attr                  package:base                  R Documentation

_O_b_j_e_c_t _A_t_t_r_i_b_u_t_e_s

_D_e_s_c_r_i_p_t_i_o_n:

     Get or set specific attributes of an object.

_U_s_a_g_e:

     attr(x, which)
     attr(x, which) <- value

_A_r_g_u_m_e_n_t_s:

       x: an object whose attributes are to be accessed.

   which: a character string specifying which attribute is to be
          accessed.

   value: an object, the new value of the attribute.

_V_a_l_u_e:

     These functions provide access to a single attribute of an object.
      The first form returns the value of the named attribute.  The
     replacement form causes the named attribute to take the value
     specified.

     The first form first looks for an exact match to 'which' amongst
     the attributes of 'x', then a partial match.  If no exact match is
     found and more than one partial match is found, the result is
     'NULL'.

     Note that some attributes (namely 'class', 'comment', 'dim',
     'dimnames', 'names' and 'tsp') are treated specially and have
     restrictions on the values which can be set.

_R_e_f_e_r_e_n_c_e_s:

     Becker, R. A., Chambers, J. M. and Wilks, A. R. (1988) _The New S
     Language_. Wadsworth & Brooks/Cole.

_S_e_e _A_l_s_o:

     'attributes'

_E_x_a_m_p_l_e_s:

     # create a 2 by 5 matrix
     x <- 1:10
     attr(x,"dim") <- c(2, 5)

