Hamiltonian cycles on directed graphs

*To*: mathgroup at smc.vnet.net*Subject*: [mg110136] Hamiltonian cycles on directed graphs*From*: "King, Peter R" <peter.king at imperial.ac.uk>*Date*: Thu, 3 Jun 2010 05:40:27 -0400 (EDT)

My understanding is that, currently, the Hamiltonian cycles function does not work properly on directed graphs. Is there a way round this? For example I have the directed graph z = {a(r)b,a(r)d,b(r)c, b->i,c (r)a,c (r)k,d(r)e,d(r)g,e(r)f,e(r)c,f(r)d,f(r)l,g(r)h,g(r)a,h(r)i,h(r)f,i(r)g,i(r)j,j(r)l,j(r)b,k(r)j,k(r)e,l(r)k,l(r)h}; for which I would like the Hamiltonian cycles (can I specify which vertex I start from - although this is unimportant in this example). One small point, I can plot this in 2D and get arrows to show the directionality but in 3D I am struggling. Thanks