Marc, Thank you for interest in glpk and its modeling language.
> When I read the documentation, it appears that the AMPL like > abilities in GLPK do not include the for-loop control structures. In > particular, there is very little you can do after the solve > command (basically you can use display and print, but there is > no facility for examining the solution and rerunning the linear or > integer program). > > In real applications of linear and integer programming, I almost > always need some post-solution control due to either: > > (1) Decomposition techniques (such as column generation) > > (2) Having the linear program only able to approximate the > real-world problem. In this case, the solutions need to be analyzed > and the linear program needs to be adjusted several times before an > acceptable solution that fits the real-world constraints is > obtained. > > So my number #1 wish for Andrew is to add in the same type (or > better) post-solution control that AMPL has. There is a dilemma, because I do not think that mixing modeling and "programming" capabilities within model description (as in AMPL) is a good idea; on the other hand I would like to keep compatibility between GNU MathProg and AMPL. Probably, there must be another level, something like a script, that allows performing all operations needed for reoptimization and post-optimal processing. In principle, optimization results could be written to a file in the form of data section and used in other (or the same) model to perform reoptimization or post-optimal processing. This is not an elegenat way, however, it is in the spirit of "programming". :) Andrew Makhorin _______________________________________________ Help-glpk mailing list Help-glpk@gnu.org http://lists.gnu.org/mailman/listinfo/help-glpk