IfcPropertyListValue

Semantic definitions at the entity

Entity definition

An IfcPropertyListValue defines a property that has several (numeric or descriptive) values assigned, these values are given by an ordered list. It defines a property - list value combination for which the property Name, an optional Description, the optional ListValues with measure type and optionally an Unit is given. An IfcPropertyListValue is a list of values. The order in which values appear is significant. All list members shall be of the same type.

The unit is handled by the Unit attribute, see Table 692 for an example of a list property:

If the Unit attribute is not given, then 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, then the unit assigned by the Unit attribute overrides the globally assigned unit.

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

Name ListValues Type
(through IfcValue) Unit

ApplicableSizes 1200 IfcPositiveLengthMeasure -

- 1600 IfcPositiveLengthMeasure -

- 2400 IfcPositiveLengthMeasure -

Table 692 — List property with values, measure types and units

HISTORY New entity in IFC2x2.

IFC4 CHANGE Attribute ListValues has been made OPTIONAL with upward compatibility for file based exchange.

Attribute definitions

#	Attribute	Type	Cardinality	Description	C
3	ListValues	IfcValue	L[1:?]	List of property values.	X
4	Unit	IfcUnit	[0:1]	Unit for the list values, if not given, the default value for the measure type (given by the TYPE of nominal value) is used as defined by the global unit assignment at IfcProject.	X

Formal Propositions

Rule	Description
WR31	All values within the list of values shall be of the same measure type.

Inherited definitions from supertypes

Entity inheritance

Attribute inheritance

#	Attribute	Type	Cardinality	Description	C
IfcPropertyAbstraction
	HasExternalReferences	IfcExternalReferenceRelationship @RelatedResourceObjects	S[0:?]	Reference to an external reference, e.g. library, classification, or document information, that is associated to the property definition.	X
IfcProperty
1	Name	IfcIdentifier	[1:1]	Name for this property. This label is the significant name string that defines the semantic meaning for the property.	X
2	Description	IfcText	[0:1]	Informative text to explain the property.	X
	PartOfPset	IfcPropertySet @HasProperties	S[0:?]	Reference to the IfcPropertySet by which the IfcProperty is referenced.	X
	PropertyForDependance	IfcPropertyDependencyRelationship @DependingProperty	S[0:?]	The property on whose value that of another property depends.	X
	PropertyDependsOn	IfcPropertyDependencyRelationship @DependantProperty	S[0:?]	The relating property on which the value of the property depends.	X
	PartOfComplex	IfcComplexProperty @HasProperties	S[0:?]	Reference to the IfcComplexProperty in which the IfcProperty is contained.	X
	HasConstraints	IfcResourceConstraintRelationship @RelatedResourceObjects	S[0:?]	User-defined constraints for the property.	X
	HasApprovals	IfcResourceApprovalRelationship @RelatedResourceObjects	S[0:?]	User-defined approvals for the property.	X
IfcSimpleProperty
IfcPropertyListValue
3	ListValues	IfcValue	L[1:?]	List of property values.	X
4	Unit	IfcUnit	[0:1]	Unit for the list values, if not given, the default value for the measure type (given by the TYPE of nominal value) is used as defined by the global unit assignment at IfcProject.	X

Formal representations

XSD Specification

 <xs:element name="IfcPropertyListValue" type="ifc:IfcPropertyListValue" substitutionGroup="ifc:IfcSimpleProperty" nillable="true"/>

 <xs:complexType name="IfcPropertyListValue">

  <xs:complexContent>

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

    <xs:sequence>

     <xs:element name="ListValues" 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="Unit" nillable="true" minOccurs="0">

      <xs:complexType>

       <xs:group ref="ifc:IfcUnit"/>

      </xs:complexType>

     </xs:element>

    </xs:sequence>

   </xs:extension>

  </xs:complexContent>

 </xs:complexType>

EXPRESS Specification


ENTITY IfcPropertyListValue

 SUBTYPE OF (IfcSimpleProperty);

  ListValues : OPTIONAL LIST [1:?] OF IfcValue;

  Unit : OPTIONAL IfcUnit;

 WHERE

  WR31 : SIZEOF(QUERY(temp <* SELF.ListValues | 
  NOT(TYPEOF(SELF.ListValues[1]) = TYPEOF(temp))
  )) = 0;
END_ENTITY;

 EXPRESS-G diagram

Item	Change	Description
IFC2x3 to IFC4
IfcPropertyListValue
ListValues	MODIFIED	Instantiation changed to OPTIONAL.
IFC4 Addendum 1
IfcPropertyListValue
HasConstraints	ADDED
HasApprovals	ADDED

	Merkmal mit Listenwert
	Property List Value
	Propriété à liste de valeurs