[SCIP] GCG, export restricted masters as .lp files

[Christian Puchert]

Hi Xavier,

this is not implemented directly. From the interactive shell, you could

  * abort with CTRL-C to get back to the shell
  * type "master" to switch to the master problem shell
  * type e.g. "write problem master.lp" to print your master problem

However, CTRL-C in GCG is a bit flaky.

Instead, you could add a SCIPwriteTransProb() call yourself to 
relax_gcg.c to print the restricted master; a good place would be right 
before or after the SCIPsolve(masterprob) call in l. 2308 (assuming you 
are using version 2.1.1).

For the pricing problems, you can achieve the same by calling 
SCIPwriteOrigProb() before solving a pricing problem, e.g. after l. 2306 
in pricer_gcg.cpp.

Note, however, that this would write your master problem at *every* node 
and the pricing problems at *every* iteration of the pricing loop, so 
you might want to restrict this.

Kind regards,
Christian


On 10.11.2016 21:37, Xavier Schepler wrote:
> Hello,
>
> With GCG, is there a way to export as .lp files some of the restricted
> masters during the column generation process ?
> In addition, is it possible to export as .lp files some of the pricing
> problems ?
>
> Kind regards,
>
> Xavier Schepler
>
>
>
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-- 
Christian Puchert, M.Sc.
Research Assistant

Chair of Operations Research
RWTH Aachen University
Kackertstr. 7
52072 Aachen
Germany
Tel: +49 (0)241 80-93380
Fax: +49 (0)241 80-92369
puchert at or.rwth-aachen.de
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