Size limits even with the free open-source solvers

New to AMPL
1

Hi,

I’m trying to run a MILP problem and I receive the error message:

Sorry, a demo license is limited to 300 variables and

300 constraints and objectives.

You have 340 variables, 128 constraints, and 1 objective.

exit value 1

I requested trials for several solvers in order to try to fix this but none of them seem to work.
Gurobi solver runs for a while but eventually it will run into the same problem, while the open source solvers fail immediately. I’m using the community academic version.
Is there a workaround for this with in the limits of the community academic edition?
I updated the .lic file also after installation

1 Like
2

Hi @ibuh ,

You need to activate your license first: just get the uuid of your license and run

python -m amplpy.modules activate <license-uuid>

(More on installation here: How to Install AMPL — AMPL Resources)