SubscriptList         package:externalVector         R Documentation

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_o_f _c_l_a_s_s _v_e_c_t_o_r_I_n_d_e_x.

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

     SubscriptList takes a list of subscripts to a subset or subassign
     operation and converts each subscript to an object belonging to
     the virtual class 'vectorIndex'.

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

     SubscriptList(subs, length.object, dim.object = NULL, names.object = NULL, dimnames.object = NULL, assign.operation = FALSE)

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

    subs: An object of class "list", elements are valid subscripts. 

length.object: A scalar of class "integer", representing the length of
          the object being subsetted or subassigned. 

dim.object: An object of class "integer" or 'NULL', the dimension of
          the object. 

names.object: An object belonging to class union "validNamesClass", the
          names of the object viewed as a vector. 

dimnames.object: 'NULL' or an object of class "list", each of whose
          elements are objects belonging to class union
          "validNamesClass". 

assign.operation: A scalar of class "logical", if 'TRUE' the subscripts
          are for a subasign operation, if 'FALSE', the subscripts are
          for a subset operation. 

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

     An object of class "list" of same length as 'subs' with each
     element a

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

     Saikat DebRoy <saikat@stat.wisc.edu>

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

     See class union 'vectorNamesType-class' for possible subscripts
     which are matched against the 'names.object' or elements of
     'dimnames.object'.

     Also see class union 'vectorIndex-class' for some other possible
     subscripts and for all possible elements in the returned list.

     Finally, see '[' for other subscripts that are valid.

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

     subs <- alist(i= , j= )
     subs$j <- 1:4
     SubscriptList(subs, 15, c(3, 5))
     SubscriptList(list(i=c("a", "c"), j=-2), 15, c(3, 5),
                   dimnames=list(letters[1:3], LETTERS[1:5]))

