# gml:dictionaryEntry

This property element contains or refers to the definitions which are members of a dictionary. The content model follows the standard GML property pattern, so a gml:dictionaryEntry may either contain or refer to a single gml:Definition. Since gml:Dictionary is substitutable for gml:Definition, the content of an entry may itself be a lower level dictionary. Note that if the value is provided by reference, this definition does not carry a handle (gml:id) in this context, so does not allow external references to this specific definition in this context. When used in this way the referenced definition will usually be in a dictionary in the same XML document.

## Element information

Namespace: http://www.opengis.net/gml/3.2

Schema document: external/ogc/gml/3.2.1/dictionary.xsd

Type: gml:DictionaryEntryType

Properties: Global, Qualified

## Content

- Choice [0..1]
- gml:DefinitionThe basic gml:Definition element specifies a definition, which can be included in or referenced by a dictionary. The content model for a generic definition is a derivation from gml:AbstractGMLType. The gml:description property element shall hold the definition if this can be captured in a simple text string, or the gml:descriptionReference property element may carry a link to a description elsewhere. The gml:identifier element shall provide one identifier identifying this definition. The identifier shall be unique within the dictionaries using this definition. The gml:name elements shall provide zero or more terms and synonyms for which this is the definition. The gml:remarks element shall be used to hold additional textual information that is not conceptually part of the definition but is useful in understanding the definition.
- gml:PassThroughOperationgml:PassThroughOperation is a pass-through operation specifies that a subset of a coordinate tuple is subject to a specific coordinate operation. The modifiedCoordinate property elements are an ordered sequence of positive integers defining the positions in a coordinate tuple of the coordinates affected by this pass-through operation. The AggregationAttributeGroup should be used to specify that the modifiedCoordinate elements are ordered.
- gml:Conversiongml:Conversion is a concrete operation on coordinates that does not include any change of Datum. The best-known example of a coordinate conversion is a map projection. The parameters describing coordinate conversions are defined rather than empirically derived. Note that some conversions have no parameters. This concrete complex type can be used without using a GML Application Schema that defines operation-method-specialized element names and contents, especially for methods with only one Conversion instance. The usesValue property elements are an unordered list of composition associations to the set of parameter values used by this conversion operation.
- gml:Transformationgml:Transformation is a concrete object element derived from gml:GeneralTransformation (13.6.2.13). This concrete object can be used for all operation methods, without using a GML Application Schema that defines operation-method-specialized element names and contents, especially for methods with only one Transformation instance. The parameterValue elements are an unordered list of composition associations to the set of parameter values used by this conversion operation.
- gml:ConcatenatedOperation
- gml:OperationMethodgml:OperationMethod is a method (algorithm or procedure) used to perform a coordinate operation. Most operation methods use a number of operation parameters, although some coordinate conversions use none. Each coordinate operation using the method assigns values to these parameters. The parameter elements are an unordered list of associations to the set of operation parameters and parameter groups used by this operation method.
- gml:OperationParametergml:OperationParameter is the definition of a parameter used by an operation method. Most parameter values are numeric, but other types of parameter values are possible. This complex type is expected to be used or extended for all operation methods, without defining operation-method-specialized element names.
- gml:OperationParameterGroupgml: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 generalOperationParameter elements are an unordered list of associations to the set of operation parameters that are members of this group.
- gml:CoordinateSystemAxisgml:CoordinateSystemAxis is a definition of a coordinate system axis.
- gml:EllipsoidalCSgml:EllipsoidalCS is a two- or three-dimensional coordinate system in which position is specified by geodetic latitude, geodetic longitude, and (in the three-dimensional case) ellipsoidal height. An EllipsoidalCS shall have two or three gml:axis property elements; the number of associations shall equal the dimension of the CS.
- gml:CartesianCSgml:CartesianCS is a 1-, 2-, or 3-dimensional coordinate system. In the 1-dimensional case, it contains a single straight coordinate axis. In the 2- and 3-dimensional cases gives the position of points relative to orthogonal straight axes. In the multi-dimensional case, all axes shall have the same length unit of measure. A CartesianCS shall have one, two, or three gml:axis property elements.
- gml:VerticalCSgml:VerticalCS is a one-dimensional coordinate system used to record the heights or depths of points. Such a coordinate system is usually dependent on the Earth's gravity field, perhaps loosely as when atmospheric pressure is the basis for the vertical coordinate system axis. A VerticalCS shall have one gml:axis property element.
- gml:TimeCSgml:TimeCS is a one-dimensional coordinate system containing a time axis, used to describe the temporal position of a point in the specified time units from a specified time origin. A TimeCS shall have one gml:axis property element.
- gml:LinearCSgml:LinearCS is a one-dimensional coordinate system that consists of the points that lie on the single axis described. The associated coordinate is the distance – with or without offset – from the specified datum to the point along the axis. A LinearCS shall have one gml:axis property element.
- gml:UserDefinedCSgml:UserDefinedCS is a two- or three-dimensional coordinate system that consists of any combination of coordinate axes not covered by any other coordinate system type. A UserDefinedCS shall have two or three gml:axis property elements; the number of property elements shall equal the dimension of the CS.
