Control Parameters

Topics covered in this chapter:

Various controls exist within Xpress NonLinear to govern the solution procedure and the form of the output. Some of these take integer values and act as switches between various types of behavior. Many are tolerances on values related to the convergence criteria; these are all double precision. There are also a few controls which are character strings, setting names for structures. Any of these may be altered by the user to enhance performance of the SLP algorithm. In most cases, the default values provided have been found to work well in practice over a range of problems and caution should be exercised if they are changed.

Users of the Xpress NonLinear function library are provided with the following set of functions for setting and obtaining control values:


XSLPgetintcontrol	XSLPgetdblcontrol	XSLPgetstrcontrol
XSLPsetintcontrol	XSLPsetdblcontrol	XSLPsetstrcontrol

All the controls as listed in this chapter are prefixed with XSLP_. Most of them also exist within the Optimizer library with an NLP or SLP prefix, e.g., XPRS_NLPPRESOLVE. It is possible to use the above functions with other control parameters for the Xpress Optimizer (controls prefixed with XPRS_). For details of the Optimizer controls, see the Optimizer manual.

Example of the usage of the functions:

XSLPgetintcontrol(Prob, XSLP_PRESOLVE, &presolve);
printf("The value of PRESOLVE was %d\n", presolve);
XSLPsetintcontrol(Prob, XSLP_PRESOLVE, 1-presolve);
printf("The value of PRESOLVE is now %d\n", 1-presolve);

The following is a list of all the Xpress NonLinear controls:

