graphviz - Distribute nodes on the same rank of a wide graph to different lines

Question

I have a graph (organigram) how this:

digraph G {
nodesep=0.3;
ranksep=0.2;
margin=0.1;
node [shape=rectangle];
edge [arrowsize=0.8];
1 -> 2;
1 -> 3;
1 -> 4;
1 -> 5;
1 -> 6;
1 -> 7;
1 -> 8;
1 -> 9;
1 -> 10;
}

I have organigrams with 70 people and it's impossible to print in A4. How would I put nodes in 2 or 3 lines?

Answer 1

Here are two possibilities (see also this question):

1. Use the unflatten utility

Graphviz provides a tool called unflatten. If you pre-process your graph using this command line:

unflatten -l 3 wide.gv | dot -Tpng -o wide.png

the output image will be similar to the below picture. This is slightly less wide, and you may play with the -l option.

2. Use `rank=same' and invisible edges

You may use the standard techniques to make a automatically layed out graphs look more like you want it to:

• rank=same to group nodes in subgraphs and to define which nodes should be on the same line
• invisible edges to ensure that the different subgraphs appear on different ranks
• maybe some constraint=false for some edges to influence the layout
• group attributes of nodes to encourage straight edges.

The output graph will not necessarily be prettier...

Here's an example, you can probably do better. Also, this may not be very practical if the graph is generated dynamically.

digraph G {
nodesep=0.3;
ranksep=0.2;
margin=0.1;
node [shape=rectangle];
edge [arrowsize=0.8];


edge[style=invis];
node[group=a];
2->5->8;
node[group=b];
1->3->6->9;
node[group=c];
4->7->10;


edge[style=solid];
1 -> 2;
1 -> 3;
1 -> 4;
edge[constraint=false];
1 -> 5;
1 -> 6;
1 -> 7;
1 -> 8;
1 -> 9;
1 -> 10;
}