> Hi! My optimization model is extended stepwise, that is, it is set-up
> and solved for a specific planning horizon and extended afterwards to
> cover more periods. This is done to simulate a rolling horizon
> environment. Therefore, in each simultion run the optimization model
> is extended with new constraints and variables. Only in under special
> circumstance some already inialized constraints in variable are
> superfluous. I would like to delete these not needed constraints and
> variables, because for large simulation instances the model exceeds
> the available RAM of my computer and Xpress terminates. There are a
> lot of not needed constraints, because preprocessing always reduces
> the problem size strongly.
> How do I delete constraints and variables? Does a corresponding
> function to "create" exist? Or could I use "sethidden"? I could image
> that the latter doesn't help to reduce memory usage...
> Thanks a lot!
