GAMS does not recognise Gurobi license with Frozen Solve

GAMSPy
1

Hi all,

I encountered a problem with GAMS recognition of the Gurobi license under Frozen Solve. I have a large model (+ 1 million non-zeros), which I use Gurobi (for which I have an academic license) and Cplex to solve. For a regular solve, both work fine. Yet, I also try to solve it iteratively for different cases using Frozen Solve capability. While with CPLEX it works well, with Gurobi, I started getting an error:

*** Gurobi is not included in your license, and the model size exceeds the demo license limits.
*** To update your license, please contact your distributor.

When I solve small example problems under the license limit, they do solve, but I see a message in the output:

GAMS/Gurobi demo/community requires a Gurobi license from Gurobi Optimization.

I was able to reproduce this error with a large LP Example model from the GAMS library, which is attached below.

Corporate_Gurobi_Frozen_solve.inc (7.1 KB)

I would be grateful for your advice on that.

Best regards,

Adam

2

You can send an email to support@gams.com to get the necessary license to solve big models with frozen solve feature for the moment. You will be able to just use your GAMSPy license in the next release.

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