[Coin-discuss] GMPL support in COIN-OR

[Sebastian Nowozin]

Hello Michal and Bill,

Hart, William E wrote:

> I ran across this same issue several years ago when using GLPK directly.  I'm pretty sure that this is a limitation of GMPL, and not the interface of CBC or Symphony to it.

I have been using GLPK for some time and it definitely respects print
statements after the solve command.  For example, see the cute output of
the sudoku.mod model included in the GLPK distribution.

What I think is happening is that Cbc uses libglpk only to read in and
build the model, but does not have access or does not use anything that
comes after the solve command.

It would be really nice to have that feature (executing the commands
after solving).  In the long run, it would be even nicer to have the GNU
MathProg part factored out of GLPK into its own library under a COIN-OR
compatible license such that many solvers can access it directly.  But
this of course is up to the GLPK author, license-wise, and there are
many valid reasons to have it licensed under GPL-only.

Sebastian