Julian Hall comments

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                                            Julian Hall

HiGHS reports infeasible for LP models that Gurobi solve successfully

> Our benchmark runner downloads the LP/MPS files from cloud storage and renames it to a common `-` format before running: Goodness, how opaque!

Suspected memory leakage in highspy (python = 3.10)

What version of HiGHS are you using?

Suspected memory leakage in highspy (python = 3.10)

Great to see @BenChampion and @mathgeekcoder sparking off each other to investigate this! 🤩

When possible, ensure basis and internal solution are propagated when model status is `HighsModelStatus::kUnknown`

Yes, this is the anti-cycling test causing termination of the simplex solver with a dual infeasibility. Since that dual infeasibility is 1.3e-7, it's fair for a user to assume that...

`Highs::setCallback()` does not work in this case

Thanks for flagging this up. I'll look at it in due course. All the "H" characters you see are due to a unit test for the original logging callback that...

Incorrect declaration of infeasiblilty

It's very time-consuming to solve, and after 800s, Gurobi gives bounds of 1.2424e+07 1.2422e+07 0.01%

Stop MIP solve on `simplex_iteration_limit` (or other LP iteration limit) - Access iteration count via callback?

It's easy to put in, and I'll do it, but for MIP it doesn't strike me as a natural interrupt criterion - unlike LP.

Stop MIP solve on `simplex_iteration_limit` (or other LP iteration limit) - Access iteration count via callback?

Fixed by #1839

Make HiGHS callable directly from CVXPY and document the availability of HiGHS more explicitly

> * is the current SciPy not calling the updated version of HiGHS, or the user had an outdated version of SciPy? > > * what changes have been added...

Make HiGHS callable directly from CVXPY and document the availability of HiGHS more explicitly

> Since I am really not familiar with using HiGHS, I tried copy-pasting the code from the SciPy solver interface which also calls HiGHS. However, there seems to be many...