R devel - May 2006 - row.names != rownames for data.frame?

With a recent R 2.4 I notice the following:

df <- data.frame(x=1:2)
> row.names(df)
[1] "1" "2"
> rownames(df)
[1] 1 2

This seems related to recent changes in the internal storage format of
the row names data for data frames. 

The man page for rownames says:

     For a data frame, 'rownames' and 'colnames' are equivalent
to
     'row.names' and 'names' respectively.

A number of Bioconductor packages seem to be relying on this.


--

+ seth




R.version
               _                                                               
platform       powerpc-apple-darwin8.6.0                                       
arch           powerpc                                                         
os             darwin8.6.0                                                     
system         powerpc, darwin8.6.0                                            
status         Under development (unstable)                                    
major          2                                                               
minor          4.0                                                             
year           2006                                                            
month          05                                                              
day            01                                                              
svn rev        37951                                                           
language       R                                                               
version.string R version 2.4.0 Under development (unstable) (2006-05-01 r37951)

On Mon, 1 May 2006, Seth Falcon wrote:
> With a recent R 2.4 I notice the following:
>
> df <- data.frame(x=1:2)
>> row.names(df)
> [1] "1" "2"
>> rownames(df)
> [1] 1 2
>
> This seems related to recent changes in the internal storage format of
> the row names data for data frames.
>
> The man page for rownames says:
>
>     For a data frame, 'rownames' and 'colnames' are
equivalent to
>     'row.names' and 'names' respectively.
>
> A number of Bioconductor packages seem to be relying on this.
Interesting: nothing on CRAN did.  Those are `equivalent' but not 
identical, but let's make them identical again.


-- 
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