I would like to run a solvers comparison on several instances of MINLPLib. I can get the .NL files for each instance. Now, I would like to reformulate several instances and I need to edit the .NL files (in particular I would like to add a term to the objective function). I would ask you if you know an easy way to read and modify directly the .NL files for instance using JuMP.
Thanks very much for all your help.