ifc:IfcGridTypeEnum

<xs:simpleType name="IfcGridTypeEnum">
  <xs:restriction base="xs:string">
    <xs:enumeration value="rectangular"/>
    <xs:enumeration value="radial"/>
    <xs:enumeration value="triangular"/>
    <xs:enumeration value="irregular"/>
    <xs:enumeration value="userdefined"/>
    <xs:enumeration value="notdefined"/>
  </xs:restriction>
</xs:simpleType>