observation

Table of Contents

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Schema Document Properties

Target Namespacehttp://www.opengis.net/gml
Version3.2.0
Element and Attribute Namespaces
  • Global element and attribute declarations belong to this schema's target namespace.
  • By default, local element declarations belong to this schema's target namespace.
  • By default, local attribute declarations have no namespace.
Schema Composition
DocumentationSee ISO/DIS 19136 Clause 19. A GML observation models the act of observing, often with a camera, a person or some form of instrument. An observation feature describes the “metadata” associated with an information capture event, together with a value for the result of the observation. This covers a broad range of cases, from a tourist photo (not the photo but the act of taking the photo), to images acquired by space borne sensors or the measurement of a temperature 5 meters below the surfaces of a lake. The basic structures introduced in this schema are intended to serve as the foundation for more comprehensive schemas for scientific, technical and engineering measurement schemas.
Application Dataobservation.xsd
More information at: urn:ogc:specification:gml:schema-xsd:observation:3.2.0.

Declared Namespaces

PrefixNamespace
Default namespacehttp://www.w3.org/2001/XMLSchema
xmlhttp://www.w3.org/XML/1998/namespace
gmlhttp://www.opengis.net/gml
Schema Component Representation
<schema targetNamespace="http://www.opengis.net/gml" elementFormDefault="qualified" version="3.2.0">
<include schemaLocation="feature.xsd"/>
<include schemaLocation="direction.xsd"/>
<include schemaLocation="valueObjects.xsd"/>
...
</schema>
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Global Declarations

Element: DirectedObservation

NameDirectedObservation
Typegml:DirectedObservationType
Nillableno
Abstractno
DocumentationA gml:DirectedObservation is the same as an observation except that it adds an additional gml:direction property. This is the direction in which the observation was acquired. Clearly this applies only to certain types of observations such as visual observations by people, or observations obtained from terrestrial cameras.
XML Instance Representation
<gml:DirectedObservation
gml:id="[1]">
<gml:metaDataProperty> ... </gml:metaDataProperty> [0..*]
<gml:description> ... </gml:description> [0..1]
<gml:descriptionReference> ... </gml:descriptionReference> [0..1]
<gml:identifier> ... </gml:identifier> [0..1]
<gml:name> ... </gml:name> [0..*]
<gml:boundedBy> ... </gml:boundedBy> [0..1]
<gml:location> ... </gml:location> [0..1]
<gml:validTime> ... </gml:validTime> [1]
<gml:using> ... </gml:using> [0..1]
<gml:target> ... </gml:target> [0..1]
<gml:resultOf> ... </gml:resultOf> [1]
<gml:direction> ... </gml:direction> [1]
</gml:DirectedObservation>
Schema Component Representation
<element name="DirectedObservation" type="gml:DirectedObservationType" substitutionGroup="gml:Observation"/>
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Element: DirectedObservationAtDistance

NameDirectedObservationAtDistance
Typegml:DirectedObservationAtDistanceType
Nillableno
Abstractno
Documentationgml:DirectedObservationAtDistance adds an additional distance property. This is the distance from the observer to the subject of the observation. Clearly this applies only to certain types of observations such as visual observations by people, or observations obtained from terrestrial cameras.
XML Instance Representation
<gml:DirectedObservationAtDistance
gml:id="[1]">
<gml:metaDataProperty> ... </gml:metaDataProperty> [0..*]
<gml:description> ... </gml:description> [0..1]
<gml:descriptionReference> ... </gml:descriptionReference> [0..1]
<gml:identifier> ... </gml:identifier> [0..1]
<gml:name> ... </gml:name> [0..*]
<gml:boundedBy> ... </gml:boundedBy> [0..1]
<gml:location> ... </gml:location> [0..1]
<gml:validTime> ... </gml:validTime> [1]
<gml:using> ... </gml:using> [0..1]
<gml:target> ... </gml:target> [0..1]
<gml:resultOf> ... </gml:resultOf> [1]
<gml:direction> ... </gml:direction> [1]
<gml:distance> gml:MeasureType </gml:distance> [1]
</gml:DirectedObservationAtDistance>
Schema Component Representation
<element name="DirectedObservationAtDistance" type="gml:DirectedObservationAtDistanceType" substitutionGroup="gml:DirectedObservation"/>
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Element: Observation

