sf (version 0.5-2)

geos_binary_pred: Geometric binary predicates on pairs of simple feature geometry sets

Description

Geometric binary predicates on pairs of simple feature geometry sets

Usage

st_intersects(x, y, sparse = TRUE, prepared = 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)
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)
st_covers(x, y, sparse = TRUE, prepared = TRUE)
st_covered_by(x, y, sparse = TRUE, prepared = TRUE)
st_equals_exact(x, y, par, sparse = TRUE, prepared = FALSE)

Arguments

x

object of class sf, sfc or sfg

y

object of class sf, sfc or sfg

sparse

logical; should a sparse index list be returned (TRUE) or a dense logical matrix? See below.

prepared

logical; prepare geometry for x, before looping over y?

par

numeric; parameter used for "equals_exact" (margin);

Value

if sparse=TRUE, st_predicate (with predicate e.g. "intersects") returns a dense logical matrix with element i,j TRUE when predicate(x[i], y[j]) (e.g., when geometry i and j intersect); if sparse=FALSE, a sparse list representation of the same matrix, with list element i a numeric vector with the indices j for which predicate(x[i],y[j]) is TRUE (and hence integer(0) 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.

Details

for most predicates, a spatial index is built on argument x; see http://r-spatial.org/r/2017/06/22/spatial-index.html

`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.

Examples

# NOT RUN {
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)[[1]]
# }