- gml:SphericalCSgml:SphericalCS is a three-dimensional coordinate system with one distance measured from the origin and two angular coordinates. A SphericalCS shall have three gml:axis property elements.
- gml:PolarCSgml:PolarCS ia s two-dimensional coordinate system in which position is specified by the distance from the origin and the angle between the line from the origin to a point and a reference direction. A PolarCS shall have two gml:axis property elements.
- gml:CylindricalCSgml:CylindricalCS is a three-dimensional coordinate system consisting of a polar coordinate system extended by a straight coordinate axis perpendicular to the plane spanned by the polar coordinate system. A CylindricalCS shall have three gml:axis property elements.
- gml:AffineCSgml:AffineCS is a two- or three-dimensional coordinate system with straight axes that are not necessarily orthogonal. An AffineCS shall have two or three gml:axis property elements; the number of property elements shall equal the dimension of the CS.
- gml:TemporalCS
- gml:ObliqueCartesianCS
- gml:GeodeticDatumgml:GeodeticDatum is a geodetic datum defines the precise location and orientation in 3-dimensional space of a defined ellipsoid (or sphere), or of a Cartesian coordinate system centered in this ellipsoid (or sphere).
- gml:EngineeringDatumgml:EngineeringDatum defines the origin of an engineering coordinate reference system, and is used in a region around that origin. This origin may be fixed with respect to the earth (such as a defined point at a construction site), or be a defined point on a moving vehicle (such as on a ship or satellite).
- gml:ImageDatumgml:ImageDatum defines the origin of an image coordinate reference system, and is used in a local context only. For an image datum, the anchor definition is usually either the centre of the image or the corner of the image. For more information, see ISO 19111 B.3.5.
- gml:VerticalDatumgml:VerticalDatum is a textual description and/or a set of parameters identifying a particular reference level surface used as a zero-height surface, including its position with respect to the Earth for any of the height types recognized by this International Standard.
- gml:TemporalDatumA gml:TemporalDatum defines the origin of a Temporal Reference System. This type omits the "anchorDefinition" and "realizationEpoch" elements and adds the "origin" element with the dateTime type.
- gml:EllipsoidA gml:Ellipsoid is a geometric figure that may be used to describe the approximate shape of the earth. In mathematical terms, it is a surface formed by the rotation of an ellipse about its minor axis.
- gml:PrimeMeridianA gml:PrimeMeridian defines the origin from which longitude values are determined. The default value for the prime meridian gml:identifier value is "Greenwich".
- gml:DefinitionCollection
- gml:DefinitionProxy
- gml:DictionarySets of definitions may be collected into dictionaries or collections. A gml:Dictionary is a non-abstract collection of definitions. The gml:Dictionary content model adds a list of gml:dictionaryEntry properties that contain or reference gml:Definition objects. A database handle (gml:id attribute) is required, in order that this collection may be referred to. The standard gml:identifier, gml:description, gml:descriptionReference and gml:name properties are available to reference or contain more information about this dictionary. The gml:description and gml:descriptionReference property elements may be used for a description of this dictionary. The derived gml:name element may be used for the name(s) of this dictionary. for remote definiton references gml:dictionaryEntry shall be used. If a Definition object contained within a Dictionary uses the descriptionReference property to refer to a remote definition, then this enables the inclusion of a remote definition in a local dictionary, giving a handle and identifier in the context of the local dictionary.
- gmx:CodeListDictionary
- gml:ProjectedCRSgml:ProjectedCRS is a 2D coordinate reference system used to approximate the shape of the earth on a planar surface, but in such a way that the distortion that is inherent to the approximation is carefully controlled and known. Distortion correction is commonly applied to calculated bearings and distances to produce values that are a close match to actual field values.
- gml:DerivedCRSgml:DerivedCRS is a single coordinate reference system that is defined by its coordinate conversion from another single coordinate reference system known as the base CRS. The base CRS can be a projected coordinate reference system, if this DerivedCRS is used for a georectified grid coverage as described in ISO 19123, Clause 8.
- gml:GeodeticCRS
- gml:VerticalCRSgml:VerticalCRS is a 1D coordinate reference system used for recording heights or depths. Vertical CRSs make use of the direction of gravity to define the concept of height or depth, but the relationship with gravity may not be straightforward. By implication, ellipsoidal heights (h) cannot be captured in a vertical coordinate reference system. Ellipsoidal heights cannot exist independently, but only as an inseparable part of a 3D coordinate tuple defined in a geographic 3D coordinate reference system.
- gml:EngineeringCRSgml:EngineeringCRS is a contextually local coordinate reference system which can be divided into two broad categories: - earth-fixed systems applied to engineering activities on or near the surface of the earth; - CRSs on moving platforms such as road vehicles, vessels, aircraft, or spacecraft, see ISO 19111 8.3.
- gml:ImageCRSgml:ImageCRS is an engineering coordinate reference system applied to locations in images. Image coordinate reference systems are treated as a separate sub-type because the definition of the associated image datum contains two attributes not relevant to other engineering datums.
- gml:TemporalCRSgml:TemporalCRS is a 1D coordinate reference system used for the recording of time.
- gml:GeographicCRS
- gml:GeocentricCRS
- gml:CompoundCRSgml:CompundCRS is a coordinate reference system describing the position of points through two or more independent coordinate reference systems. It is associated with a non-repeating sequence of two or more instances of SingleCRS.
