[Cbc] Multi Solutions for an LP solve using CBC solver

[Haroldo Gambini Santos]

Hi,

This options saves multiple solutions IF in the search process they are 
found.

In this case pre-processing already finds the optimal one, so the search 
stops.

Em 3/1/20 1:57 PM, Aby Subin escreveu:
> Hi all,
>
> As per the 
> https://list.coin-or.org/pipermail/cbc/2012-February/000766.html, we 
> are supporting multiple solutions in CBC. But on trying out a 
> sample/test lp file, it is not working as expected
> (tried with both disabling and enablign options for preprocessing, 
> heur, cutoff). The LP file content is as follows:
> "
>
> \Problem name:
>
> Minimize
>
> obj: 2 x0 + 5 x1 + 3 x2
>
> Subject To
>
> cons0:x0 + x1 + x2 = 1
>
> Bounds
>
> 0 <= x0 <= 1
>
> 0 <= x1 <= 1
>
> 0 <= x2 <= 1
>
> End
>
>
> "
>
>
> I was testing the same using CBC shell command. The list of commands 
> tries out as follows
>
>
> Coin:import test.lp
>
> Coin:maxSaved 3
>
> maxSavedSolutions was changed from 0 to 3
>
> Coin:cuts off
>
> Option for cutsOnOff changed from on to off
>
> Coin:heur off
>
> Option for heuristicsOnOff changed from on to off
>
> Coin:preprocess off
>
> Option for preprocess changed from sos to off
>
> Coin:solve
>
> Presolve 0 (-1) rows, 0 (-3) columns and 0 (-3) elements
>
> Empty problem - 0 rows, 0 columns and 0 elements
>
> Optimal - objective value 2
>
> After Postsolve, objective 2, infeasibilities - dual 0 (0), primal 0 (0)
>
> Optimal objective 2 - 0 iterations time 0.002, Presolve 0.00
>
> Coin:solu bestSol.txt
>
> Coin:nextB 1bestSol.txt
>
> All alternative solutions printed
>
>
>
> Could you please let me know on where I am missing the solutions?
>
>
> Regards
>
> Aby
>
>
> _______________________________________________
> Cbc mailing list
> Cbc at list.coin-or.org
> https://list.coin-or.org/mailman/listinfo/cbc

-- 
=============================================================
Haroldo Gambini Santos
Computing Department
Universidade Federal de Ouro Preto - UFOP
email: haroldo at ufop.edu.br
home/research page: www.decom.ufop.br/haroldo


It has long been an axiom of mine that the little things are infinitely
the most important.
-- Sir Arthur Conan Doyle, "A Case of Identity"