NameObservation
Typegml:ObservationType
Nillableno
Abstractno
DocumentationThe 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. If the value is inline, it shall be a member of the gml:AbstractObject substitution group.
XML Instance Representation
<gml:Observation
gml:id="[1]">
<gml:metaDataProperty> ... </gml:metaDataProperty> [0..*]
<gml:description> ... </gml:description> [0..1]
<gml:descriptionReference> ... </gml:descriptionReference> [0..1]
<gml:identifier> ... </gml:identifier> [0..1]
<gml:name> ... </gml:name> [0..*]
<gml:boundedBy> ... </gml:boundedBy> [0..1]
<gml:location> ... </gml:location> [0..1]
<gml:validTime> ... </gml:validTime> [1]
<gml:using> ... </gml:using> [0..1]
<gml:target> ... </gml:target> [0..1]
<gml:resultOf> ... </gml:resultOf> [1]
</gml:Observation>
Schema Component Representation
<element name="Observation" type="gml:ObservationType" substitutionGroup="gml:AbstractFeature"/>
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Element: resultOf

NameresultOf
Typegml:ResultType
Nillableno
Abstractno
XML Instance Representation
<gml:resultOf
owns="boolean [0..1]"
xlink:type="simple [0..1]"
xlink:href="[0..1]"
xlink:role="[0..1]"
xlink:arcrole="[0..1]"
xlink:title="[0..1]"
xlink:show="[0..1]"
xlink:actuate="[0..1]"
nilReason="gml:NilReasonType [0..1]"
gml:remoteSchema="[0..1]">
Start Sequence [0..1]
<gml:AbstractObject> ... </gml:AbstractObject> [1]
End Sequence
</gml:resultOf>
Schema Component Representation
<element name="resultOf" type="gml:ResultType"/>
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Element: subject

  • This element can be used wherever the following element is referenced:
Namesubject
Typegml:TargetPropertyType
Nillableno
Abstractno
XML Instance Representation
<gml:subject
owns="boolean [0..1]"
xlink:type="simple [0..1]"
xlink:href="[0..1]"
xlink:role="[0..1]"
xlink:arcrole="[0..1]"
xlink:title="[0..1]"
xlink:show="[0..1]"
xlink:actuate="[0..1]"
nilReason="gml:NilReasonType [0..1]"
gml:remoteSchema="[0..1]">
Start Choice [0..1]
<gml:AbstractFeature> ... </gml:AbstractFeature> [1]
<gml:AbstractGeometry> ... </gml:AbstractGeometry> [1]
End Choice
</gml:subject>
Schema Component Representation
<element name="subject" type="gml:TargetPropertyType" substitutionGroup="gml:target"/>
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Element: target

  • The following elements can be used wherever this element is referenced:
Nametarget
Typegml:TargetPropertyType
Nillableno
Abstractno
XML Instance Representation
<gml:target
owns="boolean [0..1]"
xlink:type="simple [0..1]"
xlink:href="[0..1]"
xlink:role="[0..1]"
xlink:arcrole="[0..1]"
xlink:title="[0..1]"
xlink:show="[0..1]"
xlink:actuate="[0..1]"
nilReason="gml:NilReasonType [0..1]"
gml:remoteSchema="[0..1]">
Start Choice [0..1]
<gml:AbstractFeature> ... </gml:AbstractFeature> [1]
<gml:AbstractGeometry> ... </gml:AbstractGeometry> [1]
End Choice
</gml:target>
Schema Component Representation
<element name="target" type="gml:TargetPropertyType"/>
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Element: using

