Use Case ONTO19: Within Distance

[ar-chad]

Use Case ONTO18

Within Distance

As a GeoSPARQL data user I would like to know if geometries are within a specific distance from each other.

This function is different to the existing geof:distance and geof:metricDistance functions in that it returns boolean and not actual distance. It does not return distance between geometries, but the answer to a question if the distance between them does not exceed a specified value.

Function signature:

withinDistance(geometry: ogc:geomLiteral, geometry: ogc:geomLiteral, xsd:double): xsd:boolean

Actor: GeoSPARQL data user (human or software agent querying RDF dataset with GeoSPARQL)

Preconditions

Features and Geometries with 2D and 3D representations are present in a dataset to be queried. The within distance function is discoverable.

Postconditions

A SPARQL query can be executed that includes a function to check whether two geometries are within specified distance to each other. The results of the query are known to be true or false in 2D and 3D.

Steps

Actor: discovers within distance function implemented by the system
Actor: executes a SPARQL query with within distance function with two geometries and distance value as arguments.
System: returns a SPARQL result with a boolean value.

[ar-chad]

Closed as a duplicate of DWithin function #536