8.11.3.10 IfcSIUnit

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8.11.3.10.1 Semantic definition

The IfcSIUnit covers both standard base SI units such as meter and second, and derived SI units such as Pascal, square meter and cubic meter.

8.11.3.10.2 Entity inheritance

- IfcNamedUnit

8.11.3.10.3 Attributes

#	Attribute	Type	Description
IfcNamedUnit (2)
1	Dimensions	IfcDimensionalExponents	The dimensional exponents of the SI base units by which the named unit is defined.
2	UnitType	IfcUnitEnum	The type of the unit.
Click to show 2 hidden inherited attributes
IfcSIUnit (3)
3	Prefix	OPTIONAL IfcSIPrefix	The SI Prefix for defining decimal multiples and submultiples of the unit.
4	Name	IfcSIUnitName	The word, or group of words, by which the SI unit is referred to. NOTE Even though the SI system's base unit for mass is kilogram, the IfcSIUnit for mass is gram if no Prefix is asserted.
1*	Dimensions	IfcDimensionalExponents	This attribute is formally derived. `IfcDimensionsForSIUnit (SELF.Name)` The dimensional exponents of SI units are derived by function IfcDimensionsForSIUnit.

Table 8.11.3.10.A

8.11.3.10.4 Formal representation

 ENTITY IfcSIUnit
 SUBTYPE OF (IfcNamedUnit);
	Prefix : OPTIONAL IfcSIPrefix;
	Name : IfcSIUnitName;
 DERIVE
	 SELF\IfcNamedUnit.Dimensions : IfcDimensionalExponents := IfcDimensionsForSIUnit (SELF.Name);
END_ENTITY;

8.11.3.10.5 References

IfcNamedUnit

	ENTITY IfcSIUnit
	SUBTYPE OF (IfcNamedUnit);
	Prefix : OPTIONAL IfcSIPrefix;
	Name : IfcSIUnitName;
	DERIVE
	SELF\IfcNamedUnit.Dimensions : IfcDimensionalExponents := IfcDimensionsForSIUnit (SELF.Name);
	END_ENTITY;