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sequence extension
complexContent complexType
element name=LinearReferencingMethod type=gmllr:LinearReferencingMethodType substitutionGroup=gml:AbstractGML
gmllr:LinearReferencingMethod implements ISO 19148 LR_LinearReferencingMethod see ISODIS 19148, 6.2.10.
A gmllr:LinearReferencingMethod specifies the manner in which measurements are made along a linear element.
The element gmllr:name specifies the name of the Linear Referencing Method, such as kilometre-point. Allowable values are specified by the gmllr:LRMNameType codelist.
The element gmllr:type specifies the type of Linear Referencing Method. Allowable values are specified by the gmllr:LRMTypeType codelist.
The element gmllr:units specifies the units of measure used by the Linear Referencing Method as a gml:UomIdentifier. This applies to measurements made along the linear element.
The optional element gmllr:constraint allows for optional string values which specify any constraints imposed by the Linear Referencing Method.
9.3.9 LinearReferencingMethodPropertyType
complexType name=LinearReferencingMethodPropertyType sequence minOccurs=0
element ref=gmllr:LinearReferencingMethod sequence
attributeGroup ref=gml:AssociationAttributeGroup complexType
A property that has a Linear Referencing Method as its value domain may either be an appropriate Linear Referencing Method encapsulated in an element of this type or an XLink reference to a remote Linear
Referencing Method where remote includes Linear Referencing Methods located elsewhere in the same document. Either the reference or the contained element shall be given, but neither both nor none.
9.3.10 DistanceExpressionType
complexType name=DistanceExpressionType complexContent
extension base=gml:AbstractGMLType sequence
element name=distanceAlong type=gmllr:MeasureType element name=referent type=gmllr:AlongReferentPropertyType
minOccurs=0 sequence
extension complexContent
complexType element name=DistanceExpression type=gmllr:DistanceExpressionType
substitutionGroup=gml:AbstractGML
34 Copyright © 2012 Open Geospatial Consortium
gmllr:DistanceExpression implements ISO 19148 LR_DistanceExpression see ISODIS 19148, 6.2.12.
A gmllr:DistanceExpression specifies the linear referenced measure value. This includes the distance measured along the linear element. If the Linear Referencing Method gmllr:LRMType is relative, the
distance expression also includes an along referent to specify where the measuring begins. Otherwise, measuring begins at the start of the linear element. Measuring is in the direction of the linear element, unless
a towards referent is provided.
The element gmllr:distanceAlong specifies the measure value usually a distance of the distance expression. It is of type gmllr:MeasureType. gmllr:MeasureType is the same as gml:MeasureType
except that the uom value is optional. If none is provided, the uom value defaults to the units value of the Linear Referencing Method.
If the Linear Referencing Method gmllr:type is ‘absolute’, the distance along is measured from the start of the linear element. If ‘relative’, it is measured from the along referent’s from referent. If ‘interpolative’, it is
based upon the default length or weight of the linear element gmllr:measure.
The optional element gmllr:referent specifies the referent associated with the distance expression gmllr:distanceAlong value. A referent is only appropriate if the Linear Referencing Method
gmllr:type is relative. If the referent is absent, then the position is measured from the start of the linear element.
9.3.11 DistanceExpressionPropertyType