Nameusing
Typegml:ProcedurePropertyType
Nillableno
Abstractno
XML Instance Representation
<gml:using
owns="boolean [0..1]"
xlink:type="simple [0..1]"
xlink:href="[0..1]"
xlink:role="[0..1]"
xlink:arcrole="[0..1]"
xlink:title="[0..1]"
xlink:show="[0..1]"
xlink:actuate="[0..1]"
nilReason="gml:NilReasonType [0..1]"
gml:remoteSchema="[0..1]">
Start Sequence [0..1]
<gml:AbstractFeature> ... </gml:AbstractFeature> [1]
End Sequence
</gml:using>
Schema Component Representation
<element name="using" type="gml:ProcedurePropertyType"/>
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Global Definitions

Complex Type: DirectedObservationAtDistanceType

Super-types:gml:AbstractFeatureType < ObservationType (by extension) < DirectedObservationType (by extension) < DirectedObservationAtDistanceType (by extension)
Sub-types:None
NameDirectedObservationAtDistanceType
Abstractno
XML Instance Representation
<...
gml:id="[1]">
<gml:description> ... </gml:description> [0..1]
<gml:identifier> ... </gml:identifier> [0..1]
<gml:name> ... </gml:name> [0..*]
<gml:boundedBy> ... </gml:boundedBy> [0..1]
<gml:location> ... </gml:location> [0..1]
<gml:validTime> ... </gml:validTime> [1]
<gml:using> ... </gml:using> [0..1]
<gml:target> ... </gml:target> [0..1]
<gml:resultOf> ... </gml:resultOf> [1]
<gml:direction> ... </gml:direction> [1]
<gml:distance> gml:MeasureType </gml:distance> [1]
</...>
Schema Component Representation
<complexType name="DirectedObservationAtDistanceType">
<complexContent>
<extension base="gml:DirectedObservationType">
<sequence>
<element name="distance" type="gml:MeasureType"/>
</sequence>
</extension>
</complexContent>
</complexType>
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Complex Type: DirectedObservationType

Super-types:gml:AbstractFeatureType < ObservationType (by extension) < DirectedObservationType (by extension)
Sub-types:
NameDirectedObservationType
Abstractno
XML Instance Representation
<...
gml:id="[1]">
<gml:description> ... </gml:description> [0..1]
<gml:identifier> ... </gml:identifier> [0..1]
<gml:name> ... </gml:name> [0..*]
<gml:boundedBy> ... </gml:boundedBy> [0..1]
<gml:location> ... </gml:location> [0..1]
<gml:validTime> ... </gml:validTime> [1]
<gml:using> ... </gml:using> [0..1]
<gml:target> ... </gml:target> [0..1]
<gml:resultOf> ... </gml:resultOf> [1]
<gml:direction> ... </gml:direction> [1]
</...>
Schema Component Representation
<complexType name="DirectedObservationType">
<complexContent>
<extension base="gml:ObservationType">
<sequence>
<element ref="gml:direction"/>
</sequence>
</extension>
</complexContent>
</complexType>
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Complex Type: ObservationType

Super-types:gml:AbstractFeatureType < ObservationType (by extension)
Sub-types:
NameObservationType
Abstractno
XML Instance Representation
<...
gml:id="[1]">
<gml:description> ... </gml:description> [0..1]
<gml:identifier> ... </gml:identifier> [0..1]
<gml:name> ... </gml:name> [0..*]
<gml:boundedBy> ... </gml:boundedBy> [0..1]
<gml:location> ... </gml:location> [0..1]
<gml:validTime> ... </gml:validTime> [1]
<gml:using> ... </gml:using> [0..1]
<gml:target> ... </gml:target> [0..1]
<gml:resultOf> ... </gml:resultOf> [1]
</...>
Schema Component Representation
<complexType name="ObservationType">
<complexContent>
<extension base="gml:AbstractFeatureType">
<sequence>
<element ref="gml:validTime"/>
<element ref="gml:using" minOccurs="0"/>
<element ref="gml:target" minOccurs="0"/>
<element ref="gml:resultOf"/>
</sequence>
</extension>
</complexContent>
</complexType>
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Complex Type: ProcedurePropertyType

