R help - May 2007 - Writing custom functions for rpart

Hi everyone,

Does anyone has experience with (or documentation for) writing custom
methods with rpart? The documentation hints: "Alternatively,
'method'
can be a list of functions 'init', 'split' and
'eval'", but doesn't
provide any details as to what those methods should do or what
arguments they should take etc.

I've tried looking at the package source (and the source for the S
code it came from) but I can't follow what's going on in C vs R, and
as the default methods are coded in a different way, there are no
examples to follow.

Thanks,

Hadley

On Wed, 9 May 2007, hadley wickham wrote:
> Hi everyone,
>
> Does anyone has experience with (or documentation for) writing custom
> methods with rpart? The documentation hints: "Alternatively,
'method'
> can be a list of functions 'init', 'split' and
'eval'", but doesn't
> provide any details as to what those methods should do or what
> arguments they should take etc.
>
> I've tried looking at the package source (and the source for the S
> code it came from) but I can't follow what's going on in C vs R,
and
> as the default methods are coded in a different way, there are no
> examples to follow.
But there are, in the tests directory.

-- 
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)
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