The required n attribute is the number of point set references in the list.
Source
<xs:element name="PointList" type="PointListType" minOccurs="0"><xs:annotation><xs:documentation>The optional PointList element is a list of references to nominal target measurement points for the feature.</xs:documentation></xs:annotation></xs:element>
<xs:element name="SubstituteFeatureAlgorithm" type="SubstituteFeatureAlgorithmType" minOccurs="0"><xs:annotation><xs:documentation>The optional SubstituteFeatureAlgorithm element is the substitute feature data fitting algorithm for the shape feature.</xs:documentation></xs:annotation></xs:element>
The ShapeFeatureNominalBaseType is the abstract base type for shape feature nominals. A shape feature nominal holds that portion of shape feature nominal information which cannot be shared among several features, e.g. feature location.
The id attribute is the QIF id of the feature, used for referencing.
Source
<xs:complexType name="ShapeFeatureNominalBaseType" abstract="true"><xs:annotation><xs:documentation>The ShapeFeatureNominalBaseType is the abstract base type for shape feature nominals. A shape feature nominal holds that portion of shape feature nominal information which cannot be shared among several features, e.g. feature location.</xs:documentation></xs:annotation><xs:complexContent><xs:extension base="FeatureNominalBaseType"><xs:sequence><xs:element name="PointList" type="PointListType" minOccurs="0"><xs:annotation><xs:documentation>The optional PointList element is a list of references to nominal target measurement points for the feature.</xs:documentation></xs:annotation></xs:element><xs:element name="SubstituteFeatureAlgorithm" type="SubstituteFeatureAlgorithmType" minOccurs="0"><xs:annotation><xs:documentation>The optional SubstituteFeatureAlgorithm element is the substitute feature data fitting algorithm for the shape feature.</xs:documentation></xs:annotation></xs:element></xs:sequence></xs:extension></xs:complexContent></xs:complexType>