[R] how to get the numbers of factors in a matrix

[peter dalgaard]

On 21 Jan 2014, at 15:58 , Jeff Newmiller <jdnewmil at dcn.davis.ca.us> wrote:

> You are mis-using factors. Would you pretend that women do not exist just because your sample happens to include only men?
> 
> If you really need to ignore those other levels, convert your factor to character and summarize those values.

Actually, just factor(fff) will do. Or droplevels(fff).


-- 
Peter Dalgaard, Professor
Center for Statistics, Copenhagen Business School
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