[R] how to personalize split function in rpart

[Prof Brian Ripley]

Have you looked at the package sources? Do read rpart/tests/usersplits.R.

On Mon, 5 Jul 2004, Simone Vantini wrote:

> I am a student of the Politecnico di Milano (Milan, italy) and I'm working
> on CARTs. I'm trying to use the R rpart function with a personalized splitfunction... but I'm not able  to do it!
> More precisely, I would like to know what is the meaning of the function
> 'init', 'split' and 'eval' named in the help page.I can't find any answer
> in 'Classification and regression trees' (Breiman, ...) , in 'Modern
> applied statistics with S-plus' (Venables, Ripley) or even in the on-line
> forum.Thank You very much

Those are not about rpart.  See the S original at

	http://www.mayo.edu/hsr/Sfunc.html

for some further details (in rpart/Manuscript/AddMethods, about adding 
C-level split functions).

-- 
Brian D. Ripley,                  ripley at stats.ox.ac.uk
Professor of Applied Statistics,  http://www.stats.ox.ac.uk/~ripley/
University of Oxford,             Tel:  +44 1865 272861 (self)
1 South Parks Road,                     +44 1865 272866 (PA)
Oxford OX1 3TG, UK                Fax:  +44 1865 272595