Test a topological relationship

Each function compares x and y row by row and returns TRUE when the named DE-9IM relationship holds. y is recycled against x.

Usage

ga_contains(x, y)

ga_contains_properly(x, y)

ga_within(x, y)

ga_covers(x, y)

ga_covered_by(x, y)

ga_intersects(x, y)

ga_disjoint(x, y)

ga_touches(x, y)

ga_crosses(x, y)

ga_overlaps(x, y)

ga_equals_topo(x, y)

Arguments

x

a GeoArrow geometry array

y

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

Value

a boolean array of the same length as x

Details

ga_contains() is TRUE when no point of y lies outside x and at least one point of y lies in the interior of x. ga_within() is the same test with the arguments swapped. ga_covers() and ga_covered_by() are the weaker forms that allow every shared point to lie on the boundary. ga_contains_properly() is the stricter form requiring y to fall entirely within the interior.

ga_intersects() and ga_disjoint() are negations of one another. ga_touches() is TRUE when the geometries share a boundary point but no interior point, ga_crosses() when their interiors meet in a lower dimension than at least one of them, and ga_overlaps() when they meet in the same dimension as both. ga_equals_topo() compares point sets rather than coordinate order, so two geometries wound differently are still equal.

A null geometry on either side gives NA.

References

Relate

See also

Other topology: ga_coordinate_position(), ga_dimension(), ga_filter(), ga_is_empty(), ga_join(), ga_relate(), 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_contains(x, y))
#> [1] TRUE
as.vector(ga_intersects(x, y))
#> [1] TRUE