

getGroups(nlme)                              R Documentation

_E_x_t_r_a_c_t _G_r_o_u_p_i_n_g _F_a_c_t_o_r_s _f_r_o_m _a_n _O_b_j_e_c_t

_D_e_s_c_r_i_p_t_i_o_n_:

     This function is generic; method functions can be writ-
     ten to handle specific classes of objects. Classes
     which already have methods for this function include
     `corStruct', `data.frame', `gls', `lme', `lmList', and
     `varFunc'.

_U_s_a_g_e_:

     getGroups(object, form, level, data)

_A_r_g_u_m_e_n_t_s_:

  object: any object

    form: an optional formula with a conditioning expression
          on its right hand side (i.e. an expression involv-
          ing the `|' operator). Defaults to `for-
          mula(object)'.

   level: a positive integer vector with the level(s) of
          grouping to be used when multiple nested levels of
          grouping are present. This argument is optional
          for most methods of this generic function and
          defaults to all levels of nesting.

    data: a data frame in which to interpret the variables
          named in `form'. Optional for most methods.

_V_a_l_u_e_:

     will depend on the method function used; see the appro-
     priate documentation.

_A_u_t_h_o_r_(_s_)_:

     Jose Pinheiro and Douglas Bates

_S_e_e _A_l_s_o_:

     `getGroupsFormula', `getGroups.data.frame', `get-
     Groups.gls', `getGroups.lmList', `getGroups.lme'

_E_x_a_m_p_l_e_s_:

     ## see the method function documentation

