Interface DiscretePointCoverage

  • All Superinterfaces:
    Coverage, DiscreteCoverage

    @UML(identifier="CV_DiscretePointCoverage",
         specification=ISO_19123)
    public interface DiscretePointCoverage
    extends DiscreteCoverage
    A discrete coverage characterized by a finite domain consisting of points. Generally, the domain is a set of irregularly distributed points. However, the principal use of discrete point coverages is to provide a basis for continuous coverage functions, where the evaluation of the continuous coverage function is accomplished by interpolation between the points of the discrete point coverage. Most interpolation algorithms depend upon a structured pattern of spatial relationships between the points. This requires either that the points in the spatial domain of the discrete point coverage be arranged in a regular way, or that the spatial domain of the continuous coverage be partitioned in a regular way in relation to the points of the discrete point coverage. Grid coverages employ the first method; Thiessen polygon coverages and TIN's employ the second.

    EXAMPLE: A set of hydrographic soundings is a discrete point coverage.

    DiscretePointCoverage 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 point-value pairs.

    Since:
    GeoAPI 2.1
    • Method Detail

      • getElements

        @UML(identifier="element",
             obligation=OPTIONAL,
             specification=ISO_19123)
        Set<PointValuePair> 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.
      • locate

        @UML(identifier="locate",
             obligation=OPTIONAL,
             specification=ISO_19123)
        Set<PointValuePair> 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<PointValuePair> 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<PointValuePair> 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<PointValuePair> 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)
        PointValuePair 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.