If solver hits time limit, is a solution output?

Answered

Sam Ganzfried

• February 04, 2020 14:32

I am just wondering if the time limit parameter is set and the algorithm hits the time limit, does it still output a solution (whatever the best/current iteration of the algorithm has produced)? Obviously it wouldn't be an optimal solution, but I am just wondering if an approximate solution is still output in this case.

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• Official comment

  

  Simranjit Kaur

  Gurobi Staff

  • December 06, 2024 00:50

  This post is more than three years old. Some information may not be up to date. For current information, please check the Gurobi Documentation or Knowledge Base. If you need more help, please create a new post in the community forum. Or why not try our AI Gurobot?.
• 

  Yuriy Zinchenko

  Gurobi Staff

  • February 04, 2020 23:44

  Yes, the incumbent (if such is found) will be accessible through 'x' field of you variables.

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  Sam Ganzfried

  • February 05, 2020 01:01

  

  

  

  I just tried an example where model.get(GRB.IntAttr.Status) had a value of 9 (TIME_LIMIT status),

  and when I call get(GRB.DoubleAttr.X)

  I get:

  Exception in thread "main" gurobi.GRBException: Error at GRBVar.get
  at gurobi.GRBVar.get(GRBVar.java:124)

   

   

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• 

  Yuriy Zinchenko

  Gurobi Staff

  • February 05, 2020 23:59

  You should check if the incumbent was found first, before querying for the X property.  You can do this by checking SolCount, https://www.gurobi.com/documentation/9.0/refman/solcount.html#attr:SolCount

  (please see our examples for more illustration in the online doc)

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