line.graph              package:igraph              R Documentation

_L_i_n_e _g_r_a_p_h _o_f _a _g_r_a_p_h

_D_e_s_c_r_i_p_t_i_o_n:

     This function calculates the line graph of another graph.

_U_s_a_g_e:

     line.graph(graph)

_A_r_g_u_m_e_n_t_s:

   graph: The input graph, it can be directed or undirected.

_D_e_t_a_i_l_s:

     The line graph 'L(G)' of a 'G' undirected graph is defined as
     follows. 'L(G)' has one vertex for each edge in 'G' and two
     vertices in 'L(G)' are connected  by an edge if their
     corresponding edges share an end point.

     The line graph 'L(G)' of a 'G' directed graph is slightly
     different, 'L(G)' has one vertex for each edge in 'G' and two
     vertices in 'L(G)' are connected by a directed edge if the target
     of the first vertex's corresponding edge is the same as the source
     of the second vertex's corresponding edge.

_V_a_l_u_e:

     A new graph object.

_A_u_t_h_o_r(_s):

     Gabor Csardi csardi@rmki.kfki.hu, the first version of the C code
     was written by Vincent Matossian.

_E_x_a_m_p_l_e_s:

     # generate the first De-Bruijn graphs
     g <- graph.full(2, directed=TRUE, loops=TRUE)
     line.graph(g)
     line.graph(line.graph(g))
     line.graph(line.graph(line.graph(g)))

