Typed ValueExtents: CategoryExtent, CountExtent, QuantityExtent

Copyright © 2007 Open Geospatial Consortium, Inc. All Rights Reserved. 191 restriction simpleType element name=QuantityExtent type=gml:QuantityExtentType substitutionGroup=gml:AbstractValue complexType name=QuantityExtentType simpleContent restriction base=gml:MeasureOrNilReasonListType length value=2 restriction simpleContent complexType A gml:QuantityExtent element or another element using this type will contain two values and a scale. EXAMPLE 1 gml:QuantityExtent uom=‖mm‖0. 9.5gml:QuantityExtent An element of gml:CategoryExtentType is useful if the codeSpace defines a set of ordered terms. EXAMPLE 2 my:AgeRange codeSpace=‖http:iugg.orggeologicalPeriods‖Cambrian Devonianmy:AgeRange Any value extent may describe a single-ended interval by using a NilReason value for one of the limits. EXAMPLE 3 gml:CountExtent53 inapplicablegml:CountExtent describes the integers starting with 53.

16.4.13 BooleanPropertyType, CategoryPropertyType, CountPropertyType, QuantityPropertyType

A set of convenience types gml:BooleanPropertyType, gml:CategoryPropertyType, gml:CountPropertyType, gml:QuantityPropertyType are provided for properties whose content is a specific member of the gml:AbstractScalarValue substitution group. Their definitions follow the same pattern, as exemplified by the definition of gml:BooleanPropertyType: complexType name=BooleanPropertyType sequence minOccurs=0 element ref=gml:Boolean sequence attributeGroup ref=gml:AssociationAttributeGroup complexType 17 GML schema — Directions

17.1 Direction schema

The direction schema components provide the GML application schema developer with a standard property element to describe direction, and associated objects that may be used to express orientation, direction, heading, bearing or other directional aspects of geographic features. NOTE The corresponding schema document is identified by the following location-independent name using URN syntax: urn:x-ogc:specification:gml:schema-xsd:direction:3.2.1

17.2 direction, DirectionPropertyType

The property gml:direction is intended as a predefined property expressing a direction to be assigned to features defined in a GML application schema. It is declared as follows: 192 Copyright © 2007 Open Geospatial Consortium, Inc. All Rights Reserved. element name=direction type=gml:DirectionPropertyType complexType name=DirectionPropertyType sequence minOccurs=0 choice element name=DirectionVector type=gml:DirectionVectorType element name=DirectionDescription type=gml:DirectionDescriptionType element name=CompassPoint type=gml:CompassPointEnumeration element name=DirectionKeyword type=gml:CodeType element name=DirectionString type=gml:StringOrRefType choice sequence attributeGroup ref=gml:OwnershipAttributeGroup attributeGroup ref=gml:AssociationAttributeGroup complexType The two alternative kinds of direction specifications, a vector or a description, are specified in the following subclauses.

17.3 DirectionVectorType

Direction vectors are specified by providing components of a vector as follows: complexType name=DirectionVectorType choice element ref=gml:vector sequence element name=horizontalAngle type=gml:AngleType element name=verticalAngle type=gml:AngleType sequence choice complexType The gml:vector element is described in 10.1.4.5. EXAMPLE This form may appear in a data instance as follows: gml:direction gml:DirectionVector gml:vector srsName=wgs840.0 45.0gml:vector gml:DirectionVector gml:direction The use of the alternative representation via angles has been deprecated, gml:vector shall be used instead.

17.4 DirectionDescriptionType

Direction descriptions are specified by a compass point code, a keyword, a textual description or a reference to a description. The gml:DirectionDescriptionType element is declared as follows: complexType name=DirectionDescriptionType choice element name=compassPoint type=gml:CompassPointEnumeration element name=keyword type=gml:CodeType element name=description type=string element name=reference type=gml:ReferenceType choice complexType