balancedGrouped             package:nlme             R Documentation

_C_r_e_a_t_e _a _g_r_o_u_p_e_d_D_a_t_a _o_b_j_e_c_t _f_r_o_m _a _m_a_t_r_i_x

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

     Create a `groupedData' object from a data matrix.  This function
     can be used only with balanced data.  The opposite conversion,
     from a `groupedData' object to a `matrix', is done with `asTable'.

_U_s_a_g_e:

     balancedGrouped(form, data, labels=NULL, units=NULL)

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

    form: A formula of the form `y ~ x | g' giving the name of the
          response, the primary covariate, and the grouping factor.

    data: A matrix or data frame containing the values of the response
          grouped according to the levels of the grouping factor (rows)
          and the distinct levels of the primary covariate (columns).
          The `dimnames' of the matrix are used to construct the levels
          of the grouping factor and the primary covariate.

  labels: an optional list of character strings giving labels for the
          response and the primary covariate.  The label for the
          primary covariate is named `x' and that for the response is
          named `y'.  Either label can be omitted.

   units: an optional list of character strings giving the units for
          the response and the primary covariate.  The units string for
          the primary covariate is named `x' and that for the response
          is named `y'.  Either units string can be omitted.

_V_a_l_u_e:

     A balanced `groupedData' object.

_A_u_t_h_o_r(_s):

     Jose Pinheiro and Douglas Bates

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

     `groupedData', `isBalanced', `asTable'

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

     data(Orthodont)
     OrthoMat <- asTable( Orthodont )
     Orth2 <- balancedGrouped(distance ~ age | Subject, data = OrthoMat,
         labels = list(x = "Age",
                       y = "Distance from pituitary to pterygomaxillary fissure"),
         units = list(x = "(yr)", y = "(mm)"))
     Orth2[ 1:10, ]        ## check the first few entries

