[R] convert factor dataframe into numeric matrix

[Prof Brian Ripley]

On Wed, 24 Oct 2007, sun wrote:

> Bear me if this is a naive question.
>
> I have a dataframe, all lists inside it are factors. When I use

Do you mean 'all columns are factors'?  A data frame is a list but usually 
does not contain lists.

> as.matrix(df) to convert, I get a character matrix while my intention is to
> get numeric matrix. I can make the convertion  iteratively by each list but
> I do think there is some more elegant way of doing this.
>
> please let me know if I missed somthing there.

?data.matrix  may be what you are looking for: you gave us too little 
detail to be sure.

-- 
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