[R] How to collect trees grown by rpart

[Jonathan Williams]

I would like to collect the trees grown by rpart fits in an array,
in order to be able to use them later to predict new data. I have 
tried to use parse and eval to do this, without success. I'd be 
very grateful if someone could explain how to do it.

The kind of thing I hope to do is:

resmat=array(NA, 100)
for (run in 1:100) resmat[run]=rpart(y~., data=train[run])

So that, later, I can do:
for (run in 1:100) pred[run]=predict(resmat[run], newdat)

But, resmat[run] does not work, even though it saves the cptables. 

Thanks, in advance,

Jonathan Williams
OPTIMA
Radcliffe Infirmary
Woodstock Road
OXFORD OX2 6HE
Tel +1865 (2)24356