- gml:TimeReferenceSystemA reference system is characterized in terms of its domain of validity: the spatial and temporal extent over which it is applicable. The basic GML element for temporal reference systems is gml:TimeReferenceSystem. Its content model extends gml:DefinitionType with one additional property, gml:domainOfValidity.
- gml:TimeCoordinateSystemA temporal coordinate system shall be based on a continuous interval scale defined in terms of a single time interval. The differences to ISO 19108 TM_CoordinateSystem are: - the origin is specified either using the property gml:originPosition whose value is a direct time position, or using the property gml:origin whose model is gml:TimeInstantPropertyType; this permits more flexibility in representation and also supports referring to a value fixed elsewhere; - the interval uses gml:TimeIntervalLengthType.
- gml:TimeCalendarA calendar is a discrete temporal reference system that provides a basis for defining temporal position to a resolution of one day. gml:TimeCalendar adds one property to those inherited from gml:TimeReferenceSystem. A gml:referenceFrame provides a link to a gml:TimeCalendarEra that it uses. A gml:TimeCalendar may reference more than one calendar era. The referenceFrame element follows the standard GML property model, allowing the association to be instantiated either using an inline description using the gml:TimeCalendarEra element, or a link to a gml:TimeCalendarEra which is explicit elsewhere.
- gml:TimeClockA clock provides a basis for defining temporal position within a day. A clock shall be used with a calendar in order to provide a complete description of a temporal position within a specific day. gml:TimeClock adds the following properties to those inherited from gml:TimeReferenceSystemType: - gml:referenceEvent is the name or description of an event, such as solar noon or sunrise, which fixes the position of the base scale of the clock. - gml:referenceTime specifies the time of day associated with the reference event expressed as a time of day in the given clock. The reference time is usually the origin of the clock scale. - gml:utcReference specifies the 24 hour local or UTC time that corresponds to the reference time. - gml:dateBasis contains or references the calendars that use this clock.
- gml:TimeOrdinalReferenceSystemIn some applications of geographic information — such as geology and archaeology — relative position in time is known more precisely than absolute time or duration. The order of events in time can be well established, but the magnitude of the intervals between them cannot be accurately determined; in such cases, the use of an ordinal temporal reference system is appropriate. An ordinal temporal reference system is composed of a sequence of named coterminous eras, which may in turn be composed of sequences of member eras at a finer scale, giving the whole a hierarchical structure of eras of verying resolution. An ordinal temporal reference system whose component eras are not further subdivided is effectively a temporal topological complex constrained to be a linear graph. An ordinal temporal reference system some or all of whose component eras are subdivided is effectively a temporal topological complex with the constraint that parallel branches may only be constructed in pairs where one is a single temporal ordinal era and the other is a sequence of temporal ordinal eras that are called "members" of the "group". This constraint means that within a single temporal ordinal reference system, the relative position of all temporal ordinal eras is unambiguous. The positions of the beginning and end of a given era may calibrate the relative time scale. gml:TimeOrdinalReferenceSystem adds one or more gml:component properties to the generic temporal reference system model.
- gml:UnitDefinitionA gml:UnitDefinition is a general definition of a unit of measure. This generic element is used only for units for which no relationship with other units or units systems is known. The content model of gml:UnitDefinition adds three additional properties to gml:Definition, gml:quantityType, gml:quantityTypeReference and gml:catalogSymbol. The gml:catalogSymbol property optionally gives the short symbol used for this unit. This element is usually used when the relationship of this unit to other units or units systems is unknown.
- gml:BaseUnitA base unit is a unit of measure that cannot be derived by combination of other base units within a particular system of units. For example, in the SI system of units, the base units are metre, kilogram, second, Ampere, Kelvin, mole, and candela, for the physical quantity types length, mass, time interval, electric current, thermodynamic temperature, amount of substance and luminous intensity, respectively. gml:BaseUnit extends generic gml:UnitDefinition with the property gml:unitsSystem, which carries a reference to the units system to which this base unit is asserted to belong.
- gml:DerivedUnitDerived units are defined by combination of other units. Derived units are used for quantities other than those corresponding to the base units, such as hertz (s-1) for frequency, Newton (kg.m/s2) for force. Derived units based directly on base units are usually preferred for quantities other than the fundamental quantities within a system. If a derived unit is not the preferred unit, the gml:ConventionalUnit element should be used instead. The gml:DerivedUnit extends gml:UnitDefinition with the property gml:derivationUnitTerms.
- gml:ConventionalUnitConventional units that are neither base units nor defined by direct combination of base units are used in many application domains. For example electronVolt for energy, feet and nautical miles for length. In most cases there is a known, usually linear, conversion to a preferred unit which is either a base unit or derived by direct combination of base units. The gml:ConventionalUnit extends gml:UnitDefinition with a property that describes a conversion to a preferred unit for this physical quantity. When the conversion is exact, the element gml:conversionToPreferredUnit should be used, or when the conversion is not exact the element gml:roughConversionToPreferredUnit is available. Both of these elements have the same content model. The gml:derivationUnitTerm property defined above is included to allow a user to optionally record how this unit may be derived from other ("more primitive") units.
- gmx:ML_UnitDefinition
- gmx:CodeDefinition

