DE-9IM relationship between geometries

Returns the nine character DE-9IM matrix describing how each pair of geometries relates, from which every named predicate can be derived.

Usage

ga_relate(x, y)

Arguments

x

a GeoArrow geometry array

y

a GeoArrow geometry array; length 1 or the same length as x

Value

a string array of the same length as x

Details

The string reads as the intersections of the interior, boundary and exterior of x with those of y, in that order. Each character is the dimension of that intersection: F for empty, 0 for a point, 1 for a curve, and 2 for a surface. A null geometry on either side gives NA.

References

Relate

See also

Other topology: ga_contains(), ga_coordinate_position(), ga_dimension(), ga_filter(), ga_is_empty(), ga_join(), ga_sparse_intersects(), ga_sparse_pairs()

Examples

big <- sf::st_polygon(list(
  matrix(c(0, 0, 4, 0, 4, 4, 0, 4, 0, 0), ncol = 2, byrow = TRUE)
))
x <- geoarrow::as_geoarrow_array(sf::st_sfc(big))
y <- geoarrow::as_geoarrow_array(sf::st_sfc(sf::st_point(c(2, 2))))

as.vector(ga_relate(x, y))
#> [1] "0F2FF1FF2"