Dear Ampl Google Group members,

I have encountered an issue while using Ampl and would appreciate some guidance and advice. I have familiarized myself with the solve_result codes, where the numerical values interpret different outcomes. However, when I attempt to set a time limit, I come across two scenarios: “Time limit, without a feasible solution” and “Time limit, feasible solution,” and both of them display “limit” as their solve_result. This has left me somewhat puzzled.

As per my understanding, the numerical interpretations are as follows:

0-99: Optimal solution found

100-199: Solution found, possibly optimal, but errors might exist

200-299: Infeasible constraints cannot be satisfied

300-399: Unbounded objective, can be improved without limit

400-499: Solve terminated due to a user-set limit (e.g., iterations)

500-599: Solve terminated due to an error condition in the solver

However, when setting a time limit, I am unable to distinguish between “Time limit, without a feasible solution” and “Time limit, feasible solution” as both of their solve_results are “limit.” I would like to know if there is a way to more accurately differentiate these two scenarios so that I can take appropriate actions to improve my model.

If anyone can provide suggestions or sample code on how to address this issue, I would greatly appreciate it.

Thank you for your assistance!

Best regards,