Dear Alejandro,

1 - Call glpsol to generate a solution of the *LP* problem and save it
using "-w file.sol"
2 - The file.sol file must have a solution line (first) named "s" "bas", ie
a basic solution
3 - Call glpsol by disabling LP (--nopresol) and MILP preprocessing
(--nointopt) and include the base file (--ini file.sol)

$ glpsol -m localiz.mod -d localiz.dat --nopresol --nomip -w file.sol
$ glpsol -m localiz.mod -d localiz.dat --nopresol --nointopt --cuts --ini
file.sol

Andrew, for MIP problems I had the same problem: a file.sol with "mip"
solution, but Glpk display an error message:

"error: wrong solution designator; 'bas' expected"

Bests,
--
João Flávio de Freitas Almeida
Professor Adjunto
Departamento de Engenharia de Produção
Universidade Federal de Minas Gerais
30.310-290 Belo Horizonte MG Brasil



Em sáb, 7 de abr de 2018 às 11:07, Alejandro Pascual <alep...@gmail.com>
escreveu:

> Hello Chris,
>
> Thank you very much for your concern.
>
> I tried the --nopresol --nointopt options following your suggestion,
> but I got the following error message (I attach the log file):
>
> localiz0.sol:8: error: wrong solution designator; 'bas' expected
> Unable to read initial basis
>
> Best regards,
> Alejandro
>
> On 7 April 2018 at 10:12, Chris Matrakidis <cmatr...@gmail.com> wrote:
> > Hi Alejandro,
> >
> >>
> >> Anyway, I can't get glpsol to use the feasible solutition fed with
> >> --ini.
> >
> >
> > I think you need to disable the presolver with options --nopresol
> --nointopt
> > to use a given solution. The presolver generates a new problem, for which
> > the given solution is no longer valid.
> >
> > Best Regards,
> >
> > Chris Matrakidis
> _______________________________________________
> Help-glpk mailing list
> Help-glpk@gnu.org
> https://lists.gnu.org/mailman/listinfo/help-glpk
>
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