Decision Optimization

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  • 1.  CPLEX Multiobjective problems - Error 1031

    Posted Wed August 21, 2024 03:16 PM

    Hi everyone.
    I'm a new user of CPLEX. I have two objective functions with different variables. It worked well if I included each function independently. I want to solve a multiobjective problem, however, when I used staticLex on both functions, it returned error 1031.

    #define CPXERR_NOT_FOR_QCP 1031
    Function is not available for quadratically constrained problems.


    Any suggestions? 
    Thank you.



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    Anh Chi Tuan
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  • 2.  RE: CPLEX Multiobjective problems - Error 1031

    IBM Champion
    Posted Wed August 21, 2024 03:43 PM

    If you dig into the documentation for CPXERR_NOT_FOR_MULTIOBJ you will find the following: "Quadratic terms are not permitted in any of the objectives or in the constraints." So your best (only?) hope for combining the objectives may be using a weighted combination of them as the single objective.



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    Paul Rubin
    Professor Emeritus
    Michigan State University
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  • 3.  RE: CPLEX Multiobjective problems - Error 1031

    Posted Sun August 25, 2024 11:29 PM
    Edited by Lorraine Rizzuto 25 days ago

    The error `CPXERR_NOT_FOR_MULTIOBJ` indicates that quadratic terms are not allowed in any of the objectives or constraints when using multiple objectives in an optimization model. The recommended approach to combining multiple objectives under this constraint is to create a single objective by forming a weighted combination of the original objectives. This way, you can still optimize for multiple criteria by adjusting the weights to reflect their relative importance.

    Moreover, Linking this concept to the "Dutch Bros Menu with Prices," decision optimization can help the company determine the ideal pricing strategy and menu offerings to maximize profits while meeting customer preferences and operational constraints. By analyzing factors such as ingredient costs, seasonal demand, and customer purchase patterns, Dutch Bros could use optimization techniques to decide which menu items to promote or adjust, ensuring a balanced and profitable menu lineup for the year.



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    jafar hansla
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