gml:ConcatenatedOperation is an ordered sequence of two or more coordinate operations. This sequence of operations is constrained by the requirement that the source coordinate reference system of step (n+1) must be the same as the target coordinate reference system of step (n). The source coordinate reference system of the first step and the target coordinate reference system of the last step are the source and target coordinate reference system associated with the concatenated operation. Instead of a forward operation, an inverse operation may be used for one or more of the operation steps mentioned above, if the inverse operation is uniquely defined by the forward operation.The gml:coordOperation property elements are an ordered sequence of associations to the two or more operations used by this concatenated operation. The AggregationAttributeGroup should be used to specify that the coordOperation associations are ordered.
The attribute gml:id supports provision of a handle for the XML element representing a GML Object. Its use is mandatory for all GML objects. It is of XML type ID, so is constrained to be unique in the XML document within which it occurs.
Source
<complexType name="ConcatenatedOperationType"><annotation><documentation>gml:ConcatenatedOperation is an ordered sequence of two or more coordinate operations. This sequence of operations is constrained by the requirement that the source coordinate reference system of step (n+1) must be the same as the target coordinate reference system of step (n). The source coordinate reference system of the first step and the target coordinate reference system of the last step are the source and target coordinate reference system associated with the concatenated operation. Instead of a forward operation, an inverse operation may be used for one or more of the operation steps mentioned above, if the inverse operation is uniquely defined by the forward operation. The gml:coordOperation property elements are an ordered sequence of associations to the two or more operations used by this concatenated operation. The AggregationAttributeGroup should be used to specify that the coordOperation associations are ordered.</documentation></annotation><complexContent><extension base="gml:AbstractCoordinateOperationType"><sequence><element ref="gml:coordOperation" minOccurs="2" maxOccurs="unbounded"/></sequence><attributeGroup ref="gml:AggregationAttributeGroup"/></extension></complexContent></complexType>