value.xsd
Copyright (c) 2002 OGC, All Rights Reserved.
GML conformant schema for Observed Values in which the
* scalar Value types have their values recorded in simpleContent elements
* complex Value types are built recursively
Compact "list" types are also provided.
2002-02-26 added ValueRange
2002-03-11 properties based on AssociationType, moved *OrNull and *List types to gmlBase
2002-03-14 removed observable attribute ...
2002-03-15 put it back as a local attribute
2002-03-28 create referenceSystem attribute group.
2002-04-10 remove Position and OrderedCategory components -
the semantic that this value is on an Interval/Ordinal scale
are provided in the definition of the reference system
2002-04-10 re-define Observed(Value)Types as extensions of basic types
2002-04-12 define Value group
All are unified into a single hierarchy using substitutionGroups using some abstract head elements
head Value element is abstract -
this means that potentially either simpleContent or complexContent elements can substitute
Should be type="xs:anySimpleType" except MSXML does not recognise anySimpleType
Use these elements for a compact encoding of arrays of scalar values
true/false or 1/0. Adds an observable parameter for weak semantic typing.
Term from a controlled codeSpace.
Adds an observable parameter to NominalType for weak semantic typing.
Number with a scale.
Adds an observable parameter to MeasureType for weak semantic typing.
The name Quantity is used since this conforms with general usage.
Integer amount with no scale.
Adds an observable parameter for weak semantic typing.
A CompositeValue is conceptually a single Value,
usually collected by some complex sensor or sensor package,
but represented by several components - e.g. Vector, Tensor.
The observable indicates the type of the complex value as a whole.
The components will also have an observable to indicate their types.
Vector or tensor value
ValueCollection is built up from other Values. No other restrictions. No implications for ordering.
A Value Collection is an arbitrary combination of values
ValueArray is a collection of homogeneous values.
The member values may be composite, collections or arrays.
Since the members are homgeneous, the common parameters can be attached to the container, and inherited by the members:
referenceSystem - choose the appropriate one for the type of the members;
observable - this is implicitly inherited by the immediate child member values,
though if the children are themselves composite values then their children require their own observables for disambiguation.
ValueArray may not carry both a reference to a codeSpace and a uom
All members of must be of the same type
All members of must be of the same type
A Value Array is used for homogeneous arrays of CompositeValues and other ValueCollections.
_ValueList is preferred for arrays of Scalar Values since this is more efficient.
Utility element to store 2-point ranges
add "axis" attribute to indicate an index or ordering for vector and tensor values,
in cases where the "observable" on the component value is insufficient
Use this to provide a gloss on the measurement(s)