8.11.3.11 IfcUnitAssignment

Assignation d'unité
Einheit - Zuweisung

IfcUnitAssignment indicates a set of units which may be assigned. Within an IfcUnitAssigment each unit definition shall be unique; that is, there shall be no redundant unit definitions for the same unit type such as length unit or area unit. For currencies, there shall be only a single IfcMonetaryUnit within an IfcUnitAssignment.

NOTE  A IfcProject has a unit assignment which establishes a set of units which will be used globally within the project, if not otherwise defined. Other objects may have local unit assignments if there is a requirement for them to make use of units which do not fall within the project unit assignment.
HISTORY  New entity in IFC1.5.1.

XSD Specification:

 <xs:element name="IfcUnitAssignment" type="ifc:IfcUnitAssignment" substitutionGroup="ifc:Entity" nillable="true"/>
 <xs:complexType name="IfcUnitAssignment">
  <xs:complexContent>
   <xs:extension base="ifc:Entity">
    <xs:sequence>
     <xs:element name="Units">
      <xs:complexType>
       <xs:group ref="ifc:IfcUnit" maxOccurs="unbounded"/>
       <xs:attribute ref="ifc:itemType" fixed="ifc:IfcUnit"/>
       <xs:attribute ref="ifc:cType" fixed="set"/>
       <xs:attribute ref="ifc:arraySize" use="optional"/>
      </xs:complexType>
     </xs:element>
    </xs:sequence>
   </xs:extension>
  </xs:complexContent>
 </xs:complexType>

EXPRESS Specification:

ENTITY IfcUnitAssignment;
Units : SET [1:?] OF IfcUnit;
WHERE
WR01 : IfcCorrectUnitAssignment(Units);
END_ENTITY;

Link to EXPRESS-G diagram EXPRESS-G diagram

Attribute Definitions:

Units : Units to be included within a unit assignment.

Formal Propositions:

WR01 : Checks that the set of globally assigned units has each unit type (either of type IfcNamedUnit,IfcDerivedUnit, or IfcMonetaryUnit) defined only once.

Inheritance Graph:

ENTITY IfcUnitAssignment
ENTITY IfcUnitAssignment
Units : SET [1:?] OF IfcUnit;
END_ENTITY;

Examples:

Link to this page  Link to this page