coin-or / Couenne

Convex Over and Under Envelopes for Nonlinear Estimation
Eclipse Public License 1.0
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Feasible problem marked as unfeasible, before algebraic simplification in the cost function #69

Open guillaumeiooss opened 1 year ago

guillaumeiooss commented 1 year ago

Hello,

When investigating a problem with my tool (to figure out why Couenne was marking it as unfeasible when it was supposed to have a solution), I encountered a peculiar situation:

[Cf the attached .mod file] (i) When using the first cost function (which is commented, line 14), Couenne marks the problem as unfeasible (ii) When using the second cost function, obtained by simplifying the "TX_2" on both sides of one of the fractions, the problem becomes feasible. (for reference, the problem is indeed feasible)

Therefore, would it be possible to add a preprocessing step or a fix to manage this issue?

Thank you for your support, Guillaume I.

Couenne_inf_probl_ttile_ioopt_handmod.txt