

   GGeenneerraalliizzeedd NNoonnlliinneeaarr LLeeaasstt SSqquuaarreess SSttrruuccttuurree

        gnlsStruct(corStruct, varStruct)

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

   corStruct: an optional `corStruct' object, representing a
             correlation structure. Default is `NULL'.

   varStruct: an optional `varFunc' object, representing a
             variance function structure. Default is `NULL'.

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

        A generalized nonlinear least squares structure is a
        list of model components representing different sets of
        parameters in the nonlinear model. A `gnlsStruct'  may
        contain `corStruct' and `varFunc' objects. `NULL' argu-
        ments are not included in the `gnlsStruct' list.

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

        a list of model variance-covariance components deter-
        mining the parameters to be estimated for the associ-
        ated nonlinear model.

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

        Jose Pinheiro and Douglas Bates

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

        `gnls', `corClasses', `varFunc'

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

        library(lme)
        gnls1 <- gnlsStruct(corAR1(), varPower())

