Xpress Update 9.3.1/9.2.7

Xpress Updates 9.3.1 and 9.2.7 are now available for Windows, Linux and Mac on x86-64 and Linux on AArch64, from:

https://clientarea.xpress.fico.com/download_patch.php#931
https://clientarea.xpress.fico.com/download_patch.php#927

These are the latest updates for the Xpress 9.3 and 9.2 release branches, respectively, and require matching licenses. Please note that these archives must be extracted over a prior installation of FICO Xpress 9.3 and 9.2, respectively.

Release Notes for both 9.3.1 and 9.2.7

Xpress Optimizer 42.01.06

• Fixed an issue with parallel root heuristics that could cause a crash on out-of-memory.
• Added a further stability check to presolve variable eliminations to avoid some numerical issues.
• Fixed an issue in the mod2 presolve reduction that can sometimes lead to incorrect results.
• Fixed an inefficiency in the QCQP solver.
• Fixed an issue where constant objectives in .lp files ended up with the wrong sign.
• Fixed a crash in the IIS algorithm.
• Fixed potential crash on out-of-memory.
• Fixed an issue primal simplex within a MIP solve that could result in solutions with a wrong objective for numerically challenging problems.
• Function XPRSloadlpsol now accepts NULL for all array elements, which will invalidate the current solution without loading a new one.

• Fixed an issue with quadratic problems where all non-convexities involved fixed columns.

• Fixed a crash in Python when a non-contiguous integer Pandas Series was passed to xpress.vars()
• Added a workaround for a known memory leak in NumPy: https://github.com/numpy/numpy/issues/25949

• Fixed use-after-delete in XPRBprob destructor in Java.

• A potential deadlock has been fixed in the handling of remote files.