fitted model object of class
tree.
This is assumed to be the result of some function that produces
an object with the same named
components as that returned by the
tree function.
x
matrix of predictors.
VALUE:
a vector of integers giving the row number of
tree$frame of
the terminal node that each observation referenced in
x falls into.
This function is called by
predict.tree and not directly by users.
In particular,
pred.tree does not check to see if the predictors
in
x match those used to grow
tree.