8.11.6.2 IfcCorrectUnitAssignment
8.11.6.2.1 Semantic definition
The function returns true, if the set of Units within an IfcUnitAssignment only include units with different UnitType's (for IfcNamedUnit and IfcDerivedUnit), and a maximum of one IfcMonetaryUnit.
Argument definitions: Units : (input) the set of IfcUnit's.
8.11.6.2.2 Formal representation
FUNCTION IfcCorrectUnitAssignment
  (Units : SET [1:?] OF IfcUnit)
   : LOGICAL;
  LOCAL
    NamedUnitNumber    : INTEGER := 0;
    DerivedUnitNumber  : INTEGER := 0;
    MonetaryUnitNumber : INTEGER := 0;
    NamedUnitNames     : SET OF IfcUnitEnum := [];
    DerivedUnitNames   : SET OF IfcDerivedUnitEnum := [];
  END_LOCAL;
  NamedUnitNumber    := SIZEOF(QUERY(temp <* Units | ('IFC4X3_ADD2.IFCNAMEDUNIT' IN TYPEOF(temp)) AND NOT(temp\IfcNamedUnit.UnitType = IfcUnitEnum.USERDEFINED)));
  DerivedUnitNumber  := SIZEOF(QUERY(temp <* Units | ('IFC4X3_ADD2.IFCDERIVEDUNIT' IN TYPEOF(temp)) AND NOT(temp\IfcDerivedUnit.UnitType = IfcDerivedUnitEnum.USERDEFINED)));
  MonetaryUnitNumber := SIZEOF(QUERY(temp <* Units |  'IFC4X3_ADD2.IFCMONETARYUNIT' IN TYPEOF(temp)));
  REPEAT i := 1 TO SIZEOF(Units);
    IF (('IFC4X3_ADD2.IFCNAMEDUNIT' IN TYPEOF(Units[i])) AND NOT(Units[i]\IfcNamedUnit.UnitType = IfcUnitEnum.USERDEFINED)) THEN
        NamedUnitNames := NamedUnitNames + Units[i]\IfcNamedUnit.UnitType;
    END_IF;
    IF (('IFC4X3_ADD2.IFCDERIVEDUNIT' IN TYPEOF(Units[i])) AND NOT(Units[i]\IfcDerivedUnit.UnitType = IfcDerivedUnitEnum.USERDEFINED)) THEN
        DerivedUnitNames := DerivedUnitNames + Units[i]\IfcDerivedUnit.UnitType;
    END_IF;
  END_REPEAT;
  RETURN((SIZEOF(NamedUnitNames) = NamedUnitNumber) AND (SIZEOF(DerivedUnitNames) = DerivedUnitNumber) AND (MonetaryUnitNumber <= 1));
END_FUNCTION;