OGC 08-094r1 SWE Common Data Model
swe:value Underwater camera
swe:value swe:AllowedTokens
swe:constraint swe:Category
In this example, the values allowed by the code space OWL ontology located at http:mmisw.orgontbodcinstrument
are further restricted by allowing only three of its members.
This element can also be used to specify a constraint with a regular expression pattern. This is shown below with a model number example using a “Text” element:
swe:Text definition
= http:mmisw.orgontmmideviceModelID
swe:label Model Number
swe:label swe:constraint
swe:AllowedTokens swe:pattern
[0-9][A-Z]{3}[0-9]{2}S1 swe:pattern
swe:AllowedTokens swe:constraint
swe:Text
The pattern shall follow the unicode regular expression syntax described in Unicode Technical Std 18. This is the same syntax as the one used by the XML Schema
specification.
Requirement
http:www.opengis.netspecSWE2.0reqxsd-simple-componentsunicode-regex-valid
Req 66. The “pattern” child element of the “AllowedTokens” element shall be a
regular expression valid with respect to Unicode Technical Standard 18, Version 13.
8.1.16 AllowedValues Element
The “AllowedValues” element is the XML schema implementation of the “AllowedValues” UML class defined in clause 7.2.18. The schema snippet for this
element and its corresponding complex type is shown below:
element name
= AllowedValues
substitutionGroup =
swe:AbstractSWE type
= swe:AllowedValuesType
complexType name
= AllowedValuesType
complexContent extension
base =
swe:AbstractSWEType sequence
element name
= value
type =
double minOccurs
= maxOccurs
= unbounded
element name
= interval
type =
swe:RealPair minOccurs
= maxOccurs
= unbounded
element name
= significantFigures
type =
integer minOccurs
= sequence
extension complexContent
complexType
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Copyright © 2011 Open Geospatial Consortium
SWE Common Data Model OGC 08-094r1
This element is used to specify numerical constraints for the “Count” and “Quantity” elements and the corresponding range components. The XML snippet below illustrates
how to constrain an angular value to the -180180 degrees domain:
swe:Quantity definition
= http:sweet.jpl.nasa.gov2.0spaceDirection.owlAngle
swe:label Planar Angle
swe:label swe:uom
code =
deg swe:constraint
swe:AllowedValues swe:interval
-180 +180 swe:interval
swe:AllowedValues swe:constraint
swe:Quantity
Several intervals can be specified to generate holes with forbidden values. Using several intervals means that the value is constrained to be within one of the intervals:
swe:AllowedValues swe:interval
-INF -20 swe:interval
swe:interval 20 50
swe:interval swe:interval
60 INF swe:interval
swe:AllowedValues
Note that the –Infinity and +Infinity are allowed in order to specify unbounded intervals. The above example indicates that the value must be either less than or equal to -20,
between 20 and 50 included, or greater than or equal to 60. Intervals specified with this element are always inclusive and should not overlap.
Allowed values can also be enumerated as shown in the example below:
swe:Count definition
= http:www.opengis.netdefpropertyOGC0NumberOfPixels
swe:label Image Width
swe:label swe:constraint
swe:AllowedValues swe:value
256 swe:value
swe:value 512
swe:value swe:value
1024 swe:value
swe:AllowedValues swe:constraint
swe:Count
Several allowed intervals and values can also be combined to express a complex constraint even though this is rarely used in practice:
swe:AllowedValues swe:value
5 swe:value
swe:value 10
swe:value swe:interval
20 30 swe:interval
swe:interval 40 60
swe:interval swe:AllowedValues
In the above example, the actual value must be 5, or 10, or between 20 and 30 included, or between 40 and 60 included. All numbers used within “interval” and “value” elements
shall be expressed in the same unit as the enclosing data component Req 36.
Copyright © 2011 Open Geospatial Consortium
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