Natural language names
Semantic definitions at the type
Type definition

A label is the term by which something may be referred to. It is a string which represents the human-interpretable name of something and shall have a natural-language meaning.

Type: STRING of up to 255 characters

NOTE  Type adapted from label defined in ISO 10303-41.
HISTORY  New type in IFC2x.
IFC4 CHANGE  Previously recommended size restriction of 255 characters is now mandatory.

Value restrictions

As a human-readable string for naming purposes, a label is usually human-specified and locale-dependent (in contrast to purely machine-readable identifiers, IfcIdentifier).

NOTE  The set of characters that may appear in STRINGs exchanged in the exchange structure as defined in ISO 10303.21 is provided in ISO 10646. The encoding of characters in case of file-based exchange is defined in ISO 10303-21 and ISO 10303-28. Among else, these specifications define the encoding of 8-bit characters from ISO 8859-1...-16 and of 2-byte and 4-byte Unicode characters from ISO 10646.
NOTE  While IfcIdentifier is restricted to 255 characters, the size in exchange files after encoding may be considerably larger than 255 octets, depending on the particular encoding and on the contents of the identifier.
Formal representations
XML Specification
 <xs:simpleType name="IfcLabel">
  <xs:restriction base="xs:normalizedString">
   <xs:maxLength value="255"/>
EXPRESS Specification
TYPE IfcLabel = STRING (255);

Link to EXPRESS-G diagram EXPRESS-G diagram

References  References: IfcComplexPropertyTemplate IfcContext IfcObject IfcProxy IfcRoot IfcSimplePropertyTemplate IfcTypeProcess IfcTypeProduct IfcTypeResource IfcPerformanceHistory IfcRelAssociatesConstraint IfcEvent IfcEventType IfcRelSequence IfcTask IfcTaskType IfcWorkControl IfcElementQuantity IfcElementType IfcRelConnectsWithRealizingElements IfcSite IfcSpaceType IfcSpatialElement IfcSpatialElementType IfcSpatialZoneType IfcZone IfcBuildingSystem IfcDoor IfcDoorType IfcWindow IfcWindowType IfcDistributionSystem IfcActionRequest IfcCostSchedule IfcPermit IfcProjectOrder IfcStructuralLoadGroup IfcReinforcementDefinitionProperties IfcReinforcingBarType IfcReinforcingElement IfcReinforcingMeshType IfcActorRole IfcAddress IfcOrganization IfcPerson IfcPostalAddress IfcTelecomAddress IfcApproval IfcConstraint IfcMetric IfcObjective IfcReference IfcAppliedValue IfcResourceTime IfcSchedulingTime IfcTimeSeries IfcClassification IfcDocumentInformation IfcDocumentInformationRelationship IfcExternalReference IfcLibraryInformation IfcResourceLevelRelationship IfcAlignment2DSegment IfcAlignmentCurve IfcGridAxis IfcCartesianPointList2D IfcCartesianPointList3D IfcOffsetCurveByDistances IfcMaterial IfcMaterialConstituent IfcMaterialConstituentSet IfcMaterialLayer IfcMaterialLayerSet IfcMaterialProfile IfcMaterialProfileSet IfcMaterialRelationship IfcContextDependentUnit IfcConversionBasedUnit IfcDerivedUnit IfcMonetaryUnit IfcSimpleValue IfcColourSpecification IfcCurveStyleFont IfcCurveStyleFontAndScaling IfcPreDefinedItem IfcPresentationStyle IfcStyledItem IfcTextureCoordinateGenerator IfcLightSource IfcPresentationLayerAssignment IfcCompositeProfileDef IfcDerivedProfileDef IfcProfileDef IfcReinforcementBarProperties IfcPropertyEnumeration IfcPhysicalComplexQuantity IfcPhysicalQuantity IfcQuantityArea IfcQuantityCount IfcQuantityLength IfcQuantityTime IfcQuantityVolume IfcQuantityWeight IfcCoordinateReferenceSystem IfcGeometricRepresentationSubContext IfcProductRepresentation IfcRepresentation IfcRepresentationContext IfcShapeAspect IfcBoundaryCondition IfcStructuralConnectionCondition IfcStructuralLoad IfcApplication IfcTable IfcTableColumn

Link to this page  Link to this page