Xpress Update 8.13.7

Community Manager

4 years ago

Xpress Update 8.13.7 is now available on box.com for Window, Linux, MacOS and Solaris on x86-64 and Linux on AArch64, from

Click here to access

This is the latest update for the Xpress 8.13 release branch. Please note that the Windows, Linux or Solaris archives must be extracted over a prior installation of FICO Xpress 8.13. This update requires an Xpress 8.13 license.

Release Notes:

New in Release 8.13.7

Xpress Kalis 13.2.2

Start-based durations: the duration of a task variable can now be set depending on the start of the task and on a potential assignment of the task to a resource.
This can be used, for example, to model different durations between shifts or to model pre-emptive/soft breaks.

Xpress Mosel 5.8.2

kalis 13.2.2

Start-based durations: New subroutines 'set_start_based_duration', 'update_duration_with_idle_times', vset_duration_with_idle_times', 'get_start_based_duration'.
For alternative scheduling, durations conditional to assignment can be now specified with the 'setduration' procedure.
New procedure 'cp_show_var_constraints' to show constraints connected to a specific variable.
New parameter 'KALIS_NB_SOLUTIONS' to retrieve the number of solutions found.
It is now possible to specify generic user-defined constraints with subroutine references (operator '->').

Fixed in Release 8.13.7

Xpress Optimizer 39.01.08

Fixed an issue in presolve that could introduce small constraint violations.
In case a callback returns a non-zero error code, the remaining callbacks of the same type with smaller priority will no longer be called. This only affects use cases where multiple callbacks of the same type are registered.
Fixed an issue with piecewise-linear constraints when presolve was off and the first/last breakpoint was inside the bound interval of the input variable which could lead to incorrect results.
Fixed an issue with convex/concave piecewise-linear functions in combination with other pieciewise-linear functions with fixed outcome that could lead to incorrect results.
Fixed an issue in the integer presolver related to protected rows.
Fixed an issue in presolve for mixed-integer quadratic problems.
Fixed an issue in user interruption through a non-zero return code from the barlog callback.

Xpress Nonlinear 39.01.08

Fixed an issue where some information from the previous solve was lost when calling XSLPmaxim with the c/continue flag.
Fixed an issue where solutions might have incorrectly been rejected due to an incorrect objective computed from an objective transfer row.
The return values of the drcol, itervar and construct callbacks are no longer incorrectly interpreted as error codes.
Fixed an issue where the KEEPBEST bit of XSLP_FILTER was not correctly obeyed.
Fixed an issue in postsolve that could lead to failures.
Fixed an issue where terms could incorrectly be dropped when nonlinear presolve was disabled.

Xpress Kalis 13.2.2

Fixed bug in solutions sharing of two phases scheduling approach (solutions might not be shared between phases).
Fixed bug on inconsistency diagnostic (crash was happening when trying to solve an inconsistent problem).
Fixed crash when returning an invalid index in a custom branching scheme heuristic.
Fixed crash when using division operator on linear terms.