https://github.com/cran/spatstat
Tip revision: e05bea54a1749f83bcd9edf839f818fd6276b9d1 authored by Adrian Baddeley on 11 June 2012, 08:51:22 UTC
version 1.28-0
version 1.28-0
Tip revision: e05bea5
is.subset.owin.R
#
# is.subset.owin.R
#
# $Revision: 1.8 $ $Date: 2012/05/09 00:32:56 $
#
# Determine whether a window is a subset of another window
#
# is.subset.owin()
#
is.subset.owin <- local({
is.subset.owin <- function(A, B) {
A <- as.owin(A)
B <- as.owin(B)
if(identical(A, B))
return(TRUE)
A <- rescue.rectangle(A)
B <- rescue.rectangle(B)
if(is.rectangle(B)) {
# Some cases can be resolved using convexity of B
# (1) A is also a rectangle
if(is.rectangle(A)) {
xx <- A$xrange[c(1,2,2,1)]
yy <- A$yrange[c(1,1,2,2)]
ok <- inside.owin(xx, yy, B)
return(all(ok))
}
# (2) A is polygonal
# Then A is a subset of B iff,
# for every constituent polygon of A with positive sign,
# the vertices are all in B
if(is.polygonal(A)) {
ok <- unlist(lapply(A$bdry, okpolygon, B=B))
return(all(ok))
}
# (3) Feeling lucky
# Test whether the bounding box of A is a subset of B
# Then a fortiori, A is a subset of B
AA <- bounding.box(A)
if(is.subset.owin(AA, B))
return(TRUE)
}
if(!is.mask(A) && !is.mask(B)) {
# rectangles or polygonal domains
if(!all(inside.owin(vertices(A), , B)))
return(FALSE)
# all vertices of A are inside B.
if(is.convex(B))
return(TRUE)
# compare area of intersection with area of A
return(overlap.owin(A,B) >= area.owin(A))
}
# Discretise
a <- as.mask(A)
b <- as.mask(B)
xx <- as.vector(raster.x(a)[a$m])
yy <- as.vector(raster.y(a)[a$m])
ok <- inside.owin(xx, yy, b)
return(all(ok))
}
okpolygon <- function(a, B) {
if(area.xypolygon(a) < 0) return(TRUE)
ok <- inside.owin(a$x, a$y, B)
return(all(ok))
}
is.subset.owin
})