IfcPropertyEnumeratedValue

Natural language names
Merkmal mit Aufzählungswert
Property Enumerated Value
Propriété à valeur issue d'un énumération
Change log
ItemSPFXMLChangeDescription
IFC2x3 to IFC4
    IfcPropertyEnumeratedValue
      EnumerationValuesMODIFIEDInstantiation changed to OPTIONAL.
IFC4 Addendum 1
    IfcPropertyEnumeratedValue
      HasConstraintsADDED
      HasApprovalsADDED
Semantic definitions at the entity
Entity definition

A property with an enumerated value, IfcPropertyEnumeratedValue, defines a property object which has a value assigned that is chosen from an enumeration. It defines a property - value combination for which the property Name, an optional Description, the optional EnumerationValues with measure type and optionally an Unit is given.

NOTE  Multiple choices from the property enumeration are supported.

The unit is handled by the Unit attribute, see Table 701 for an example of a enumerated property:

More precisely: The IfcPropertyEnumeratedValue defines a property, which value is selected from a defined list of enumerators. The enumerators are stored in a dynamic enumeration of values including the type information from IfcValue (see IfcPropertyEnumeration). This enables applications to use an enumeration value as a property within a property set (IfcPropertySet) including the allowed list of values. 

NOTE  An IfcPropertyEnumeratedValue may be exchanged with no values assigned yet. In this case the EnumerationValues are set to NIL.

 

Name Value
(EnumerationValue)
Type
(through IfcValue)
IfcPropertyEnumeration
(Name)
BladeAction Opposed IfcLabel DamperBladeActionEnum
BladeAction Parallel IfcLabel DamperBladeActionEnum

Table 701 — Enumerated property with values, measure types and units

 

The IfcPropertyEnumeratedValue refers to an IfcPropertyEnumeration, see Table 702 for an example:

Name EnumerationValues Type
(through IfcValue)
Unit
DamperBladeActionEnum (Parallel, Opposed, Other, Unset) IfcString -

Table 702 — Property enumeration with enumerators

It is not mandatory to use an instance of IfcPropertyEnumeration to hold the applicable values for IfcPropertyEnumeratedValue, however this is the preferred way. A single instance of IfcPropertyEnumeration can be referenced by multiple instances of IfcPropertyEnumeratedValue.

HISTORY  New entity in IFC2.0.
IFC2x CHANGE  Entity has been renamed from IfcEnumeratedProperty
IFC4 CHANGE  Attribute EnumerationValues has been made OPTIONAL with upward compatibility for file based exchange.
Attribute definitions
#AttributeTypeCardinalityDescription G
3EnumerationValuesIfcValue? L[1:?] Enumeration values, which shall be listed in the referenced IfcPropertyEnumeration, if such a reference is provided.
IFC4 CHANGE  The attribute has been made optional with upward compatibility for file based exchange.
X
4EnumerationReferenceIfcPropertyEnumeration? Enumeration from which a enumeration value has been selected. The referenced enumeration also establishes the unit of the enumeration value.X
Formal Propositions
RuleDescription
WR21Each value within the list of EnumerationValues shall be a member of the list of EnumerationValues at the referenced IfcPropertyEnumeration (provided that both, the EnumerationValues and EnumerationReference, are asserted).
Inherited definitions from supertypes
Entity inheritance IfcSimpleProperty IfcProperty IfcPropertyAbstraction
Attribute inheritance
#AttributeTypeCardinalityDescriptionG
IfcPropertyAbstraction
HasExternalReferencesIfcExternalReferenceRelationship
@RelatedResourceObjects
S[0:?]Reference to an external reference, e.g. library, classification, or document information, that is associated to the property definition.
IFC4 CHANGE New inverse attribute.
X
IfcProperty
1NameIfcIdentifier Name for this property. This label is the significant name string that defines the semantic meaning for the property.X
2DescriptionIfcText? Informative text to explain the property.X
PartOfPsetIfcPropertySet
@HasProperties
S[0:?]Reference to the IfcPropertySet by which the IfcProperty is referenced.
IFC4 CHANGE  New inverse attribute to navigate from IfcProperty to IfcPropertySet with upward compatibility for file based exchange.
X
PropertyForDependanceIfcPropertyDependencyRelationship
@DependingProperty
S[0:?]The property on whose value that of another property depends.X
PropertyDependsOnIfcPropertyDependencyRelationship
@DependantProperty
S[0:?]The relating property on which the value of the property depends.X
PartOfComplexIfcComplexProperty
@HasProperties
S[0:?]Reference to the IfcComplexProperty in which the IfcProperty is contained.
IFC4 CHANGE  The cardinality has changed to 0..n to allow reuse of instances of IfcProperty in several IfcComplexProperty with upward compatibility for file based exchange.
X
HasConstraintsIfcResourceConstraintRelationship
@RelatedResourceObjects
? S[0:?]User-defined constraints for the property.X
HasApprovalsIfcResourceApprovalRelationship
@RelatedResourceObjects
? S[0:?]User-defined approvals for the property.X
IfcSimpleProperty
IfcPropertyEnumeratedValue
3EnumerationValuesIfcValue? L[1:?] Enumeration values, which shall be listed in the referenced IfcPropertyEnumeration, if such a reference is provided.
IFC4 CHANGE  The attribute has been made optional with upward compatibility for file based exchange.
X
4EnumerationReferenceIfcPropertyEnumeration? Enumeration from which a enumeration value has been selected. The referenced enumeration also establishes the unit of the enumeration value.X
Formal representations
XML Specification
 <xs:element name="IfcPropertyEnumeratedValue" type="ifc:IfcPropertyEnumeratedValue" substitutionGroup="ifc:IfcSimpleProperty" nillable="true"/>
 <xs:complexType name="IfcPropertyEnumeratedValue">
  <xs:complexContent>
   <xs:extension base="ifc:IfcSimpleProperty">
    <xs:sequence>
     <xs:element name="EnumerationValues" nillable="true" minOccurs="0">
      <xs:complexType>
       <xs:group ref="ifc:IfcValue" maxOccurs="unbounded"/>
       <xs:attribute ref="ifc:itemType" fixed="ifc:IfcValue"/>
       <xs:attribute ref="ifc:cType" fixed="list"/>
       <xs:attribute ref="ifc:arraySize" use="optional"/>
      </xs:complexType>
     </xs:element>
     <xs:element name="EnumerationReference" type="ifc:IfcPropertyEnumeration" nillable="true" minOccurs="0"/>
    </xs:sequence>
   </xs:extension>
  </xs:complexContent>
 </xs:complexType>
EXPRESS Specification
ENTITY IfcPropertyEnumeratedValue
 SUBTYPE OF (IfcSimpleProperty);
  EnumerationValues : OPTIONAL LIST [1:?] OF IfcValue;
  EnumerationReference : OPTIONAL IfcPropertyEnumeration;
 WHERE
  WR21 : NOT(EXISTS(EnumerationReference))
OR NOT(EXISTS(EnumerationValues))
OR (SIZEOF(QUERY(temp <* EnumerationValues |
temp IN EnumerationReference.EnumerationValues))
= SIZEOF(EnumerationValues));
END_ENTITY;

Link to EXPRESS-G diagram EXPRESS-G diagram

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