spatial.select: Spatial Select

In spatialEco: Spatial Analysis and Modelling Utilities

Spatial Select

Description

Performs a spatial select (feature subset) between a polygon(s) and other feature class

Usage

spatial.select(
  x,
  y = NULL,
  distance = NULL,
  predicate = c("intersection", "intersect", "contains", "covers", "touches",
    "proximity", "contingency"),
  neighbors = c("queen", "rook")
)

Arguments

x	An sp or sf polygon(s) object that defines the spatial query
y	A sp or sf feature class that will be subset by the query of x
distance	A proximity distance of features to select (within distance)
predicate	Spatial predicate for intersection
neighbors	If predicate = "contingency" type of neighbors options are c("queen", "rook")

Details

Performs a spatial select of features based on an overlay of a polygon (x), which can represent multiple features, and a polygon, point or line feature classes (y). User can specify a partial or complete intersection, using within argument, or within a distance, using distance argument, predicated on the query polygon. This function is similar to ArcGIS/Pro spatial select. Please note that for point to point neighbor selections use the knn function. Valid spatial predicates include: intersect, touches, covers, contains, proximity and contingency. See DE-9IM topology model for detailed information on following data predicates.

• intersection Create a spatial intersection between two features

• intersect Boolean evaluation of features intersecting

• contains Boolean evaluation of x containing y

• covers Boolean evaluation of x covering y

• touches Boolean evaluation of x touching y

• proximity Evaluation of distance-based proximity of x to y (x and y can be the same)

• contingency Evaluation of polygon contingency (eg., 1st, 2nd order)

Value

An sf object representing a subset of y based on the spatial query of x or, if predicate = contingency a sparse matrix representing neighbor indexes

Author(s)

Jeffrey S. Evans [e-mail]

See Also

st_intersection for details on intersection predicate

st_intersects for details on intersect predicate

st_contains for details on contain predicate

st_covers for details on covers predicate

st_touches for details on touches predicate

st_is_within_distance for details on proximity predicate

https://en.wikipedia.org/wiki/DE-9IM for details on DE-9IM topology model

Examples

if(require(sp, quietly = TRUE)) {
library(sf)
  data(meuse, package = "sp")
  meuse <- st_as_sf(meuse, coords = c("x", "y"), crs = 28992, 
                    agr = "constant")

spolys <- hexagons(meuse, res=100)
  spolys$ID <- 1:nrow(spolys)
    p <- st_as_sf(st_sample(spolys, 500))
	  p$PTID <- 1:nrow(p) 
	  sf::st_geometry(p) <- "geometry"

  plot(st_geometry(spolys), main="all data")
    plot(st_geometry(p), pch=20, add=TRUE)
	
sub.int <- spatial.select(p, spolys, predicate = "intersect")
  plot(st_geometry(sub.int), main="intersects")
    plot(st_geometry(p), pch=20, add=TRUE)	

sub.prox <- spatial.select(p, spolys, distance=100, predicate = "proximity")	
  plot(st_geometry(sub.int), main="intersects")
    plot(st_geometry(p), pch=20, add=TRUE)

# For rook or queen polygon contingency 	
plot( spolys <- sf::st_make_grid(sf::st_sfc(sf::st_point(c(0,0)), 
                 sf::st_point(c(3,3))), n = c(3,3)) )
  
spatial.select(x=spolys, predicate = "contingency")
spatial.select(spolys, predicate = "contingency", neighbors = "rook") 

} else { 
  cat("Please install sp package to run example", "\n")
}

spatialEco documentation built on Nov. 18, 2023, 1:13 a.m.