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Jeff_z
Apr 6, 2016, 11:52:48 AM4/6/16
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I am trying to using cplex to optimize linear programming problem, and got two questions,
Is there any flags to indicate the results of the optimization, to check whether it is feasible or not?
What is the meaning of "Removing shift (1).", shown in the results? The results seems not the same as expected.
Johan Löfberg
Apr 6, 2016, 12:04:09 PM4/6/16
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http://users.isy.liu.se/johanl/yalmip/pmwiki.php?n=Tutorials.Basics
Removing shift sounds like some solver print out. Nothing from YALMIP
Erling D. Andersen
Apr 7, 2016, 4:14:33 AM4/7/16
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If you want to check feasibility you should just set objective function 0. So no special flag is needed for that.
Removing shift most likely something to do the degeneracy handling in the simplex optimizers.
Johan Löfberg
Apr 7, 2016, 5:42:28 AM4/7/16
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I think Jeff is asking about diagnostics flags etc, i.e., the "problem" field in the output from optimize, which is based on the feasibility report from the solver.
Jeff_z
Apr 7, 2016, 10:18:18 AM4/7/16
to YALMIP
Many thanks. your information is very useful. Sometimes when the problem is infeasible, no remind or warning in Matlab command windows is provided to clearly state that the problem is infeasible. Thus the flag would be very helpful. Thanks, Prof.
Johan Löfberg
Apr 7, 2016, 11:22:05 AM4/7/16
to YALMIP
You should always use the diagnostic flags to evaluate the solution process and act accordingly
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