Dim.corStruct              package:nlme              R Documentation

_D_i_m_e_n_s_i_o_n_s _o_f _a _c_o_r_S_t_r_u_c_t _O_b_j_e_c_t

_D_e_s_c_r_i_p_t_i_o_n:

     if 'groups' is missing, it returns the 'Dim' attribute of
     'object'; otherwise, calculates the dimensions associated with the
     grouping factor.

_U_s_a_g_e:

     ## S3 method for class 'corStruct':
     Dim(object, groups, ...)

_A_r_g_u_m_e_n_t_s:

  object: an object inheriting from class 'corStruct', representing a
          correlation structure.

  groups: an optional factor defining the grouping of the observations;
          observations within a group are correlated and observations
          in different groups are uncorrelated.

     ...: some methods for this generic require additional arguments. 
          None are used in this method.

_V_a_l_u_e:

     a list with components: 

       N: length of 'groups'

       M: number of groups

  maxLen: maximum number of observations in a group

sumLenSq: sum of the squares of the number of observations per group

     len: an integer vector with the number of observations per group

   start: an integer vector with the starting position for the
          observations in each group, beginning from zero

_A_u_t_h_o_r(_s):

     Jose Pinheiro Jose.Pinheiro@pharma.novartis.com and Douglas Bates
     bates@stat.wisc.edu

_S_e_e _A_l_s_o:

     'Dim', 'Dim.corSpatial'

_E_x_a_m_p_l_e_s:

     data(Orthodont)
     Dim(corAR1(), getGroups(Orthodont))

