Topic
3 replies Latest Post - ‏2013-04-26T14:23:47Z by GGR
CedricVB
CedricVB
5 Posts
ACCEPTED ANSWER

Pinned topic Multiple objectives

‏2013-04-16T16:38:12Z |

Hello,

In our CP model, we would like to have multiple objectives:

 

minimize sum (<i,j> in Edges, m in Camions) Dist[<minl(i,j), maxl(i,j)>]*x[<i,j>,m];
maximize sum (k in Camions, <i,j> in Edges : i == k.position) x[<i,j>,k]*charge[j][k];
minimize sum (<i,j> in Edges, m in Camions) x[<i,j>,m]*(tempstrajet[<minl(i,j),maxl(i,j)>]+service[i][m]);

How does the CP optimizer handle multiple-objective optimization? Will it try to optimize the first objective first? Will it use Pareto?

Kind regards,

Cedric

  • GGR
    GGR
    56 Posts
    ACCEPTED ANSWER

    Re: Multiple objectives

    ‏2013-04-17T17:30:45Z  in response to CedricVB

    Hi Cedric

     

    You will find all information and an example about multi-objective optiimization in CPO  the documentation page of OPL

     

    in the item staticLex

     

    Hope that helps

  • CedricVB
    CedricVB
    5 Posts
    ACCEPTED ANSWER

    Re: Multiple objectives

    ‏2013-04-18T06:59:44Z  in response to CedricVB

    Thanks for your help,

    This documents the function "staticLex", but what will happen exactly when we use multiple minimize/maximize statements without using the staticLex function?

    Kind regards,

    Cedric

  • GGR
    GGR
    56 Posts
    ACCEPTED ANSWER

    Re: Multiple objectives

    ‏2013-04-26T14:23:47Z  in response to CedricVB

    Hi Cedric

    Semantically, it is a change of the model, so I would say it should take the last declared one (regarding the model as a procedural code). That is to have an effect a call to the solver (cp.solve or chained model in OPL) is required.

     

    Hope that helps