[SCIP] Inquiry About SCIP-Exact Solution Discrepancy for MIP Model

[Sedghi, Sepideh]

Dear SCIP Development Team,


I am a Ph.D. student at Worcester Polytechnic Institute (WPI). I recently installed SCIP-Exact 0.3 for my research to solve MIP models without roundoff errors. Although "ctest -R MIPEX" passed all the tests and confirmed a successful installation, I encountered unexpected behavior while solving a basic knapsack problem. With the exact mode disabled, SCIP provided the optimal solution of 14. However, with the exact mode enabled, SCIP returned a feasible but non-optimal solution of 0. I tried with a few other examples as well, and in all the examples SCIP returned a non-optimal solution with exact mode enabled. I have attached my model and a screenshot of the SCIP solution for your reference. Could you kindly provide insights on how to resolve the discrepancy?

Thank you for your time and assistance.

Best regards, Sepideh Sedghi
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