[R] Indexing column of a matrix with infix $

[Gabor Grothendieck]

as.data.frame(matrixname)$validname

chris1 <chris1 <at> psyctc.org> writes:

: 
: I'm using 1.9.0 on Windoze 2k and I created a numeric matrix and used
: colnames() to give it some column names, but if I try to select a
: column using matrixname$validname I get a null return but if I use
: matrixname[,4] it works fine.  Looking at the help I think this is
: because a matrix is not a recursive structure and I think it's saying
: I shouldn't be surprised nor attempt this.
: 
: I'm in the process of transferring all my stats work to R having used
: a mixture of SPSS, S and SAS (and snippets of other things) over the
: years so sorry if I'm being dumb but this surprised me and I'd love a
: kindly explanation as I thought indexing a matrix in this way was
: something I did regularly (I think the last time was actually using it
: on a dataframe though) and I also think it would be useful and produce
: more readable code if I could.
: 
: Can some kindly soul explain?
: 
: TIA,
: 
: Chris
: 
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