

_S_e_q_u_e_n_c_e _G_e_n_e_r_a_t_i_o_n

     from:to
     seq(from, to)
     seq(from, to, by=)
     seq(from, to, length=)
     seq(along)

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

     The `:' and the first `seq(.)' form above generate the
     sequence `from, from+1', ..., `to'.  `seq' is a generic
     function.

     The second, `from, from+by', ..., `to'.  The third gen-
     erates a sequence of `length' equally spaced values
     from `from' to `to'.  The last generates the sequence
     `1, 2', ..., `length(along)'.

     If `from' and `to' are factors of the same length, the
     ``cross'' of the two is returned.

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

     The result is of `mode' `"integer"' if `from' is
     (numerically equal to an) integer.

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

     `rep', `sequence', `row', `col'.

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

     1:4
     pi:6 # float
     6:pi # integer

     seq(0,1, length=11)
     seq(1,9, by = 2) # match
     seq(1,9, by = pi)# stay below
     seq(1,6, by = 3)
     seq(1.575, 5.125, by=0.05)

     1:4
     pi:6 # float
     6:pi # integer

     seq(0,1, length=11)
     seq(1,9, by = 2) # match
     seq(1,9, by = pi)# stay below
     seq(1,6, by = 3)
     seq(1.575, 5.125, by=0.05)

     for (x in list(NULL, letters[1:6], list(1,pi)))
       cat("x=",deparse(x),";  seq(along = x):",seq(along = x),"\n")

     f1_ gl(2,3); f1
     f2_ gl(3,2); f2
     f1:f2 # a factor, the ``cross''  f1 x f2

     for (x in list(NULL, letters[1:6], list(1,pi)))
       cat("x=",deparse(x),";  seq(along = x):",seq(along = x),"\n")

     f1_ gl(2,3); f1
     f2_ gl(3,2); f2
     f1:f2 # a factor, the ``cross''  f1 x f2

