minimumOccurs Operation parameters and groups .1 GeneralOperationParameter

Copyright © 2007 Open Geospatial Consortium, Inc. All Rights Reserved. 137 complexContent extension base=gml:AbstractGeneralOperationParameterType sequence element ref=gml:maximumOccurs minOccurs=0 element ref=gml:parameter minOccurs=2 maxOccurs=unbounded sequence extension complexContent complexType gml:OperationParameterGroup is the definition of a group of parameters used by an operation method. This complex type is expected to be used or extended for all applicable operation methods, without defining operation- method-specialized element names. The gml:parameter elements are an unordered list of associations to the set of operation parameters that are members of this group.

12.6.6.7 maximumOccurs

element name=maximumOccurs type=positiveInteger gml:maximumOccurs is the maximum number of times that values for this parameter group may be included. If this attribute is omitted, the maximum number shall be one.

12.6.6.8 OperationParameterPropertyType

complexType name=OperationParameterGroupPropertyType sequence minOccurs=0 element ref=gml:OperationParameterGroup sequence attributeGroup ref=gml:AssociationAttributeGroup complexType gml:OperationParameterPropertyType is a property type for association roles to an operation parameter group, either referencing or containing the definition of that parameter group. 13 GML schema — Topology

13.1 General concepts

13.1.1 Overview

Topology is the branch of mathematics describing the properties of objects which are invariant under continuous deformation. For example, a circle is topologically equivalent to an ellipse because one can be transformed into the other by stretching. In geographic modelling, the foremost use of topology is in accelerating computational geometry. The constructs of topology allow characterization of the spatial relationships between objects using simple combinatorial or algebraic algorithms. Topology, realized by the appropriate geometry, also allows a compact and unambiguous mechanism for expressing shared geometry among geographic features. NOTE 1 The topology model of GML complies with ISO 19107. The underlying concepts of the types and elements of the GML topology model are discussed in this document in more detail. This clause describes the topology schema components as specified by GML.