Xpress Updates 9.2.10 and 9.3.4

Community Manager

2 years ago

Xpress Updates 9.3.4 and 9.2.10 are now available on the client area for Windows, Linux and MacOS on x86-64, and Linux and MacOS on AArch64, from

https://clientarea.xpress.fico.com/download_patch.php#934
https://clientarea.xpress.fico.com/download_patch.php#9210

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 9.3.4 and 9.2.10

Xpress Optimizer 42.01.09

Fixed some multi-threading issues with the 'B' heuristic for MIPs.
Fixed an issue that could result in MIP callbacks being fired from a different thread than the main thread when setting CALLBACKFROMMASTERTHREAD=1 and THREADS=1.
Fixed an issue with presolving of MIPs with indicator constraints that could result in invalid tightenings.
Fixed an issue when setting OBJSCALEFACTOR for MIQPs that could result in a sub-optimal solution being returned.
Fixed an issue in the crossover which could cause a crash.
Fixed an issue where a wrong solution could be returned by XPRSgetlpsol in a preintsol callback fired before the initial LP relaxation has been solved.
Improved the numerical handling when presolving MIPs with very poorly scaled coefficients.
Fixed a deadlock that could occur when querying attribute values from callbacks.
Fixed an issue in the barrier algorithm which could cause a crash.
Fixed an issue where the LP relaxation solution was not available after a MIP solve that was completely presolved away.
Fixed an issue in the mod2 presolver.
Fixed a numerical issue in presolving that can lead to a wrong solution.
Improved numerical handling of large bound values.
Fixed an issue with restarts in component presolver.
Improved error message when a duplicate name error occurs.
In multi-objective problems, the beforeobjective and afterobjective callbacks are now fired for empty objectives with non-zero weight. Objectives with zero weight are considered disabled and will continue to be skipped.
Fixed an issue where the solution was sometimes unavailable when a multi- objective solve was interrupted after the first objective.
Fixed an issue with tolerances that could lead to incorrect cancellation of coefficients during presolve.

Xpress Nonlinear 42.01.09

Fixed an issue on problems with non-convex quadratic objective and pre-existing objective transfer row that could lead to wrong results.
Fixed a potential crash on nonlinear problems with binary rows with only a few repeating coefficients (where the configuration presolver would have been applied).
Fixed an issue with reading in .lp files with nonlinear coefficients like y * { x ^ 2 } <= 1 .
Fixed an issue that could lead to a wrong value for the objective transfer column when the objective coefficient was not +1.

Xpress Global 42.01.09

Fixed a potential crash on problems with complementarity constraints.

Xpress Interfaces 42.01.09 (Python, R, Matlab, .NET, Java)

Fixed an issue that caused API calls that change nonlinear formulas, to be recorded incorrectly when API recording is enabled.
Fixed a crash when calling XPRS.license(int) from Java and .NET.
[Python] Fixed some issues with problem.getcutlist. It will now correctly return the list of loaded cuts and return the number of cuts.
In Python, problem.getSolution now raises an error after interrupting a MIP solve before a solution is found.
On Intel platforms, the Python interface requires OpenMP 2024.1 or earlier, due to an incompatibility in 2024.2.

Xpress Mosel 6.4.7

mmxprs 4.2.3

'estimatemarginals' now raises an error if the problem is presolved, since the functionality is not available in that case
The constant part of objective sometimes had the wrong sign when formulated with mmquad
Fixed an error that occurred when a multi-objective problem has nlctr objectives but they are all linear