Natural language names
frei definierbare Mengenliste
Quantity Set
Ensemble de quantités
Change log
IFC2x3 to IFC4
Semantic definitions at the entity
Entity definition

IfcQuantitySet is the the abstract supertype for all quantity sets attached to objects. The quantity set is a container class that holds the individual quantities within a quantity tree. These quantities are interpreted according to their name attribute and classified according to their measure type. Some quantity sets are included in the IFC specification and have a predefined set of quantities indicated by assigning a significant name. These quantity sets are listed as "quantity sets" within this specification. Quantity sets applicable to certain objects are listed in the object specification.

An IfcPropertySetTemplate may define the underlying structure, i.e. the required name, the applicable object or object types to which the quantity set can be attached, and the individual quantities that maybe included. Quantity sets are related to other objects by using the relationship object that refers to the corresponding object:

HISTORY  New entity in IFC4.
Inherited definitions from supertypes
Entity inheritance IfcElementQuantity IfcPropertySetDefinition IfcPropertyDefinition IfcRoot
Attribute inheritance
1GlobalIdIfcGloballyUniqueId Assignment of a globally unique identifier within the entire software world. X
2OwnerHistoryIfcOwnerHistory? Assignment of the information about the current ownership of that object, including owning actor, application, local identification and information captured about the recent changes of the object,
NOTE  only the last modification in stored - either as addition, deletion or modification.
IFC4 CHANGE  The attribute has been changed to be OPTIONAL.
3NameIfcLabel? Optional name for use by the participating software systems or users. For some subtypes of IfcRoot the insertion of the Name attribute may be required. This would be enforced by a where rule. X
4DescriptionIfcText? Optional description, provided for exchanging informative comments.X
S[0:?]Reference to the relationship IfcRelAssociates and thus to those externally defined concepts, like classifications, documents, or library information, which are associated to the property definition.X
S[0:?]The type object to which the property set is assigned. The property set acts as a shared property set to all occurrences of the type object.
NOTE  The relationship between the IfcPropertySetDefinition and the IfcTypeObject is a direct relationship, not utilizing IfcRelDefinesByProperties, for maintaining compatibility with earlier releases of this standard.
IFC4 CHANGE  The cardinality has been changed from 0:1 to 0:? with upward compatibility for file based exchange.
S[0:?]Relation to the property set template, via the objectified relationship IfcRelDefinesByTemplate, that, if given, provides the definition template for the property set or quantity set and its properties.
IFC4 CHANGE  New inverse relationship, change made with upward compatibility for file based exchange.
S[0:?]Reference to the relation to one or many object occurrences that are characterized by the property set definition. A single property set can be assigned to multiple object occurrences using the objectified relationship IfcRefDefinesByProperties.
IFC4 CHANGE Inverse attribute renamed from PropertyDefinitionOf with upward compatibility for file-based exchange.
Definitions applying to General Usage

Concept inheritance

#ConceptTemplateModel View
IdentitySoftware IdentityGeneral Usage
Revision ControlRevision ControlGeneral Usage
Formal representations
XML Specification
 <xs:element name="IfcQuantitySet" type="ifc:IfcQuantitySet" abstract="true" substitutionGroup="ifc:IfcPropertySetDefinition" nillable="true"/>
 <xs:complexType name="IfcQuantitySet" abstract="true">
   <xs:extension base="ifc:IfcPropertySetDefinition"/>
EXPRESS Specification
ENTITY IfcQuantitySet
 SUBTYPE OF (IfcPropertySetDefinition);

Link to EXPRESS-G diagram EXPRESS-G diagram

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