumeration

Attribute definitions

#	Attribute	Type	Cardinality	Description	R
1	Name	IfcLabel		Name of this enumeration.	X
2	EnumerationValues	IfcValue	L[1:?]	List of values that form the enumeration.	X
3	Unit	-		This attribute is out of scope for this model view definition and shall not be set.

Formal Propositions

Rule	Description
WR01	All values within the list of EnumerationValues shall be of the same measure type.

#	Attribute	Type	Cardinality	Description	R
IfcPropertyAbstraction
IfcPropertyEnumeration
1	Name	IfcLabel		Name of this enumeration.	X
2	EnumerationValues	IfcValue	L[1:?]	List of values that form the enumeration.	X
3	Unit	-		This attribute is out of scope for this model view definition and shall not be set.

Formal representations

XML Specification

 <xs:element name="IfcPropertyEnumeration" type="ifc:IfcPropertyEnumeration" substitutionGroup="ifc:IfcPropertyAbstraction" nillable="true"/>

 <xs:complexType name="IfcPropertyEnumeration">

  <xs:complexContent>

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

    <xs:sequence>

     <xs:element name="EnumerationValues">

      <xs:complexType>

       <xs:group ref="ifc:IfcValue" maxOccurs="unbounded"/>

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

       <xs:attribute ref="ifc:cType" fixed="list-unique"/>

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

      </xs:complexType>

     </xs:element>

    </xs:sequence>

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

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcPropertyEnumeration

 SUBTYPE OF (IfcPropertyAbstraction);

  Name : IfcLabel;

  EnumerationValues : LIST [1:?] OF UNIQUE IfcValue;

  Unit : OPTIONAL IfcStrippedOptional;

 UNIQUE

  UR1 : Name;
 WHERE

  WR01 : SIZEOF(QUERY(temp <* SELF.EnumerationValues | 

  NOT(TYPEOF(SELF.EnumerationValues[1]) = TYPEOF(temp))

  )) = 0;
END_ENTITY;

 EXPRESS-G diagram

	Merkmal - Aufzählung
	Property Enumeration
	Propriété à valeurs énumérées

IfcPropertyEnumeration

Semantic definitions at the entity

Inherited definitions from supertypes

Formal representations