Weight setting for Impossible to Cut


Like the previous poster, I'm trying to partition 3D FE mesh and I have a small, specific region that MUST be on the same processor. I was able to do this using very large weights early on, however I've recently moved into a 20 million node case and I believe the sum of my weights is going past the maximum possible integer value. I need to minimize communication between partitions, therefore I need to at least have edge weights of 1, but any value that doesn't cause an error seems to results in a partitioning which cuts through that region.

Is there a way in Parmetis-3.1 to absolutely prevent edgecuts in a region while still maintaining general edge weights? Currently I'm seeking to collapse all the vertices in the small section into a single graph point, but I'd prefer a simpler solution if possible. Any suggestions?


RE: The way to do this is to

The way to do this is to pre-process the graph and to combine all the nodes that you want to be together into a single node (whose weight will be the constituent weights). Using Metis's terminology, you need to
pre-coarsen the graph for those nodes that need to stay together.