Super-types:None
Sub-types:None
NameProcedurePropertyType
Abstractno
XML Instance Representation
<...
owns="boolean [0..1]"
xlink:type="simple [0..1]"
xlink:href="[0..1]"
xlink:role="[0..1]"
xlink:arcrole="[0..1]"
xlink:title="[0..1]"
xlink:show="[0..1]"
xlink:actuate="[0..1]"
nilReason="gml:NilReasonType [0..1]"
gml:remoteSchema="[0..1]">
Start Sequence [0..1]
<gml:AbstractFeature> ... </gml:AbstractFeature> [1]
End Sequence
</...>
Schema Component Representation
<complexType name="ProcedurePropertyType">
<sequence minOccurs="0">
<element ref="gml:AbstractFeature"/>
</sequence>
<attributeGroup ref="gml:OwnershipAttributeGroup"/>
<attributeGroup ref="gml:AssociationAttributeGroup"/>
</complexType>
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Complex Type: ResultType

Super-types:None
Sub-types:None
NameResultType
Abstractno
XML Instance Representation
<...
owns="boolean [0..1]"
xlink:type="simple [0..1]"
xlink:href="[0..1]"
xlink:role="[0..1]"
xlink:arcrole="[0..1]"
xlink:title="[0..1]"
xlink:show="[0..1]"
xlink:actuate="[0..1]"
nilReason="gml:NilReasonType [0..1]"
gml:remoteSchema="[0..1]">
Start Sequence [0..1]
<gml:AbstractObject> ... </gml:AbstractObject> [1]
End Sequence
</...>
Schema Component Representation
<complexType name="ResultType">
<sequence minOccurs="0">
<element ref="gml:AbstractObject"/>
</sequence>
<attributeGroup ref="gml:OwnershipAttributeGroup"/>
<attributeGroup ref="gml:AssociationAttributeGroup"/>
</complexType>
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Complex Type: TargetPropertyType

Super-types:None
Sub-types:None
NameTargetPropertyType
Abstractno
XML Instance Representation
<...
owns="boolean [0..1]"
xlink:type="simple [0..1]"
xlink:href="[0..1]"
xlink:role="[0..1]"
xlink:arcrole="[0..1]"
xlink:title="[0..1]"
xlink:show="[0..1]"
xlink:actuate="[0..1]"
nilReason="gml:NilReasonType [0..1]"
gml:remoteSchema="[0..1]">
Start Choice [0..1]
<gml:AbstractFeature> ... </gml:AbstractFeature> [1]
<gml:AbstractGeometry> ... </gml:AbstractGeometry> [1]
End Choice
</...>
Schema Component Representation
<complexType name="TargetPropertyType">
<choice minOccurs="0">
<element ref="gml:AbstractFeature"/>
<element ref="gml:AbstractGeometry"/>
</choice>
<attributeGroup ref="gml:OwnershipAttributeGroup"/>
<attributeGroup ref="gml:AssociationAttributeGroup"/>
</complexType>
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Legend

Complex Type:

Schema Component Type

AusAddress

Schema Component Name
Super-types:Address < AusAddress (by extension)
Sub-types:
  • QLDAddress (by restriction)
If this schema component is a type definition, its type hierarchy is shown in a gray-bordered box.
NameAusAddress
Abstractno
The table above displays the properties of this schema component.
XML Instance Representation
<... country="Australia">
<unitNo> string </unitNo> [0..1]
<houseNo> string </houseNo> [1]
<street> string </street> [1]
Start Choice[1]
<city> string </city> [1]
<town> string </town> [1]
End Choice
<state> AusStates </state> [1]
<postcode> string <<pattern = [1-9][0-9]{3}>> </postcode> [1]?
</...>

The XML Instance Representation table above shows the schema component's content as an XML instance.

