gml:Observation

The content model is a straightforward extension of gml:AbstractFeatureType; it automatically has the gml:identifier, gml:description, gml:descriptionReference, gml:name, and gml:boundedBy properties. 
The gml:validTime element describes the time of the observation. Note that this may be a time instant or a time period.
The gml:using property contains or references a description of a sensor, instrument or procedure used for the observation.
The gml:target property contains or references the specimen, region or station which is the object of the observation. This property is particularly useful for remote observations, such as photographs, where a generic location property might apply to the location of the camera or the location of the field of view, and thus may be ambiguous.  
The gml:subject element is provided as a convenient synonym for gml:target. This is the term commonly used in phtotography.  
The gml:resultOf property indicates the result of the observation.  The value may be inline, or a reference to a value elsewhere.

Element information

Content

• Sequence [1..1]
  from type gml:AbstractGMLType
  from group gml:StandardObjectProperties
  gml:metaDataProperty [0..*]    deprecated
  gml:description [0..1]    The value of this property is a text description of the object. gml:description uses gml:StringOrRefType as its content model, so it may contain a simple text string content, or carry a reference to an external description. The use of gml:description to reference an external description has been deprecated and replaced by the gml:descriptionReference property.
  gml:descriptionReference [0..1]    The value of this property is a remote text description of the object. The xlink:href attribute of the gml:descriptionReference property references the external description.
  gml:identifier [0..1]    Often, a special identifier is assigned to an object by the maintaining authority with the intention that it is used in references to the object For such cases, the codeSpace shall be provided. That identifier is usually unique either globally or within an application domain. gml:identifier is a pre-defined property for such identifiers.
  gml:name [0..*]    The gml:name property provides a label or identifier for the object, commonly a descriptive name. An object may have several names, typically assigned by different authorities. gml:name uses the gml:CodeType content model. The authority for a name is indicated by the value of its (optional) codeSpace attribute. The name may or may not be unique, as determined by the rules of the organization responsible for the codeSpace. In common usage there will be one name per authority, so a processing application may select the name from its preferred codeSpace.
  from type gml:AbstractFeatureType
  gml:boundedBy [0..1]    This property describes the minimum bounding box or rectangle that encloses the entire feature.
  Choice [0..1]
  from subst. group gml:location
  gml:location    deprecated
  gml:priorityLocation    deprecated
  1. gml:validTime [1..1]    gml:validTime is a convenience property element.
  2. gml:using [0..1]    
  3. Choice [0..1]
     from subst. group gml:target
     gml:target    
     gml:subject    
  4. gml:resultOf [1..1]    

Attributes

Used in

• Type gml:ArrayAssociationType (Element gml:members)
• Type gml:FeatureArrayPropertyType (Element gml:featureMembers)
• Type gml:ProcedurePropertyType (Element gml:using)
• Type gml:FeaturePropertyType (Elements gml:featureMember, gml:featureProperty)
• Type gml:TargetPropertyType (Elements gml:target, gml:subject)

Substitution hierarchy

• gml:AbstractObject
  • can be substituted with gml:AbstractGML
    • can be substituted with gml:AbstractFeature
      • can be substituted with gml:Observation
        • can be substituted with gml:DirectedObservation
          • can be substituted with gml:DirectedObservationAtDistance

Sample instance

<gml:Observation gml:id="ID">
   <gml:metaDataProperty>
      <gml:GenericMetaData>Any text, intermingled with:
         <!--any element-->
      </gml:GenericMetaData>
   </gml:metaDataProperty>
   <gml:description>string</gml:description>
   <gml:descriptionReference/>
   <gml:identifier codeSpace="http://www.example.com/">string</gml:identifier>
   <gml:name>string</gml:name>
   <gml:boundedBy>
      <gml:Envelope>
         <gml:lowerCorner>1.0 1.0</gml:lowerCorner>
         <gml:upperCorner>1.0 1.0</gml:upperCorner>
      </gml:Envelope>
   </gml:boundedBy>
   <gml:location>
      <gml:MultiGeometry gml:id="ID">
         <gml:metaDataProperty>...
         </gml:metaDataProperty>
         <gml:description>string</gml:description>
         <gml:descriptionReference/>
         <gml:identifier codeSpace="http://www.example.com/">string</gml:identifier>
         <gml:name>string</gml:name>
         <gml:geometryMember>...
         </gml:geometryMember>
         <gml:geometryMembers>...
         </gml:geometryMembers>
      </gml:MultiGeometry>
   </gml:location>
   <gml:validTime>
      <gml:TimeInstant gml:id="ID">
         <gml:metaDataProperty>...
         </gml:metaDataProperty>
         <gml:description>string</gml:description>
         <gml:descriptionReference/>
         <gml:identifier codeSpace="http://www.example.com/">string</gml:identifier>
         <gml:name>string</gml:name>
         <gml:relatedTime>...
         </gml:relatedTime>
         <gml:timePosition>12:00:00</gml:timePosition>
      </gml:TimeInstant>
   </gml:validTime>
   <gml:using>
      <gml:MultiPointCoverage gml:id="ID">
         <gml:metaDataProperty>...
         </gml:metaDataProperty>
         <gml:description>string</gml:description>
         <gml:descriptionReference/>
         <gml:identifier codeSpace="http://www.example.com/">string</gml:identifier>
         <gml:name>string</gml:name>
         <gml:boundedBy>...
         </gml:boundedBy>
         <gml:location>...
         </gml:location>
         <gml:domainSet>...
         </gml:domainSet>
         <gml:rangeSet>...
         </gml:rangeSet>
         <gml:coverageFunction>...
         </gml:coverageFunction>
      </gml:MultiPointCoverage>
   </gml:using>
   <gml:target>
      <gml:MultiPointCoverage gml:id="ID">
         <gml:metaDataProperty>...
         </gml:metaDataProperty>
         <gml:description>string</gml:description>
         <gml:descriptionReference/>
         <gml:identifier codeSpace="http://www.example.com/">string</gml:identifier>
         <gml:name>string</gml:name>
         <gml:boundedBy>...
         </gml:boundedBy>
         <gml:location>...
         </gml:location>
         <gml:domainSet>...
         </gml:domainSet>
         <gml:rangeSet>...
         </gml:rangeSet>
         <gml:coverageFunction>...
         </gml:coverageFunction>
      </gml:MultiPointCoverage>
   </gml:target>
   <gml:resultOf>
      <!--any element-->
   </gml:resultOf>
</gml:Observation>