Colon                  package:base                  R Documentation

_C_o_l_o_n _O_p_e_r_a_t_o_r

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

     Generate regular sequences.

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

     from:to
        a:b

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

    from: starting value of sequence.

      to: (maximal) end value of the sequence.

    a, b: 'factor's of same length.

_D_e_t_a_i_l_s:

     The binary operator ':' has two meanings: for factors 'a:b' is
     equivalent to 'interaction(a, b)' (except for labelling by 'la:lb'
     not 'la.lb').

     For numeric arguments 'from:to' is equivalent to 'seq(from, to)',
     and generates a sequence from 'from' to 'to' in steps of '1' or
     '1-'.  Value 'to' will be included if it differs from 'from' by an
     integer up to a numeric fuzz of about '1e-7'.

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

     For numeric arguments, a numeric vector.  This will be of type
     'integer' if 'from' and 'to' are both integers and representable
     in the integer type, otherwise of type 'numeric'.

     For factors, a factor.

_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:

     'seq'.

     As an alternative to using ':' for factors, 'interaction'.

     For ':' used in the formal representation of an interaction, see 
     'formula'.

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

     1:4
     pi:6 # real
     6:pi # integer

     f1 <- gl(2,3); f1
     f2 <- gl(3,2); f2
     f1:f2 # a factor, the "cross"  f1 x f2

