Place Text on a Dendrogram

Labels the current plot of the tree dendrogram with text.

Usage

# S3 method for class 'rpart'
text(x, splits = TRUE, which = 4, label = "yval", FUN = text, 
    all.leaves = FALSE, pretty = NULL, digits = getOption("digits") - 2,
    tadj = 0.65, stats = TRUE, use.n = FALSE, bars = TRUE, 
    legend = FALSE, xadj = 1, yadj = 1, bord = FALSE, big.pts = FALSE,
    uniform = FALSE, branch = 1, nspace = -1, minbranch = 0.3, ...)

Arguments

x

fitted model object of class rpart. This is assumed to be the result of some function that produces an object with the same named components as that returned by the rpart function.

splits

logical flag. If TRUE (default), then the splits in the tree are labeled with the criterion for the split.

which

labels splits 1 = center, 2 = left, 3 = right , 4 = both.

label

a column name of x$frame; values of this will label the nodes. For the "class" method, label="yval" results in the factor levels being used, "yprob" results in the probability of the winning factor level being used, and 'specific yval level' results in the probability of that factor level.

FUN

the name of a labeling function, e.g. text.

all.leaves

Logical. If TRUE, all nodes are labeled, otherwise just terminal nodes.

tadj

Adjustment of text above (or below) splits.

pretty

an integer denoting the extent to which factor levels in split labels will be abbreviated. A value of (0) signifies no abbreviation. A NULL, the default, signifies using elements of letters to represent the different factor levels.

digits

number of significant digits to include in numerical labels.

stats

If TRUE adds statistics to nodes.

use.n

If TRUE adds N to labels. (\#events level1/ \#events level2/etc. for class, n for anova, and \#events/n for poisson and exp).

bars

If TRUE adds barplots for multivariate regression trees.

legend

If TRUE adds legends for multivariate regression trees.

xadj, yadj

varies the size of barplots for multivariate regression trees.

bord

Adds borders (boxes) to barplots for multivariate regression trees.

big.pts

Adds color coded points to nodes. Useful to track groups to PCA plot (see rpart.pca).

uniform

Uniform spacing of tree branches; defualt is FALSE.

branch

branch parameter default = 1.

nspace

branch parameter default = 1.

minbranch

minimum branch parameter default = 0.3.

...

Graphical parameters may also be supplied as arguments to this function (see par).

Side Effects

the current plot of a tree dendrogram is labeled.

See also

text, plot.rpart, rpart, post.rpart, abbreviate

Examples

data(car.test.frame)
z.auto <- rpart(Mileage ~ Weight, car.test.frame)
plot(z.auto)
text(z.auto, use.n=TRUE, all=TRUE)