library(tree)

data(cars)
cars.tr<-tree(dist~speed,data=cars)
print(cars.tr)
plot(cars.tr,type="u")
text(cars.tr)
# 理由不明だが、繰り返す必要あり
plot(cars.tr,type="u")
text(cars.tr)


(cars.tr1<-prune.tree(cars.tr,best=4))
plot(cars.tr1); text(cars.tr1,all=T)

plot(cars$speed,cars$dist)
partition.tree(cars.tr1,add=T,col=2)


data(iris)

(iris.tr<-tree(Species~.,data=iris))
plot(iris.tr,type="u"); text(iris.tr)

(iris.tr1<-snip.tree(iris.tr,nodes=c(12,7)))
plot(iris.tr1,type="u");text(iris.tr1)


iris.label<-c("S", "C", "V")[iris[, 5]]
plot(iris[,3],iris[,4],type="n")
text(iris[,3],iris[,4],labels=iris.label)
partition.tree(iris.tr1,add=T,col=2,cex=1.5)

iris.color<-c("red","blue","green")[iris[,5]]
plot(iris[,3],iris[,4],col=iris.color)
partition.tree(iris.tr1,add=T,col=2,cex=1.5)