R/in.W.poly.R

In baddstats/spherstat: Spatial Point Pattern Analysis, Geometry and Trigonometry for the Sphere

in.W.poly <- function(points, win=sphwin(type="sphere")) {
	stopifnot(inherits(points, c("sp2", "sp3", "matrix")))
	if(inherits(points, "matrix")) {
		stopifnot(inherits(win, "sphwin"))
	}
	else {
		win <- points$win
		points <- points$X
		stopifnot(inherits(win, "sphwin"))
	}
	rad <- win$rad
	n <- nrow(points)
	lp <- nrow(win$param)
	p3 <- convert3(win$param)

	if(ncol(points) !=3) {
		points <- convert3(points)
	}
	polyangs1 <- p3[1:(lp-1),]
	polyangs2 <- p3[2:lp,]
	polyangs3 <- rbind(p3[3:lp, ], p3[2,])
	gc <- gcdistPaired(x=polyangs1, y=polyangs2, rad=rad)
	gc1 <- gc[1:(lp-1)]
	gc2 <- c(gc[2:(lp-1)], gc[1])
	sphang <- sph.angles(win)
	gc.pv1 <- gcdist(x=points, y=polyangs1)
	gc.pv2 <- gcdist(x=points, y=polyangs2)
	gc.pv3 <- gcdist(x=points, y=polyangs3)
			sc1 <- sphcos(d1=gc1, d2=gc.pv2, d3=gc.pv1, theta=NULL, rad=rad)
			sc2 <- sphcos(d1=gc2, d2=gc.pv2, d3=gc.pv3, theta=NULL, rad=rad)
	test <- abs(sc1+sc2-matrix(rep(sphang, n), nrow=n, ncol=lp-1, byrow=TRUE))
	test <- ifelse(is.na(test), 0, test)
	test1 <- rowSums(sround(test)<10^-7)
	isinW <- test1==lp-1
	isinW
}