#### IfcUnit

Natural language names

##### Semantic definitions at the type

Type definition

Definition from ISO/CD 10303-41:1992: A unit is a physical quantity, with a value of one, which is used as a standard in terms of which other quantities are expressed.

> NOTE: Select item IfcMonetaryUnit is an addition to ISO/CD 10303-41:1992.

> NOTE Corresponding STEP name: unit, please refer to ISO/IS 10303-41:1994 for the final definition of the formal standard.

SELECT

- IfcNamedUnit A unit which is identified by a name.
- IfcDerivedUnit A unit which is derived from an expression of units.
- IfcMonetaryUnit A unit for defining currencies.

HISTORY New type in IFC Release 1.5.1.
Enumeration definition

Constant | Description
--- | ---
IfcDerivedUnit |
IfcNamedUnit |
IfcMonetaryUnit |

##### Formal representations

XSD Specification
`<xs:group name="IfcUnit">
<xs:choice>
<xs:element ref="ifc:IfcDerivedUnit"/>
<xs:element ref="ifc:IfcNamedUnit"/>
</xs:choice>
</xs:group>
`
EXPRESS Specification
`TYPE IfcUnit = SELECT (
IfcDerivedUnit,
IfcNamedUnit);
END_TYPE;

EXPRESS-G diagram

`

Link to this page