from subst. group gml:Definitionfrom subst. group gml:AbstractCoordinateOperationfrom subst. group gml:AbstractSingleOperationfrom subst. group gml:PassThroughOperationfrom subst. group gml:AbstractGeneralConversionfrom subst. group gml:Conversionfrom subst. group gml:AbstractGeneralTransformationfrom subst. group gml:Transformationfrom subst. group gml:ConcatenatedOperationfrom subst. group gml:OperationMethodfrom subst. group gml:AbstractGeneralOperationParameterfrom subst. group gml:OperationParameterfrom subst. group gml:OperationParameterGroupfrom subst. group gml:CoordinateSystemAxisfrom subst. group gml:AbstractCoordinateSystemfrom subst. group gml:EllipsoidalCSfrom subst. group gml:CartesianCSfrom subst. group gml:VerticalCSfrom subst. group gml:TimeCSfrom subst. group gml:LinearCSfrom subst. group gml:UserDefinedCSfrom subst. group gml:SphericalCSfrom subst. group gml:PolarCSfrom subst. group gml:CylindricalCSfrom subst. group gml:AffineCSfrom subst. group gml:AbstractDatumfrom subst. group gml:GeodeticDatumfrom subst. group gml:EngineeringDatumfrom subst. group gml:ImageDatumfrom subst. group gml:VerticalDatumfrom subst. group gml:TemporalDatumfrom subst. group gml:Ellipsoidfrom subst. group gml:PrimeMeridianfrom subst. group gml:Dictionaryfrom subst. group gmx:CodeListDictionaryfrom subst. group gml:AbstractCRSfrom subst. group gml:AbstractSingleCRSfrom subst. group gml:AbstractGeneralDerivedCRSfrom subst. group gml:ProjectedCRSfrom subst. group gml:DerivedCRSfrom subst. group gml:GeodeticCRSfrom subst. group gml:VerticalCRSfrom subst. group gml:EngineeringCRSfrom subst. group gml:ImageCRSfrom subst. group gml:TemporalCRSfrom subst. group gml:CompoundCRSfrom subst. group gml:TimeReferenceSystemfrom subst. group gml:UnitDefinitionfrom subst. group gml:BaseUnitfrom subst. group gml:DerivedUnitfrom subst. group gml:ConventionalUnitfrom subst. group gmx:CodeDefinition

