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I am exploring what the tradeoffs are between no crossover, crossover w/ default settings, and crossover with just dual for barrier optimization.

When I attempt to define my solver settings for the crossover with dual, I thought, based on the CPLEX documentation, that I would use the [barcrossalg] parameter and set it equal to 2. however, when I kick off a study, I get an error message back stating only the following parameters are available.

Is "barrier" the actual setting I am looking for and not barcrossalg?

I am using version 20.1.0 of CPLEX community edition.

Available options reported back to me by the solver:

advance, barrier,benders, clocktype, conflict, cpumask, defaults, dettimelimit, distmip, emphasis, feasopt, logfile, lpmethod, mip, multiobjective, network, optimalitytarget, output, parallel, paramdisplay, preprocessing, qpmethod, randomseed, read, record, sifting, simplex, solutiontype, threads, timelimit, tune, workdir, workmem

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2 Answers 2

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To use the barrier algorithm without crossover with cplex 20.1, you can use the following options:

  • set lpmethod 4 (this selects the barrier algorithm): enter image description here
  • set solutiontype 2 (this deactivates crossover): enter image description here

The log looks like this: enter image description here

You can see the barrier algorithm is indeed used. If you activate crossover, you can view some additional information: enter image description here

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  • $\begingroup$ thank you but i am able to get barrier w/o crossover. my question is how to do barrier w/ crossover but specifying dual only and not have the default settings, which uses both primal and dual. $\endgroup$
    – JBH_84
    Aug 26, 2022 at 14:53
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    $\begingroup$ You can refer to: ibm.com/docs/en/icos/… $\endgroup$
    – Samarth
    Aug 26, 2022 at 16:30
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If you are using the interactive optimizer, you need to type "set barrier crossover" (or just "set barrier" to get a list of available parameters related to the barrier method). When you type "set" to get a list of parameters, "barrier" refers to a submenu, not a single parameter. (Note the explanation: "set parameters for barrier optimization".)

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  • $\begingroup$ perfect! thank you for the explanation. i was able to get the setting defined. $\endgroup$
    – JBH_84
    Aug 26, 2022 at 16:45

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