

   EExxttrraacctt VVaarriiaannccee FFuunnccttiioonn WWeeiigghhttss

        varWeights(object)

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

     object: an object inheriting from class code{varFunc},
             representing a variance function structure.

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

        The inverse of the standard deviations corresponding to
        the variance function structure represented by `object'
        are returned.

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

        if `object' has a `weights' attribute, its value is
        returned; else `NULL' is returned.

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

        Jose Pinheiro and Douglas Bates

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

        `logLik.varFunc'

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

        library(lme)
        data(Orthodont)
        vf1 <- varPower(form=~age)
        vf1 <- initialize(vf1, Orthodont)
        coef(vf1) <- 0.3
        varWeights(vf1)[1:10]

