Graphviz: Place edge label on the other side

This may be related to How to place edge labels ON edge in graphviz: I have the following graph, which I visualize using the command dot -Teps g.dot > g.eps:

graph triple {
    node [shape=box]; User; Object; Tag;
    node [shape=开发者_如何学Pythondiamond,style=filled]; Triple;
    {
        User -- Triple [label = "1"];
        Object -- Triple [label = "1"];
    }
    {
        rank=same;
        User;
        Object;
    }
    Triple -- Tag [label="n"];
}

I would like the result to be more symmetric by putting the label between User and Triple on the left side of the graph.

Manual placement of edge labels cannot be done with graphviz.

However, you could use the headlabel, labeldistance and labelangle attributes:

graph triple {
node [shape=box]; User; Object; Tag;
node [shape=diamond,style=filled]; Triple;
    {
        User   -- Triple [headlabel = "1", labeldistance=2.5, labelangle=20];
        Object -- Triple [headlabel = "1", labeldistance=2.5, labelangle=-20];
    }
    {
        rank=same;
        User;
        Object;
    }
    Triple -- Tag [label="n"];
}

Output:

And here's the second workaround using splines=false and double edges:

graph {
splines=false;
node [shape=box]; User; Object; Tag;
node [shape=diamond,style=filled]; Triple;
    {
        User   -- Triple [label = "1"];
        User   -- Triple [label = ""];
        Object -- Triple [label = ""];
        Object -- Triple [label = "1"];
    }
    {
        rank=same;
        User;
        Object;
    }
    Triple -- Tag [label="n"];
}

Output: