Hello, i've tried with both Baron and Couenne to solve my MINLP problem, and both of them failed. It's a problem of optimal allocation (through a binary variable, a) of certain equipment. I'm 100% sure my problem isn't infeasible, because i've tested it without the optimization part (by trial and error) and i can find several solutions to it.
-- I've attached the .mod, .dat and a .run files, if anyone can see what might be the issue here, on why they are failing to get a viable solution. For example, in my "manual" code, without the optimization, if i enforce that one, and only one equipment, should be allocated in the 10th position, i.e: a[10] = 1; and enforce a value to hs, like this: hs[10] = 5 (i.e hsmin = hsmax = 5) I should be getting a viable solution. What could be the issue here? Maybe while running the Branch and Bound tree, the solvers are removing some parts of the search espace? Thanks in advance! You received this message because you are subscribed to the Google Groups "AMPL Modeling Language" group. To unsubscribe from this group and stop receiving emails from it, send an email to [hidden email]. To post to this group, send email to [hidden email]. Visit this group at https://groups.google.com/group/ampl. For more options, visit https://groups.google.com/d/optout. codigo_17_barras.mod (5K) Download Attachment dados_codigo_17_barras.dat (35K) Download Attachment script_codigo.run (228 bytes) Download Attachment |
Can you send the .nl file for the problem? It can be generated after the "data" command in script_codigo.run with the line
-- write gprob; which results in a prob.nl file. Thanks, Pietro On Thursday, March 14, 2019 at 5:24:43 PM UTC, Murilo Souza wrote:
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Yes, here it is.
-- One thing to note: - I'm testing with w1 = w2 = 0, wich means, i'm only minimizing the summation of the allocation of equipments, through the summation of the binary variablesÂ a. I've tried with different values of barramin, barramax, hsmin and hsmax. Most of those tries, it says my problem is infeasible. But sometimes, it kept looking for a solution, but saying something like: Cbc0010I After 100 nodes, 26 on tree, 1e+050 best solution, best possible 2 (510.87 seconds) Wich doesn't make sense to me, since i know theres a better solution than that. Em sexta-feira, 15 de marĂ§o de 2019 09:04:35 UTC-3, Pietro Belotti escreveu:
You received this message because you are subscribed to the Google Groups "AMPL Modeling Language" group. To unsubscribe from this group and stop receiving emails from it, send an email to [hidden email]. To post to this group, send email to [hidden email]. Visit this group at https://groups.google.com/group/ampl. For more options, visit https://groups.google.com/d/optout. prob.nl (72K) Download Attachment |
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