## Attributes

Name | Occ | Type | Description | Notes |
---|---|---|---|---|

owns | [0..1] | xsd:boolean | Default value is "false". from group gml:OwnershipAttributeGroup | |

xlink:type | [0..1] | xsd:string | Fixed value is "simple". from group xlink:simpleLink | |

xlink:href | [0..1] | xsd:anyURI | from group xlink:simpleLink | |

xlink:role | [0..1] | xsd:anyURI | from group xlink:simpleLink | |

xlink:arcrole | [0..1] | xsd:anyURI | from group xlink:simpleLink | |

xlink:title | [0..1] | xsd:string | from group xlink:simpleLink | |

xlink:show | [0..1] | Anonymous | The 'show' attribute is used to communicate the desired presentation of the ending resource on traversal from the starting resource; it's value should be treated as follows: new - load ending resource in a new window, frame, pane, or other presentation context replace - load the resource in the same window, frame, pane, or other presentation context embed - load ending resource in place of the presentation of the starting resource other - behavior is unconstrained; examine other markup in the link for hints none - behavior is unconstrained | from group xlink:simpleLink |

xlink:actuate | [0..1] | Anonymous | The 'actuate' attribute is used to communicate the desired timing of traversal from the starting resource to the ending resource; it's value should be treated as follows: onLoad - traverse to the ending resource immediately on loading the starting resource onRequest - traverse from the starting resource to the ending resource only on a post-loading event triggered for this purpose other - behavior is unconstrained; examine other markup in link for hints none - behavior is unconstrained | from group xlink:simpleLink |

nilReason | [0..1] | gml:NilReasonType | from group gml:AssociationAttributeGroup | |

gml:remoteSchema | [0..1] | xsd:anyURI | from group gml:AssociationAttributeGroup |

## Used in

- Type gml:DictionaryType (Elements gml:DefinitionCollection, gml:Dictionary)
- Type gmx:CodeListDictionary_Type via extension of gml:DictionaryType (Element gmx:CodeListDictionary)
- Type gmx:ML_CodeListDictionary_Type via extension of gml:DictionaryType (Element gmx:ML_CodeListDictionary)

## Substitution hierarchy

- gml:dictionaryEntry
- can be substituted with gml:definitionMember

## Sample instance

<gml:dictionaryEntry> <gml:Definition 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:remarks>string</gml:remarks> </gml:Definition> </gml:dictionaryEntry>