Julian Hall comments

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                                            Julian Hall

Re-solving many times with primal simplex can lead to basis issues (rare occurrence)

Hmmm... nasty

Re-solving many times with primal simplex can lead to basis issues (rare occurrence)

In both cases, the HiGHS simplex solver is unable to solve the LP because it has detected cycling. The simple solution is to force HiGHS to re-start from a logical...

Fix 1789

@galabovaa Definitely not for the new release! The CI failures that I've created look odd

Fix 1789

> Can I try IIS calculation already right now? I tried setting the option iis_strategy but did not see any effect. Is it possible to access IIS calculation from the...

highspy: Highs.val should work for highs_linear_expression

Closed by #1942

How to Set a Partial MIP Solution using setSolution()?

No, just a whole solution, with fractional values for any unknown binary variables A more sophisticated "sparse" representation of the values of integer variables to be used has been suggested,...

How to Set a Partial MIP Solution using setSolution()?

I'm now working on this, but am struggling to find the Gurobi documentation for the sparse solution - not that it's difficult to design a specification. Could you (easily) point...

How to Set a Partial MIP Solution using setSolution()?

Closed by #1843

How to Set a Partial MIP Solution using setSolution()?

I've added a check that if values are specified for fewer than 10% of the integer variables, then the sub-MIP isn't solved to get a feasible solution. I've just realised...

How to Set a Partial MIP Solution using setSolution()?

OK thanks. I'll go back and add the start node limit, and allow any positive number of fixed discrete variables - maybe logging a warning, particularly if the start node...