Marc Vinyals

Would you consider adding support for optimization functions in OPB formulas? This would essentially involve adding a member variable and a corresponding method "set_optimization_target". If the target has been set...

According to https://www.cril.univ-artois.fr/PB12/format.pdf, OPB constraints should end in a semicolon. This is not a problem with many solvers, but other solvers such as SCIP are more picky and will not...

Currently calling `cnfshuffle -i file.cnf` prints a warning saying that it is waiting for a DIMACS file on stdin, even though it received the input correctly and it is working...

Should we allow multigraphs as input for Tseitin formulas? Currently we do not, but the only (technical) reason is that we do not know how to label multiedges. I do...

### Steps To Reproduce IntegerLattice.closest_vector() sometimes gives answers that seem off, even when the input vector is already in the lattice. The following code triggers the issue: ``` from sage.modules.free_module_integer...

Implements the changes suggested in #113. OPB instances have another member `_objective` which is just a list of pairs (coefficient, literal).