R/displayLegend.R

In HMPTrees: Statistical Object Oriented Data Analysis of RDP-Based Taxonomic Trees from Human Microbiome Data

displayLegend <-
function(colors=NULL, divisions=NULL, title="Confidence Value"){
	### Default tree branch splits
	if(is.null(divisions)) 
		divisions <- c(0, .1, 1, 10, 100, 1000, 10000)
	divisions <- sort(divisions)
	
	### Default tree branch colors
	if(is.null(colors)) 
		colors <- c("red", "orange", "yellow", "green" , "cyan", "blue")
	
	if(length(divisions) > (length(colors)+1)) # need more colors, dont care if more colors than divisons
		colors <- c(colors, rep(colors[length(colors)], (length(divisions) - length(colors)-1)))
	
	### Get the legend wording
	lgd <- NULL
	for(num in length(divisions):2)
		lgd <- c(lgd, paste(divisions[num], "-", divisions[num-1], sep=""))
	
	### Plot the legend on a new page
	grDevices::palette(colors)
	plot(0, 0, type="n", xlab="", ylab="", xaxt="n", yaxt="n", bty="n")
	legend(-.75, .75, legend=lgd, col=rev(palette()), pch=19, title=title)
}