graphviz样例

sametail

digraph g{
    rankdir=LR;
    edge[samehead=h1, sametail=t1];
    a1->b->c1;
    a2->b->c2;
    edge[samehead=h2, sametail=t2];
    a3->b->c3;
    a4->b->c4;
}

矩形边.gv

digraph G {
    graph [splines=ortho];
    node [shape=box, style="filled", color=white, fillcolor=lightgrey];
 
    a [label="a"];
    b [label="OK ?", shape=diamond, fillcolor=indianred];
    c [label="Error", style="rounded, filled"];
    d [label="b"];
 
    a -> b -> d;
    b -> c [taillabel="No", constraint=false, labeldistance=3];
    d:w -> a:w [taillabel="repeat", constraint=false, labeldistance=7];
 
    {rank = same; b; c;};
}