

   FFoorrmmuullaa NNoottaattiioonn ffoorr SSccaatttteerrpplloott MMaattrriicceess

        pairs.formula(formula, data = NULL, subset, na.action, ...)

   AArrgguummeennttss::

    formula: a formula, such as `y ~ x'.

       data: a data.frame (or list) from which the variables in
             `formula' should be taken.

     subset: an optional vector specifying a subset of observa-
             tions to be used in the fitting process.

   na.action: a function which indicates what should happen
             when the data contain `NA's.

        ...: graphical parameters may also be passed as argu-
             ments, see `par'.

   DDeessccrriippttiioonn::

        Produce a matrix of scatterplots using formula nota-
        tion.

   DDeettaaiillss::

        This is a method of the generic function `pairs'.

   SSeeee AAllssoo::

        `pairs.default'

   EExxaammpplleess::

        data(swiss)
        pairs(~ Fertility + Education + Catholic,
              data = swiss, subset = Education < 20)

