Xpress Update 8.12.4

Community Manager

5 years ago

Xpress Update 8.12.4 is now available for Windows, Linux, Mac and Solaris, fromhttps://clientarea.xpress.fico.com/download_patch.php#8124.

This is the latest update for the Xpress 8.12 release branch. Please note that the Windows, Linux, or Solaris archives must be extracted over a prior installation of FICO Xpress 8.12. This patch requires an Xpress 8.12 license.

Release Notes:

Xpress Optimizer 38.01.05

Fixed a performance issue in the GCD detection of continuous columns.
Fixed a bug in the LP reader which could lead to files with fixed columns not being read.
Special Ordered Sets will now be considered properly when detecting disconnected components for the concurrent component solve.
Fixed the single-line problem definition in the Python interface where the maximization sense was not read.
Fixed an issue in presolving that could lead to wrong row substitutions on numerically cumbersome instances.
Fixed an issue with scaling of quadratic problems that could result in very large-scale factors if the problem contains very small coefficients.
Fixed a further synchronization issue in parallel MIP that could result in a too high best bound being reported at the end of a solve.
Fixed an issue in big-M presolving that could cause incorrect matrix coefficients.
Fixed an issue with attention level prediction.
Fixed an issue that could prevent heuristics from finding solutions in presence of very small matrix coefficients.
Fixed an issue where the "No IP reductions" flag of PRESOLVEOPS would not be respected.
Fixed an issue with the interaction of dual reductions and variable eliminations.
Fixed an issue with parallel root heuristics.
New flag option 's' to XPRSwriteprtsol and console command printsol to include sensitivity analysis report for anlp solution when a basis is available.

Xpress Solver Interfaces 38.01.05(Python, R, Matlab, .NET, Java)

Fixed the cutoff value returned from the preintsol callback in the tsp.R example and the subtour detection algorithm in get_subtour.
Robustified convenience function xprs_loadproblemdata against wrong/missing user input.
[Python] Errors that occur in callback functions are raised when the solve terminates.
[Python] Fixed reference counting error when copying NumPy arrays containing Xpress objects.
[Python] Fixed an issue that prevented Knitro libraries from being loaded on Linux.
[Python] Corrected the return values of problem.getcoefformula and problem.getccoef.
[Python] Fixed an incorrect construction of the quotient of a function to a variable.

Xpress Mosel 5.6.2

Runtime Library

A potential memory corruption has been fixed in the handing of records when used in conjunction with model cloning.
An issue in the management of combined problems has been fixed.
A potential stack corruption has been fixed in the bim loader.

Mosel

Profiler: an issue has been fixed in the way timings for subroutines is accounted.
Debugger: test of equality now supported for textual and boolean values.
On Windows an issue has been fixed in the handling of message printing.

mmnl 2.4.1

Constraints without any variable no longer cause a program failure.mmxprs 3.2.1
A potential memory corruption has been fixed in 'loadbasis'.

mmodbc 3.10.2

mmsqlite: an issue has been fixed in the handling of non-ascii data.mmxml 2.2.7
A dedicated error message is now reported in case too many nodes are requested (instead of 'out of memory').