[FlopCpp] Reoptimizing a model with changed constants

[Christian Plum]

Hi All,

I have implemented a MIP-model in flopc++ and is solving it using COIN -
CBC.

After solving the model initially:

        modelInstance.minimize();

I wish to change my problem using:

        modelInstance->cost.value(&t_cost[0][0]);

and reoptimize it, to find a new solution adjusted to the changed constants:

        modelInstance.minimize();

My problem is that this second call returns infeasible *sometimes*. And even
if i call minimize() twice following each other will the second minimization
be infeasible:

        modelInstance.minimize();
        modelInstance.minimize();

So my current approach is to call:

        modelInstance.detach();
        modelInstance.attach(new OsiCbcSolverInterface);
        modelInstance.minimize();

But I was hoping there was a way to reuse information from the initial model
to resolve the second model...



Best Regards

Christian
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