Decision Optimization

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  • 1.  Pass CPLEX parameters when deploying LP/MPS model to WML

    Posted Mon March 18, 2024 11:40 AM

    I've loosely followed this example to deploy a MPS file to CP4D. All works well, however, for my actual model, I would like to have the ability to pass CPLEX parameters, such as for example a relative MIP gap. I've yet to find in the docs how this could be done. I'm not sure it is possible through the solver parameters, or at least I haven't figured out how to do it. Any ideas?



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    Florian Reichel
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  • 2.  RE: Pass CPLEX parameters when deploying LP/MPS model to WML

    Posted Tue March 19, 2024 10:55 AM

    Hi,

    as we can read in https://medium.com/@AlainChabrier/cplex-and-cpo-file-formats-with-do-experiments-in-cloud-pak-for-data-a2abf93c9c18

     Beside the LP file, it is still possible to add additional files, such as a .prm file to set some parameters to be taken into account when solving the model. Other types of additional files are possible such as MIP Starts.

    CPLEX supports the PRM file format for nondefault parameter settings.
    
    It is possible to read and write a file of parameter settings with the Callable Library. This kind of file is known as a PRM file. The file extension for a PRM file is .prm. The Callable Library routine CPXreadcopyparam reads parameter values from a file with the .prm extension. The routine CPXwriteparam writes a file of the current nondefault parameter settings to a file with the .prm extension. Here is the format of such a file: 


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    [Alex] [Fleischer]
    [Data and AI Technical Sales]
    [IBM]
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