Forum Discussion
QCQP model doomed infeasible in presolve, however it is not
Hi, I am trying to solve a QCQP model, which is doomed infeasible by the pre-solver. However, when solving with presolve deactivated it solves fine - just takes a very long time! Calling the IIS doe...
Hi Tristan,
Thank you for a quick reply. Please, find the mps-fil attached.
Neither can I reproduce the infeasibility using the lp. We are using the .Net api, and original this problem is formulated as a MIP and solved, then the integer variables are fixed using upper bound = lower bound, the quadratic terms are added the objective functions and quadratic constraints added to the model and the model is solved using the XPRBprob.lpOptimise.
You are right, that there is a difference between the lp and the log, however I ensure they are from the same state of the model, the exportProb is called just before lpOptimise. Besides the number of rows, the MIP entities numbers are different. Maybe the state of the model in memory in the .Net differs is not as the lp dumped?
I cannot find anything wrong with AVVAVV2Mode6AFRRVerticalUpCondensing2_23, unless it just picks one row out of many.
Let me know if you need anything else.
Thanks!