Initializing help system before first use

HEURSEARCHCOMBINESTRATEGY

Description
Strategy control for the Combine ( C) large neighborhood search heuristic, which uses a neighborhood set up through the combination of multiple integer solutions.
Type
Integer
Topic area
Heuristics
Values
-2 
XPRS_HEURSEARCHSTRATEGY_AUTOENFORCED Automatic enforced. The Optimizer determines the frequency and effort of this heuristic, ignoring the value of HEURSEARCHSTRATEGY.
-1 
XPRS_HEURSEARCHSTRATEGY_AUTOMATIC Automatic. The Optimizer determines the frequency and effort of this heuristic.
0 
XPRS_HEURSEARCHSTRATEGY_OFF Disabled.
1 
XPRS_HEURSEARCHSTRATEGY_CONSERVATIVE Conservative strategy; the heuristic is run less frequently than the default.
2 
XPRS_HEURSEARCHSTRATEGY_MODERATE Moderate strategy; default level of frequency and effort.
3 
XPRS_HEURSEARCHSTRATEGY_AGGRESSIVE Aggressive strategy; the heuristic is run more frequently than the default.
Default value
-1
Notes
At a moderate strategy, the LNS heuristics obey any user-specified value for HEURSEARCHROOTCUTFREQ and/or HEURSEARCHFREQ exactly. However, setting an LNS heuristic to a conservative (aggressive) strategy will lead to a less (more) frequent execution during the root cut loop and/or during the tree search than mandated by the frequency controls. Note that the effective frequency and effort applied by the chosen strategy are also influenced by HEUREMPHASIS.
The control value -2 ( XPRS_HEURSEARCHSTRATEGY_AUTOENFORCED) behaves like automatic selection (value -1, XPRS_HEURSEARCHSTRATEGY_AUTOMATIC), but, unlike -1, the value -2 is not overridden by the meta control HEURSEARCHSTRATEGY. For instance, setting 
    HEURSEARCHSTRATEGY = 0
    HEURSEARCHCOMBINESTRATEGY = -2
will disable all other LNS heuristics, but enforce the default behavior of the C heuristic.
Affects routines
XPRSmipoptimize ( MIPOPTIMIZE).
See also
HEURSEARCHSTRATEGY, HEUREMPHASIS, HEURSEARCHEFFORT, HEURSEARCHROOTCUTFREQ, HEURSEARCHFREQ.
Category
Control

Parent Topic Control Parameters

© 2001-2026 Fair Isaac Corporation. All rights reserved. This documentation is the property of Fair Isaac Corporation (“FICO”). Receipt or possession of this documentation does not convey rights to disclose, reproduce, make derivative works, use, or allow others to use it except solely for internal evaluation purposes to determine whether to purchase a license to the software described in this documentation, or as otherwise set forth in a written software license agreement between you and FICO (or a FICO affiliate). Use of this documentation and the software described in it must conform strictly to the foregoing permitted uses, and no other use is permitted.