I am trying to solve a large optimization problem where I have a set of nodes on a road network that need to be connected using fibre using the shortest possible amount of fibre.
The problem is a classical Steiner tree problem. Grass has a function called v.net.steiner but my road network consists of 20,000 edges connecting intersections and the number of Steiner nodes (points to be connected by fibre) is about 1500. I tried this on a 32-bit Linux OS with 4 GB of memory and I got an out of memory error.
Any suggestions on how to solve this with a desktop PC - or do I need to send the problem to a super-computer
I've attached an image of the problem - don't worry I will trim the dangle-roads but that only shaves off about 1000 road segments