plot.rpart {rpart}  R Documentation 
Plots an rpart object on the current graphics device.
## S3 method for class 'rpart': plot(x, uniform=FALSE, branch=1, compress=FALSE, nspace, margin=0, minbranch=.3, ...)
x 
a fitted object of class rpart , containing a classification,
regression, or rate tree.

uniform 
if TRUE , uniform vertical spacing of the nodes is used; this may be
less cluttered when fitting a large plot onto a page.
The default is to use a nonuniform spacing proportional to the
error in the fit.

branch 
controls the shape of the branches from parent to child node. Any number from 0 to 1 is allowed. A value of 1 gives square shouldered branches, a value of 0 give V shaped branches, with other values being intermediate. 
compress 
if FALSE , the leaf nodes will be at the horzontal plot coordinates of
1:nleaves .
If TRUE , the routine attempts a more compact arrangement of
the tree.
The compaction algorithm assumes uniform=TRUE ; surprisingly, the result
is usually an improvement even when that is not the case.

nspace 
the amount of extra space between a node with children and
a leaf, as compared to the minimal space between leaves.
Applies to compressed trees only. The default is the value of
branch .

margin 
an extra percentage of white space to leave around the borders of the tree. (Long labels sometimes get cut off by the default computation). 
minbranch 
set the minimum length for a branch to minbranch times the average
branch length. This parameter is ignored if uniform=TRUE .
Sometimes a split will give very little improvement, or even (in
the classification case) no improvement at all.
A tree with branch lengths strictly proportional to improvement
leaves no room to squeeze in node labels.

... 
arguments to be passed to or from other methods. 
This function is a method for the generic function plot
, for objects
of class rpart
.
The ycoordinate of the top node of the tree will always be 1.
the coordinates of the nodes are returned as a list, with
components x
and y
.
an unlabeled plot is produced on the current graphics device.
fit < rpart(Price ~ Mileage + Type + Country, cu.summary) plot(fit, compress=TRUE) text(fit, use.n=TRUE)