point_in_ranked_polygon - ObjectVision/GeoDMS GitHub Wiki

Geometric functions point_in_ranked_polygon

• point_in_ranked_polygon(point_data_item, polygon_data_item, rank_data_item)

point_in_ranked_polygon(point_data_item, polygon_data_item, rank_data_item) results for each point of the point_data_item in a relation towards the domain unit of the polygon_data_item in which the point is located.

The resulting values unit is the domain unit of the polygon_data_item.

If a point is not located in any polygon, the function results in a null value. If a point is located in multiple polygons (the red point in the image), the function results in the polygon with the lowest rank_data_item value.

The rank_data_item argument is used to make an explicit choice for a polygon, if a point is located in multiple polygons. Therefore the rank values need to distinguish the different polygons. If a constant is used as rank value, the point_in_ranked_polygon results in the same values as the point_in_polygon function.

• a data item point_data_item with Point value type
• a data item polygon_data_item with composition type type polygon and Point value type
• a data item rank_data_item with a uint8, (u)int32, float32 or float64 value type

8.036

O(n log p + n * k) where n = number of points, p = number of polygons, and k = average polygon complexity. Similar to point_in_polygon, but additionally considers ranking when multiple polygons contain a point.

attribute<city> city_rel (ADomain) := point_in_ranked_polygon(Adomain/point, city/geometry, city/rank);

ADomain, nr of rows = 5

domain City, nr of rows = 7

• point_in_polygon
• point_in_all_polygons