P = Poset(DiGraph({'a':['b'],'b':['c'],'c':['d']}), facade = True);P
P.comparability_graph() ------ cannot run
........ dot -Txdot file.dot | dot2tex > file.tex .............
P = Poset(DiGraph({'a':['b'],'b':['c'],'c':['d']}), facade = True);P
P.comparability_graph() ------ cannot run
........ dot -Txdot file.dot | dot2tex > file.tex .............