Decision Optimization

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  • 1.  Seems to be a small bug in java illonumvar getUB

    Posted Wed May 05, 2021 07:05 PM
    for some MIPs, such as janos-us-DDM , some integer variables appear as

    XHC(LD_LD_64.000000__L74)#71 >= 0   , ie there is no upper bound

    ilonumvar getUB () method returns -1, which can cause problems

    I am using the presolved version of the MIP, converted back to lp format so that I can read it easily

    I am using java API version 12.10

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    srinivas tamvada
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    #DecisionOptimization


  • 2.  RE: Seems to be a small bug in java illonumvar getUB

    Posted Thu May 06, 2021 04:45 AM
    I don't reproduce. Can you provide a sample (Java code + LP file) and your platform?

    On my side, I did the following:
    - write the presolved model of janos-us-DDM.mps.gz
    - read it back and write it as LP
    - read this LP from Java and iterate on variables to output the UB.
    I get ```Name = XHC(LD_LD_64.000000__L74)#71 1.0E20```



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    Vincent Beraudier
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    Original Message


  • 3.  RE: Seems to be a small bug in java illonumvar getUB

    Posted Thu May 06, 2021 07:47 AM
    my apologies, its a bug in my own code

    because the return value is a double, I was converting it to integer like below, and 1e20 is too big for a java integer

    IloNumvar var;
    ...
    (int)Math.round (var.getUB() )

    ------------------------------
    srinivas tamvada
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    Original Message