Graphviz---random node order and edges going through labels

Question

I have the following dot file:

digraph finite_state_machine {
    {
        rank=same;
        node [shape = doublecircle]; q_5;
        node [shape = circle];
        q_1 -> q_2 [ label = "." ];
        q_1 -> q_2 [ label = "\epsilon" ];
        q_2 -> q_1 [ label = "\epsilon" ];
        q_2 -> q_3 [ label = "a" ];
        q_3 -> q_4 [ label = "^\wedge a" ];
        q_3 -> q_4 [ label = "\epsilon" ];
        q_4 -> q_3 [ label = "\epsilon" ];
        q_4 -> q_5 [ label = "b" ];
    }
}

I was under the impression that the nodes would appear in the order they are mentioned. But the order seems random to me. I want the order, from left to right, to be in the order of the subscripts. Also, the edges go through the labels, how can I avoid that?

This is the current image:

Answer 1

Graphviz does lay out the nodes depending on the edge between each other, and not in order of appearance. If you want an edge not to influence the position of any node, you can do this by adding constraint=false.

Therefore, this graph:

digraph finite_state_machine {
  pad=0.2;
    {
        rank=same;
        node [shape = doublecircle]; q_5;
        node [shape = circle];
        q_1 -> q_2 [ label = "." ];
        q_1 -> q_2 [ label = "\epsilon", constraint=false ];
        q_2 -> q_1 [ label = "\epsilon", constraint=false ];
        q_2 -> q_3 [ label = "a" ];
        q_3 -> q_4 [ label = "^\wedge a" ];
        q_3 -> q_4 [ label = "\epsilon", constraint=false ];
        q_4 -> q_3 [ label = "\epsilon", constraint=false ];
        q_4 -> q_5 [ label = "b" ];
    }
}

Will get you:

I had to add pad in order to not have some of the labels cut off.