Originally posted by: CAZ_88

Hi,

Context:

I'm using CPLEX's network optimizer to solve transportation problems inside a branch-and-cut process. Moreover, I am actually declaring these transportation problems using a network object and solving with CPLEX's netsolver which in the past has provided a significant speed up in time. However, in a few of the instances, the network solver takes excessively long and then concludes that the problem is unbounded, which in my case, I know would never be the case. I wanted to do further analysis as to what could be the reason for this and so...

Question:

-Is there a way to write the problem into an .lp file. Similar to CPXwriteprob, but for a network object?

-Any ideas as to why the network solver would conclude that the network problem is unbounded?

Thanks in advance.

-Is there a way to write the problem into an .lp file. Similar to CPXwriteprob, but for a network object?

You can use CPXNETwriteprob for that.

-Any ideas as to why the network solver would conclude that the network problem is unbounded?

I don't have an answer for that, but if you can share your model here it should be easier for others to help you.