

   PPlloottttiinngg ffaaccttoorr vvaarriiaabblleess

        plot.factor(x, y, legend.text = levels(y),...)

   AArrgguummeennttss::

        x,y: numeric or factor.  `y' may be missing.

   legend.text: a vector of text used to construct a legend for
             the plot. Only used if `y' is present and a fac-
             tor.

        ...: Further arguments to `plot', see also `par'.

   DDeessccrriippttiioonn::

        This functions implements a ``scatterplot'' method for
        `factor' arguments of the generic `plot' function.
        Actually, `boxplot' or `barplot' are used when appro-
        priate.

   SSeeee AAllssoo::

        `plot.default', `plot.formula', `barplot', `boxplot'.

   EExxaammpplleess::

        data(plants)
        plot(plants)                             # -> plot.data.frame
        plot(weight ~ group, data=plants)        # numeric vector ~ factor
        plot(cut(weight,2) ~ group, data=plants) # factor ~ factor

