Geometric binary predicates on pairs of simple feature geometry sets
st_intersects(x, y, sparse = TRUE, ...) st_disjoint(x, y = x, sparse = TRUE, prepared = TRUE) st_touches(x, y, sparse = TRUE, prepared = TRUE, ...) st_crosses(x, y, sparse = TRUE, prepared = TRUE, ...) st_within(x, y, sparse = TRUE, prepared = TRUE, ...) st_contains(x, y, sparse = TRUE, prepared = TRUE, ..., model = "open") st_contains_properly(x, y, sparse = TRUE, prepared = TRUE, ...) st_overlaps(x, y, sparse = TRUE, prepared = TRUE, ...) st_equals( x, y, sparse = TRUE, prepared = FALSE, ..., retain_unique = FALSE, remove_self = FALSE ) st_covers(x, y, sparse = TRUE, prepared = TRUE, ..., model = "closed") st_covered_by(x, y = x, sparse = TRUE, prepared = TRUE, ..., model = "closed") st_equals_exact(x, y, par, sparse = TRUE, prepared = FALSE, ...) st_is_within_distance(x, y = x, dist, sparse = TRUE, ...)
object of class
object of class
logical; should a sparse index list be returned (TRUE) or a dense logical matrix? See below.
passed on to s2_options
logical; prepare geometry for x, before looping over y? See Details.
character; polygon/polyline model; one of "open", "semi-open" or "closed"; see Details.
logical; if TRUE (and y is missing) return only indexes of points larger than the current index; this can be used to select unique geometries, see examples. This argument can be used for all geometry predictates; see als distinct.sf to find records where geometries AND attributes are distinct.
logical; if TRUE (and y is missing) return only indexes of geometries different from the current index; this can be used to omit self-intersections; see examples. This argument can be used for all geometry predictates
numeric; parameter used for "equals_exact" (margin);
distance threshold; geometry indexes with distances smaller or equal to this value are returned; numeric value or units value having distance units.
x contains POINT geometries and
y contains polygons, then the polygon geometries are prepared, rather than the points.
For most predicates, a spatial index is built on argument
x; see https://r-spatial.org/r/2017/06/22/spatial-index.html.
st_covered_by all build spatial indexes for more efficient geometry calculations.
st_equals_exact, and do not;
st_is_within_distance uses a spatial index for geographic coordinates when
sf_use_s2() is true.
y is missing, 'st_predicate(x, x)' is effectively called, and a square matrix is returned with diagonal elements 'st_predicate(x[i], x[i])'.
Sparse geometry binary predicate (
sgbp) lists have the following attributes:
region.id with the
x (if any, else
ncol with the number of features in
predicate with the name of the predicate used.
model, see https://github.com/r-spatial/s2/issues/32
‘st_contains_properly(A,B)' is true if A intersects B’s interior, but not its edges or exterior; A contains A, but A does not properly contain A.
See also st_relate and https://en.wikipedia.org/wiki/DE-9IM for a more detailed description of the underlying algorithms.
st_equals_exact returns true for two geometries of the same type and their vertices corresponding by index are equal up to a specified tolerance.
predicate e.g. "intersects") returns a dense logical matrix with element
predicate(x[i], y[j]) (e.g., when geometry of feature i and j intersect); if
sparse=TRUE, an object of class
sgbp with a sparse list representation of the same matrix, with list element
i an integer vector with all indices j for which
TRUE (and hence a zero-length integer vector if none of them is
TRUE). From the dense matrix, one can find out if one or more elements intersect by
apply(mat, 1, any), and from the sparse list by
lengths(lst) > 0, see examples below.
For intersection on pairs of simple feature geometries, use
st_intersection instead of
pts = st_sfc(st_point(c(.5,.5)), st_point(c(1.5, 1.5)), st_point(c(2.5, 2.5))) pol = st_polygon(list(rbind(c(0,0), c(2,0), c(2,2), c(0,2), c(0,0)))) (lst = st_intersects(pts, pol)) (mat = st_intersects(pts, pol, sparse = FALSE)) # which points fall inside a polygon? apply(mat, 1, any) lengths(lst) > 0 # which points fall inside the first polygon? st_intersects(pol, pts)[] # remove duplicate geometries: p1 = st_point(0:1) p2 = st_point(2:1) p = st_sf(a = letters[1:8], geom = st_sfc(p1, p1, p2, p1, p1, p2, p2, p1)) st_equals(p) st_equals(p, remove_self = TRUE) (u = st_equals(p, retain_unique = TRUE)) # retain the records with unique geometries: p[-unlist(u),]
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