ObjBoundC not available

Answered

Comments

3 comments

  • Jaromił Najman

    Hi Gleb,

    Could you post the simple quadratic model, such that we can try to reproduce this issue? If possible, please post a small self-contained code.

    Best regards,
    Jaromił

    0
    Comment actions Permalink
  • Gleb Belov

    Hi Jaromił,

    the instance (recognized as convex quadratic, despite the equality) is this:

    Maximize
    obj
    Subject To
    p_times_0: - obj + [ x ^2 ] = 0
    Bounds
    x <= 10
    obj <= 100
    End

    When I call gurobi_cl ResultFile=result.json instance.lp, the json result file contains

    { "SolutionInfo": { "Status": 2, "Runtime": "3.2305717468261719e-04", "ObjVal": "100", "BoundVio": "0", "ConstrVio": "0", "IterCount": "0", "BarIterCount": 0}}

    i.e., ObjBound(C) are not there. For a slightly more complicated instance, which is also solved at root but at least requires 1 iteration of barrier, the bounds are there. I am happy to write C code but I think this shows the issue (if it is not the intended behaviour, but the documentation says nothing except that the attributes are intended for MIPs).

    Cheers, Gleb

    0
    Comment actions Permalink
  • Silke Horn

    Hi Gleb,

    Thanks for posting the example. The ObjBoundC attribute is not available since your model is not a MIP. If you change the type of one of your variables to integer, Gurobi will compute the ObjBoundC.

    Best regards
    Silke

    0
    Comment actions Permalink

Please sign in to leave a comment.

Powered by Zendesk