R/post.itree.R

In itree: Tools for classification and regression trees, with an emphasis on interpretability.

#ALG: itree copies this direclty from rpart.

# SCCS 05/11/01 @(#)post.rpart.s	1.13
#
post.itree <- function(tree, title.,
		       filename=paste(deparse(substitute(tree)),".ps",sep=""),
		       digits=getOption("digits") - 3, pretty=TRUE,
		       use.n=TRUE,  horizontal=TRUE, ...)
{
    if(filename !=""){
	postscript(file = filename, horizontal=horizontal, ...)
	par(mar=c(2,2,4,2)+.1)
	on.exit(dev.off())
	}
    else {
	oldpar <- par(mar=c(2,2,4,2)+.1)
	on.exit(invisible(par(oldpar)))
	}

    plot(tree, uniform=TRUE, branch=.2, compress=TRUE, margin=.1)
    text(tree, all=TRUE, use.n=use.n, fancy=TRUE, digits=digits, pretty=pretty)

    if(missing(title.)) {
        temp  <- attr(tree$terms,'variables')[2L]
        title(paste("Endpoint =",temp),cex=.8)
    } else if (title. !="") title(title.,cex=.8)
}