

   FFiinndd tthhee rreessppoonnssee vveeccttoorr aanndd ddeessiiggnn mmaattrriixx ffoorr aa mmooddeell ffoorr--
   mmuullaa

        wr(formula)

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

    formula: A model formula.

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

        `wr' gives the response vector and design matrix for a
        formula in Wilkinson and Rogers notation.

   VVaalluuee::

        `wr' returns a list containing the response vector
        (z$response) and the design matrix (z$design) for the
        formula supplied.  e

   AAuutthhoorr((ss))::

        J.K. Lindsey

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

        y <- rnorm(20)
        x <- gl(4,5)
        z <- rpois(20,2)
        wr(y~x+z)

