TestRotation: utility function to test validity of rotation

In TreeHotspots: Hotspot Detection using Classification Trees

Description

utility function to test validity of rotation

Usage

TestRotation(x, angles = c(0, 30, 45, 60), center = c(0, 0), 


    OVERLAY = FALSE)

Arguments

x	data frame to be rotated
angles	angles to rotate over
center	center of rotation; another possible choice would be colMeans(x[,c("X","Y")])
OVERLAY	should the partition be overlaid graphically?

Author(s)

Markus Loecher

Examples

TestRotation()


 


TestRotation(center=c(2,2))


 


N= 250


x1 = cbind.data.frame(X=runif(N),Y=runif(N), violent = 0)


x2 = cbind.data.frame(X=runif(N),Y=runif(N,0.45,0.55), violent = 1)


x = rbind.data.frame(x1,x2)-c(0.5,0.5)


TestRotation(x, center=c(-0.5,-0.5))





cm=colMeans(x)


y1 = Rotate(x,a=0,center=cm)


y2 = Rotate(y1,a=0,center=cm,inverseRot=TRUE)


mean(abs(unlist(y2-x)))

TreeHotspots documentation built on May 2, 2019, 5:17 p.m.