Schema Component Representation
<complexTypename="AusAddress">
<complexContent>
<extensionbase="Address">
<sequence>
<elementname="state" type="AusStates"/>
<elementname="postcode">
<simpleType>
<restrictionbase="string">
<patternvalue="[1-9][0-9]{3}"/>
</restriction>
</simpleType>
</element>
</sequence>
<attributename="country" type="string" fixed="Australia"/>
</extension>
</complexContent>
</complexType>
The Schema Component Representation table above displays the underlying XML representation of the schema component. (Annotations are not shown.)
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Glossary

Abstract (Applies to complex type definitions and element declarations). An abstract element or complex type cannot used to validate an element instance. If there is a reference to an abstract element, only element declarations that can substitute the abstract element can be used to validate the instance. For references to abstract type definitions, only derived types can be used.

All Model Group Child elements can be provided in any order in instances. See: http://www.w3.org/TR/xmlschema-1/#element-all.

Choice Model Group Only one from the list of child elements and model groups can be provided in instances. See: http://www.w3.org/TR/xmlschema-1/#element-choice.

Collapse Whitespace Policy Replace tab, line feed, and carriage return characters with space character (Unicode character 32). Then, collapse contiguous sequences of space characters into single space character, and remove leading and trailing space characters.

Disallowed Substitutions (Applies to element declarations). If substitution is specified, then substitution group members cannot be used in place of the given element declaration to validate element instances. If derivation methods, e.g. extension, restriction, are specified, then the given element declaration will not validate element instances that have types derived from the element declaration's type using the specified derivation methods. Normally, element instances can override their declaration's type by specifying an xsi:type attribute.

Key Constraint Like Uniqueness Constraint, but additionally requires that the specified value(s) must be provided. See: http://www.w3.org/TR/xmlschema-1/#cIdentity-constraint_Definitions.

Key Reference Constraint Ensures that the specified value(s) must match value(s) from a Key Constraint or Uniqueness Constraint. See: http://www.w3.org/TR/xmlschema-1/#cIdentity-constraint_Definitions.

Model Group Groups together element content, specifying the order in which the element content can occur and the number of times the group of element content may be repeated. See: http://www.w3.org/TR/xmlschema-1/#Model_Groups.

Nillable (Applies to element declarations). If an element declaration is nillable, instances can use the xsi:nil attribute. The xsi:nil attribute is the boolean attribute, nil, from the http://www.w3.org/2001/XMLSchema-instance namespace. If an element instance has an xsi:nil attribute set to true, it can be left empty, even though its element declaration may have required content.

Notation A notation is used to identify the format of a piece of data. Values of elements and attributes that are of type, NOTATION, must come from the names of declared notations. See: http://www.w3.org/TR/xmlschema-1/#cNotation_Declarations.

Preserve Whitespace Policy Preserve whitespaces exactly as they appear in instances.

Prohibited Derivations (Applies to type definitions). Derivation methods that cannot be used to create sub-types from a given type definition.

Prohibited Substitutions (Applies to complex type definitions). Prevents sub-types that have been derived using the specified derivation methods from validating element instances in place of the given type definition.

Replace Whitespace Policy Replace tab, line feed, and carriage return characters with space character (Unicode character 32).

Sequence Model Group Child elements and model groups must be provided in the specified order in instances. See: http://www.w3.org/TR/xmlschema-1/#element-sequence.

Substitution Group Elements that are members of a substitution group can be used wherever the head element of the substitution group is referenced.

Substitution Group Exclusions (Applies to element declarations). Prohibits element declarations from nominating themselves as being able to substitute a given element declaration, if they have types that are derived from the original element's type using the specified derivation methods.

Target Namespace The target namespace identifies the namespace that components in this schema belongs to. If no target namespace is provided, then the schema components do not belong to any namespace.

Uniqueness Constraint Ensures uniqueness of an element/attribute value, or a combination of values, within a specified scope. See: http://www.w3.org/TR/xmlschema-1/#cIdentity-constraint_Definitions.

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