HiGHS Add irreducible inconsistent system (IIS) identification for LP

Jun 03 '24 12:06 jajhall

Hello jajhall, I got a infeasible model, so i tried to get iis of the model to analyze the problem. Find something about IIS in call_highs_from_python.py. While i was running call_highs_from_python.py, i got this:"h.setOptionValue("iis_strategy", highspy.IisStrategy.kIisStrategyFromLpRowPriority)AttributeError: module 'highspy' has no attribute 'IisStrategy'" Tring to help(highspy),didn't find any information about IIS. May I ask if the IIS functionality has been fully developed, and how should it be used?

Nov 05 '24 17:11 deyiaodiao

Sorry, some of the skeleton features for IIS were included in v1.8.0, but the proper calculation wasn't released

Nov 05 '24 22:11 jajhall

Thank you, looking forward to using IIS as soon as possible.

Nov 06 '24 01:11 deyiaodiao

Any new info on this topic?

Apr 03 '25 13:04 aurelije

I wish there were, but other developments have higher priority. Thanks for asking

Apr 03 '25 14:04 jajhall

hi @jajhall - I notice that although there is no info in the online docs, there seems to be some working functionality for IIS... I've got it working against a toy model of mine. How complete/stable do you think it is at this moment in time?

Edit: apologies I didn't pay attention closely enough to how recently you had already answered the comments above!

Apr 28 '25 18:04 ollie-bell