happign (version 0.3.8)

spatial_predicates: Spatial predicate constructors

Description

These functions create spatial predicates used by get_wfs() to filter features based on their spatial relationship with a reference geometry.

Usage

intersects()
within()
disjoint()
contains()
touches()
crosses()
overlaps()
equals()
bbox()
dwithin(distance, units = "meters")
beyond(distance, units = "meters")
relate(pattern)

Value

A spatial predicate object (used internally by get_wfs()).

Arguments

distance

Numeric distance value (single value).

units

Distance units supported by the WFS server (e.g. "meters", "kilometers").

pattern

A 9-character DE-9IM pattern string.

Details

Predicates describe how geometries should be compared (e.g. intersection, containment, distance-based relations). Users should not construct predicates manually; instead, use the helper functions listed below.

• bbox(): Select features intersecting the bounding box of the reference geometry.

• intersects(): Select features whose geometry intersects the reference geometry.

• disjoint(): Select features whose geometry intersects the reference geometry.

• contains(): Select features that completely contain the reference geometry.

• within(): Select features completely within the reference geometry.

• touches(): Select features that touch the reference geometry at the boundary.

• crosses(): Select features that cross the reference geometry.

• overlaps(): Select features that partially overlap the reference geometry.

• equals(): Select features geometrically equal to the reference geometry.

• dwithin(distance, units): Select features within a given distance of the reference geometry.

• beyond(distance, units): Select features farther than a given distance from the reference geometry.

• relate(pattern): Select features matching a DE-9IM spatial relationship pattern.

See Also

get_wfs()

Examples

intersects()
bbox()
dwithin(50, "meters")
beyond(100, "meters")
relate("T*F**F***")