R help - Feb 2005 - How to write a new "top-level" Trellis/lattice function?

Hello,

I am trying to write a new "top level" Trellis/lattice function.
By "top-level", I mean a function like 'xyplot',
'histogram',
'bwplot', etc.
These functions all call 'trellis.skeleton', which I am unable to
call;
an attempt to invoke the function that does so yields the error
message:

-----
Error in do.call("trellis.skeleton", c(list(cond = cond, aspect
aspect,  :
        couldn't find function "trellis.skeleton"
-----

It seems that 'trellis.skeleton' is an internal (to lattice) function.
Is this correct, and if so, what is the recommended way to develop a
new
top-level Trellis/lattice function?

best regards,
Marc

----
Dr. Marc Paterno
Fermi National Accelerator Laboratory

you can see the trellis.skeleton function using the following:

library(lattice)
getAnywhere(trellis.skeleton)
f <- getAnywhere(trellis.skeleton)[[2]][[1]]

I hope it helps.

Best,
Dimitris

----
Dimitris Rizopoulos
Ph.D. Student
Biostatistical Centre
School of Public Health
Catholic University of Leuven

Address: Kapucijnenvoer 35, Leuven, Belgium
Tel: +32/16/336899
Fax: +32/16/337015
Web: http://www.med.kuleuven.ac.be/biostat
     http://www.student.kuleuven.ac.be/~m0390867/dimitris.htm


----- Original Message ----- 
From: "Marc Paterno" <paterno at fnal.gov>
To: <r-help at stat.math.ethz.ch>
Sent: Tuesday, February 01, 2005 2:53 PM
Subject: [R] How to write a new "top-level" Trellis/lattice function?

> Hello,
>
> I am trying to write a new "top level" Trellis/lattice function.
> By "top-level", I mean a function like 'xyplot',
'histogram',
> 'bwplot', etc.
> These functions all call 'trellis.skeleton', which I am unable to
> call;
> an attempt to invoke the function that does so yields the error
> message:
>
> -----
> Error in do.call("trellis.skeleton", c(list(cond = cond, aspect
> aspect,  :
>        couldn't find function "trellis.skeleton"
> -----
>
> It seems that 'trellis.skeleton' is an internal (to lattice) 
> function.
> Is this correct, and if so, what is the recommended way to develop a
> new
> top-level Trellis/lattice function?
>
> best regards,
> Marc
>
> ----
> Dr. Marc Paterno
> Fermi National Accelerator Laboratory
>
> ______________________________________________
> R-help at stat.math.ethz.ch mailing list
> https://stat.ethz.ch/mailman/listinfo/r-help
> PLEASE do read the posting guide! 
> http://www.R-project.org/posting-guide.html
>

On Tuesday 01 February 2005 07:53, Marc Paterno wrote:
> Hello,
>
> I am trying to write a new "top level" Trellis/lattice function.
> By "top-level", I mean a function like 'xyplot',
'histogram',
> 'bwplot', etc.
> These functions all call 'trellis.skeleton', which I am unable to
> call;
> an attempt to invoke the function that does so yields the error
> message:
>
> -----
> Error in do.call("trellis.skeleton", c(list(cond = cond, aspect
> aspect,  :
>         couldn't find function "trellis.skeleton"
> -----
> 
> It seems that 'trellis.skeleton' is an internal (to lattice)
> function. Is this correct, and if so, what is the recommended way to
> develop a new
> top-level Trellis/lattice function?
What do you need to do that cannot be done by writing special panel and 
prepanel functions? See for example, the definition of dotplot, or 
xYplot in package Hmisc.

The only reason to have a new top-level function I can think of is if 
you need a fundametally different form of the formula. If that's the 
case, can you give us more details?

Deepayan