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Hi all,</div>
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I'm trying to use a combined objective function for a job-shop scheduling problem, where one part is linked to the distribution of the workload. The most logical options are to minimise the standard deviation or mean absolute deviation of the individual workload.
However, these would require either a square root or absolute value to be calculated from the product of a binary decision variable (SCIP linexpr) and some parameter which results in the exception "SCIP: a required plugin was not found".</div>
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What would be good options/alternatives here?</div>
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Kind regards,</div>
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Berry</div>
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