Installing COIN-OR for PuLP

Question

I have solved simple MILP problems with PuLP and I believe 'model.solve()' without any parameters refers to the default solver. But for harder problems, it keeps running and and I can't get a result. I'm wondering how I can install and add free solvers (ie not CPLEX or Gurobi) as a solver. I found COIN-OR but I couldn't find the right structure and documentation to use it. Any help would be greatly appreciated. Regards, Behrouz

Answer 1

1. Install the solver. This will depend on solver and your operating system, but should be fairly googleable.

2. Check its installed and pulp can access it by running:

   import pulp

   pulp.pulpTestAll()

This will try all solvers and confirm which available.

3. Solve your model using model.solve(solver) . For example model.solve(pulp.COIN_CMD())

More here: https://scaron.info/blog/linear-programming-in-python-with-pulp.html