Edge Costs - Infinite

[ocetintas]

I am currently using your python solver. According to your documentation edge costs should be defined as floating numbers.

In my graph, I simply want to prevent some specific nodes from belonging to the same cluster. I am planning to do this by creating "edges with a really high negative cost" between nodes that should not be merged together.

• Do you think such an approach is possible with your solver?
• Does your python solver support np.inf and -np.inf as edge costs?

[aabbas90]

Hi, thanks for your interest.

1. RAMA does not support this function theoretically, it is because when we merge some nodes we do not check whether there is a constraint present disallowing such merger.
2. Practically if might be that assigning a high negative cost will disallow such mergers because of our dual message passing scheme. You can give it a try. However, the solver does not support infinities but possibly you can assign a value such as -10 * maximum absolute edge cost to disallow such mergers.