org.opengis.coverage
Interface DiscreteGridPointCoverage

Show UML class diagram

All Superinterfaces:

Coverage, DiscreteCoverage

@UML(identifier="CV_DiscreteGridPointCoverage",
     specification=ISO_19123)
public interface DiscreteGridPointCoverage
extends DiscreteCoverage

A discrete coverage with a domain defined as a set of grid points that are associated with records of feature attribute values through a grid values matrix.

DiscreteGridPointCoverage inherits the elements and the operations locate, find, and list, from DiscreteCoverage, with the restriction that the associated geometry-value pairs and those returned by the operations shall be limited to (grid point)-(value) pairs. The elements may be generated from the grid values matrix through the value assignment. The inherited operations evaluate and evaluateInverse use grid values matrix to assign values to the geometry-value pairs.

Since:

GeoAPI 2.1

TODO:

Should we restrict DomainObject to GridPoint as well? It sound like a logical consequence of GridPointValuePair restriction., Should we move this interface to org.opengis.coverage.grid as all the other grid interfaces, or should it remain in org.opengis.coverage to follow the ordering in ISO19123?, What should be the behavior of Coverage.evaluate(DirectPosition) when the position is not exactly on a grid point? Current proposal is to return an empty set.

Method Summary

Set<GridPoint>	evaluateInverse(Record v) Returns a set of grid points for the specified record of feature attribute values.
GridPointValuePair	find(DirectPosition p) Returns the nearest point-value pair from the specified direct position.
List<GridPointValuePair>	find(DirectPosition p, int limit) Returns the sequence of point-value pairs that include the domain objects nearest to the direct position and their distances from the direction position.
Set<GridPointValuePair>	getElements() Returns the set of point-value pairs included in this coverage.
GridValuesMatrix	getValueAssignment() Links this discrete grid point coverage to the grid values matrix for which it is an evaluator.
Set<GridPointValuePair>	list() Returns the dictionary of point-value pairs that contain the objects in the domain of the coverage each paired with its record of feature attribute values.
Set<GridPointValuePair>	locate(DirectPosition p) Returns the set of point-value pairs that include the domain objects containing the specified direct position.
GridPointValuePair	point(GridCoordinates g) Uses data from the associated grid values matrix to construct and return the grid point value pair associated with the specified grid position.
Set<GridPointValuePair>	select(Geometry s, Period t) Returns the set of point-value pairs that contain domain objects that lie within the specified geometry and period.

Methods inherited from interface DiscreteCoverage

evaluate

Methods inherited from interface Coverage

evaluate, evaluate, evaluate, evaluate, evaluate, evaluate, getCommonPointRule, getCoordinateReferenceSystem, getDomainElements, getDomainExtents, getEnvelope, getNumSampleDimensions, getRangeElements, getRangeType, getRenderableImage, getSampleDimension, getSources

Method Detail

getElements

@UML(identifier="element",
     obligation=OPTIONAL,
     specification=ISO_19123)
Set<GridPointValuePair> getElements()

Returns the set of point-value pairs included in this coverage.

Specified by:

getElements in interface DiscreteCoverage

Returns:

The set of geometry-value pairs, or null.

getValueAssignment

@UML(identifier="valueAssignment",
     obligation=MANDATORY,
     specification=ISO_19123)
GridValuesMatrix getValueAssignment()

Links this discrete grid point coverage to the grid values matrix for which it is an evaluator.

Returns:

The underlying grid values matrix.

locate

@UML(identifier="locate",
     obligation=OPTIONAL,
     specification=ISO_19123)
Set<GridPointValuePair> locate(DirectPosition p)

Returns the set of point-value pairs that include the domain objects containing the specified direct position.

Specified by:

locate in interface DiscreteCoverage

Parameters:

p - The position where to search for geometry-value pairs.

Returns:

geometry-value pairs, or null.

list

@UML(identifier="list",
     obligation=MANDATORY,
     specification=ISO_19123)
Set<GridPointValuePair> list()

Returns the dictionary of point-value pairs that contain the objects in the domain of the coverage each paired with its record of feature attribute values.

Specified by:

list in interface Coverage

Returns:

The geometry-value pairs.

select

@UML(identifier="select",
     obligation=MANDATORY,
     specification=ISO_19123)
Set<GridPointValuePair> select(Geometry s,
                                                                                      Period t)

Returns the set of point-value pairs that contain domain objects that lie within the specified geometry and period. If s is null, the operation shall return all point-value pairs that contain domain objects within t. If the value of t is null, the operation shall return all point-value pair that contain domain objects within s.

Specified by:

select in interface Coverage

Parameters:

s - The spatial component.

t - The temporal component.

Returns:

The values in the given spatio-temporal domain.

find

@UML(identifier="find",
     obligation=MANDATORY,
     specification=ISO_19123)
List<GridPointValuePair> find(DirectPosition p,
                                                                                     int limit)

Returns the sequence of point-value pairs that include the domain objects nearest to the direct position and their distances from the direction position. The sequence shall be ordered by distance from the direct position, beginning with the record containing the domain object nearest to the direct position. The length of the sequence (the number of point-value pairs returned) shall be no greater than the number specified by the parameter limit. The default shall be to return a single point-value pair. The operation shall return a warning if the last domain object in the sequence is at a distance from the direct position equal to the distance of other domain objects that are not included in the sequence.

Specified by:

find in interface Coverage

Parameters:

p - The search position.

limit - The maximal size of the list to be returned.

Returns:

The geometry-value pairs nearest to the given position.

find

@UML(identifier="find",
     obligation=MANDATORY,
     specification=ISO_19123)
GridPointValuePair find(DirectPosition p)

Returns the nearest point-value pair from the specified direct position. This is a shortcut for find(p,1).

Specified by:

find in interface Coverage

Parameters:

p - The search position.

Returns:

The geometry-value pair nearest to the given position.

point

@UML(identifier="point",
     obligation=MANDATORY,
     specification=ISO_19123)
GridPointValuePair point(GridCoordinates g)

Uses data from the associated grid values matrix to construct and return the grid point value pair associated with the specified grid position.

Parameters:

g - The position where to search for a value.

Returns:

The point and value at the specified position.

evaluateInverse

@UML(identifier="evaluateInverse",
     obligation=MANDATORY,
     specification=ISO_19123)
Set<GridPoint> evaluateInverse(Record v)

Returns a set of grid points for the specified record of feature attribute values. Normally, this method returns the set of points in the domain that are associated with values equal to those in the input record. However, the operation may return other points derived from those in the domain, as specified by the application schema.

Specified by:

evaluateInverse in interface Coverage

Specified by:

evaluateInverse in interface DiscreteCoverage

Parameters:

v - The feature attributes.

Returns:

The domain where the attributes are found.