Tctext function

Easy way to add text labels to 'hclust' plot

Uses text() and Tcoords() to add text labels to 'hclust' plot

Tctext(hcl, labels=hcl[["labels"]], hang=0.1, add=0, horiz=FALSE, xpd=TRUE, ...)

Arguments

• hcl: hclust object
• labels: Character vector with the size of 'labels' component of 'hcl'; by default, these exact 'labels'
• hang: The fraction of the plot height by which labels should hang below the rest of the plot; by default, it is equal to the default 'hang' from hclust which is 0.1
• add: Add to 'hang' to make labels look better; the reliable value is about 0.03
• horiz: Plot on a horizontal tree?
• xpd: Plot text if it goes outside of the plotting region?
• ...: Further arguments to text()

Details

Please note that labels (similarly to Ploth()) are treated in their initial, pre-clustered order because Tctext() reorders everything internally. This is not similar to Tcoords() which treats them in order of their appearance on the dendrogram and therefore requires manual re-ordering.

Please feel free to use the simple enough code of this function to produce other convenient 'hclust'-labeling routines, for example, one can make 'Tcpoints' based on Tcoords() and points().

See Also

Tcoords, hclust, Ploth

Examples

hcl <- hclust(UScitiesD, "ward.D2")

## how to imitate the default plot.hclust() with Tctext()
old.par <- par(mfrow=c(1, 2))
plot(hcl, labels=gsub("[A-z.]", "  ", hcl$labels))
Tctext(hcl, srt=90, add=0.04, adj=c(1, 0.5))
plot(hcl)
par(old.par)

## how to use different properties of text()
plot(hcl, labels=FALSE)
Tctext(hcl, srt=45, add=0.02, adj=c(0.8, 1), font=2:1, col=1:5, cex=0.8)

## how to use Tctext() with Ploth()
old.par <- par(mar=c(3, 1, 0, 7))
Ploth(hcl, horiz=TRUE, labels=NA, col=c(1:5, 1:5), col.edges=TRUE)
Tctext(hcl, horiz=TRUE, hang=-1, col=1:5, pos=4, cex=1.1, font=3)
par(old.par)