tree: Plot Trees

Description

This function makes a graphical diagram of multivariate data. Every element represents one branch of the tree and the length of the branch indicates the concentration of the element.

Usage

tree(x, wmax = 0, wmin = 0, lh = 1, labels = dimnames(x)[[1]], locations = NULL,
nrow = NULL, ncol = NULL, key.loc = NULL, key.labels = dimnames(x)[[2]],
key.xpd = TRUE, xlim = NULL, ylim = NULL, flip.labels = NULL, len = 1,
leglen = 1, leglh = 1, axes = FALSE, frame.plot = axes, main = NULL, sub = NULL,
xlab = "", ylab = "", cex = 0.8, lwd = 0.25, lty = par("lty"), xpd = FALSE,
mar = pmin(par("mar"), 1.1 + c(2 * axes + (xlab != ""), 2 * axes + (ylab != ""),
 1, 0)), add = FALSE, plot = TRUE, ...)

Arguments

multivariate data in form of matrix or data frame

wmax, wmin

maximum and minimum angle for the leaves of the tree

multiplier for height

labels

vector of character strings for labeling the plots

locations

locations for the boxes on the plot (e.g. X/Y coordinates)

nrow, ncol

integers giving the numbers of rows and columns to use when location=NULL. By default, 'nrow==ncol', a square layout will be used.

key.loc

vector with x and y coordinates of the unit key.

key.labels

vector of character strings for labeling the segments of the unit key. If omitted, the second component of 'dimnames(x)' is used, if available.

key.xpd

clipping switch for the unit key (drawing and labeling), see 'par("xpd")'

xlim

vector with the range of x coordinates to plot

ylim

vector with the range of y coordinates to plot

flip.labels

logical indication if the label locations should flip up and down from diagram to diagram. Defaults to a somewhat smart heuristic.

len, leglen, leglh

multiplicative values for the space of the labels on the legend

axes

logical, if TRUE axes are added to the plot

frame.plot

if TRUE the plot region is framed

main

a main title for the plot

sub

a sub title for the plot

xlab

a label for the x-axis

ylab

a label for the y-axis

cex

character expansion factor for the labels

lwd

line width used for drawing

lty

line type used for drawing

xpd

logical or NA indicating if clipping should be done, see 'par(mar=*)'

mar

argument to 'par(mar=*)', typically choosing smaller margins than by default.

add

if TRUE add boxes to current plot

plot

if FALSE nothing is plotted

...

further arguments, passed to the first call of 'plot()', see 'plot.default'

Details

Each tree represents one row of the input x. Each branch of the tree represents one choosen element and the length of the branches shows the value of the variable. The different concentrations of each row in x is displayed by the shape of the tree.

References

C. Reimann, P. Filzmoser, R.G. Garrett, and R. Dutter: Statistical Data Analysis Explained. Applied Environmental Statistics with R. John Wiley and Sons, Chichester, 2008.

Examples

Run this code

data(ohorizon)
X=ohorizon[,"XCOO"]
Y=ohorizon[,"YCOO"]
el=log10(ohorizon[,c("Co","Cu","Ni","Rb","Bi","Na","Sr")])
sel <- c(3,8,22, 29, 32, 35, 43, 69, 73 ,93,109,129,130,134,168,181,183,205,211,
      218,237,242,276,292,297,298,345,346,352,372,373,386,408,419,427,441,446,490,
      516,535,551,556,558,564,577,584,601,612,617)
x=el[sel,]

tree(x,key.loc=c(15,0),len=0.022, lh=30,leglh=4,
    wmax=120,wmin=30, leglen=0.05, ncol=8, cex=0.75)