Decision Optimization

Decision Optimization

Delivers prescriptive analytics capabilities and decision intelligence to improve decision-making.


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  • 1.  Set Start Point with Python API

    Posted 08/20/13 04:45 AM

    Originally posted by: 81XJ_Jakob_Kaths


    Hello,

    I'm using CPLEX to solve a MIQP problem in order to calculate control inputs for a model predictive control algorithm. Now I try to speed up my code and I was wondering if I could hand over a start point in each iteration as I always have a good guess for that because of my reciding control horizon. Is that possible using the Python API?

    Thanks!


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  • 2.  Re: Set Start Point with Python API

    Posted 08/20/13 06:03 AM

    I am not clear what you mean by "iteration".

    Using cplex.MIP_Starts.add() you can provide an initial integer feasible solution for the MIP search.

    If you want to provide a starting point for the algorithm that solves the node relaxation then you will have to use a solve callback.


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  • 3.  Re: Set Start Point with Python API

    Posted 08/20/13 07:05 AM

    Originally posted by: 81XJ_Jakob_Kaths


    Thanks, I will try that. By iteration I just mean that I recalculate the solution in a certain interval. But for each interval I already have a good guess that I want to provide as a start value.


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  • 4.  Re: Set Start Point with Python API

    Posted 08/20/13 09:08 AM

    Originally posted by: 81XJ_Jakob_Kaths


    Sorry, one more question. For the moment I want to use this for MIQP. Is it as well working for LP, MILP, QP, (MI)(QC)QP that way? Thanks in advance.


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  • 5.  Re: Set Start Point with Python API

    Posted 08/20/13 09:14 AM

    cplex.MIP_Starts is for everything that involves integral variables (and/or SOS constraints). For pure LP, QP, QCP, use cplex.start.


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