XSLP_ALGORITHM, SLPALGORITHM	Bit map describing the SLP algorithm(s) to be used [ Bit-vector, SLP]
XSLP_ANALYZE, SLPANALYZE	Bit map activating additional options supporting model / solution path analysis [ Bit-vector, Logging, SLP]
XSLP_ATOL_A, SLPATOL_A	Absolute delta convergence tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_ATOL_R, SLPATOL_R	Relative delta convergence tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_AUGMENTATION, SLPAUGMENTATION	Bit map describing the SLP augmentation method(s) to be used [ Bit-vector, SLP]
XSLP_AUTOSAVE, SLPAUTOSAVE	Frequency with which to save the model [ Logging, SLP]
XSLP_BARCROSSOVERSTART, SLPBARCROSSOVERSTART	Default crossover activation behaviour for barrier start [ Linearizations, SLP]
XSLP_BARLIMIT, SLPBARLIMIT	Number of initial SLP iterations using the barrier method [ Limits, Linearizations, SLP]
XSLP_BARSTALLINGLIMIT, SLPBARSTALLINGLIMIT	Number of iterations to allow numerical failures in barrier before switching to dual [ Limits, Linearizations, SLP]
XSLP_BARSTALLINGOBJLIMIT, SLPBARSTALLINGOBJLIMIT	Number of iterations over which to measure the objective change for barrier iterations with no crossover [ Limits, Linearizations, SLP]
XSLP_BARSTALLINGTOL, SLPBARSTALLINGTOL	Required change in the objective when progress is measured in barrier iterations without crossover [ Linearizations, SLP]
XSLP_BARSTARTOPS, SLPBARSTARTOPS	Controls behaviour when the barrier is used to solve the linearizations [ Linearizations, SLP]
XSLP_BOUNDTHRESHOLD, SLPBOUNDTHRESHOLD	The maximum size of a bound that can be introduced by nonlinear presolve. [ Presolve, SLP]
XSLP_CALCTHREADS, NLPCALCTHREADS	Number of threads used for formula and derivatives evaluations [ Parallel]
XSLP_CASCADE, SLPCASCADE	Bit map describing the cascading to be used [ Cascading, SLP]
XSLP_CASCADENLIMIT, SLPCASCADENLIMIT	Maximum number of iterations for cascading with non-linear determining rows [ Cascading, Limits, SLP]
XSLP_CASCADETOL_PA, SLPCASCADETOL_PA	Absolute cascading print tolerance [ Cascading, Logging, SLP]
XSLP_CASCADETOL_PR, SLPCASCADETOL_PR	Relative cascading print tolerance [ Cascading, Logging, SLP]
XSLP_CDTOL_A, SLPCDTOL_A	Absolute tolerance for deducing constant derivatives [ Tolerances]
XSLP_CDTOL_R, SLPCDTOL_R	Relative tolerance for deducing constant derivatives [ Tolerances]
XSLP_CLAMPSHRINK, SLPCLAMPSHRINK	Shrink ratio used to impose strict convergence on variables converged in extended criteria only [ SLP]
XSLP_CLAMPVALIDATIONTOL_A, SLPCLAMPVALIDATIONTOL_A	Absolute validation tolerance for applying XSLP_CLAMPSHRINK [ SLP, Tolerances]
XSLP_CLAMPVALIDATIONTOL_R, SLPCLAMPVALIDATIONTOL_R	Relative validation tolerance for applying XSLP_CLAMPSHRINK [ SLP, Tolerances]
XSLP_CONTROL	Bit map describing which Xpress NonLinear functions also activate the corresponding Optimizer Library function [ Bit-vector]
XSLP_CONVERGENCEOPS, SLPCONVERGENCEOPS	Bit map describing which convergence tests should be carried out [ Bit-vector, SLP, SLP-convergence]
XSLP_CTOL, SLPCTOL	Closure convergence tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_CUTSTRATEGY, SLPCUTSTRATEGY	Determines whihc cuts to apply in the MISLP search when the default SLP-in-MIP strategy is used. [ Cuts, MISLP]
XSLP_DAMP, SLPDAMP	Damping factor for updating values of variables [ SLP]
XSLP_DAMPEXPAND, SLPDAMPEXPAND	Multiplier to increase damping factor during dynamic damping [ SLP]
XSLP_DAMPMAX, SLPDAMPMAX	Maximum value for the damping factor of a variable during dynamic damping [ SLP]
XSLP_DAMPMIN, SLPDAMPMIN	Minimum value for the damping factor of a variable during dynamic damping [ SLP]
XSLP_DAMPSHRINK, SLPDAMPSHRINK	Multiplier to decrease damping factor during dynamic damping [ SLP]
XSLP_DAMPSTART, SLPDAMPSTART	SLP iteration at which damping is activated [ SLP]
XSLP_DEFAULTIV, NLPDEFAULTIV	Default initial value for an SLP variable if none is explicitly given [ Data Input]
XSLP_DEFAULTSTEPBOUND, SLPDEFAULTSTEPBOUND	Minimum initial value for the step bound of an SLP variable if none is explicitly given [ SLP]
XSLP_DELAYUPDATEROWS, SLPDELAYUPDATEROWS	Number of SLP iterations before update rows are fully activated [ SLP]
XSLP_DELTA_A, SLPDELTA_A	Absolute perturbation of values for calculating numerical derivatives [ Derivatives]
XSLP_DELTA_INFINITY, SLPDELTA_INFINITY	Maximum value for partial derivatives [ Derivatives]
XSLP_DELTA_R, SLPDELTA_R	Relative perturbation of values for calculating numerical derivatives [ Derivatives]
XSLP_DELTA_X, SLPDELTA_X	Minimum absolute value of delta coefficients to be retained [ Derivatives]
XSLP_DELTA_Z, SLPDELTA_Z	Tolerance used when calculating derivatives [ Derivatives, Tolerances]
XSLP_DELTA_ZERO, SLPDELTA_ZERO	Absolute zero acceptance tolerance used when calculating derivatives [ Derivatives, Tolerances]
XSLP_DELTACOST, SLPDELTACOST	Initial penalty cost multiplier for penalty delta vectors [ SLP]
XSLP_DELTACOSTFACTOR, SLPDELTACOSTFACTOR	Factor for increasing cost multiplier on total penalty delta vectors [ SLP]
XSLP_DELTAFORMAT, SLPDELTAFORMAT	Formatting string for creation of names for SLP delta vectors [ Logging, SLP]
XSLP_DELTAMAXCOST, SLPDELTAMAXCOST	Maximum penalty cost multiplier for penalty delta vectors [ SLP]
XSLP_DELTAOFFSET, SLPDELTAOFFSET	Position of first character of SLP variable name used to create name of delta vector [ Logging, SLP]
XSLP_DELTAZLIMIT, SLPDELTAZLIMIT	Number of SLP iterations during which to apply XSLP_DELTA_Z [ SLP]
XSLP_DERIVATIVES, NLPDERIVATIVES	Bitmap describing the method of calculating derivatives [ Derivatives]
XSLP_DETERMINISTIC, NLPDETERMINISTIC	Determines if the parallel features of SLP should be guaranteed to be deterministic [ MISLP, Parallel, SLP]
XSLP_DJTOL, SLPDJTOL	Tolerance on DJ value for determining if a variable is at its step bound [ SLP, Tolerances]
XSLP_DRCOLDJTOL, SLPDRCOLDJTOL	Reduced cost tolerance on the delta variable when fixing due to the determining column being below XSLP_DRCOLTOL. [ Cascading, SLP, Tolerances]
XSLP_DRCOLTOL, SLPDRCOLTOL	The minimum absolute magnitude of a determining column, for which the determined variable is still regarded as well defined [ Cascading, SLP, Tolerances]
XSLP_DRFIXRANGE, SLPDRFIXRANGE	The range around the previous value where variables are fixed in cascading if the determining column is below XSLP_DRCOLTOL. [ Cascading, SLP]
XSLP_ECFCHECK, SLPECFCHECK	Check feasibility at the point of linearization for extended convergence criteria [ SLP, SLP-convergence]
XSLP_ECFTOL_A, SLPECFTOL_A	Absolute tolerance on testing feasibility at the point of linearization [ SLP, SLP-convergence, Tolerances]
XSLP_ECFTOL_R, SLPECFTOL_R	Relative tolerance on testing feasibility at the point of linearization [ SLP, SLP-convergence, Tolerances]
XSLP_ECHOXPRSMESSAGES	Controls if the XSLP message callback should relay messages from the XPRS library. [ Logging]
XSLP_ENFORCECOSTSHRINK, SLPENFORCECOSTSHRINK	Factor by which to decrease the current penalty multiplier when enforcing rows. [ SLP]
XSLP_ENFORCEMAXCOST, SLPENFORCEMAXCOST	Maximum penalty cost in the objective before enforcing most violating rows [ SLP]
XSLP_ERRORCOST, SLPERRORCOST	Initial penalty cost multiplier for penalty error vectors [ SLP]
XSLP_ERRORCOSTFACTOR, SLPERRORCOSTFACTOR	Factor for increasing cost multiplier on total penalty error vectors [ SLP]
XSLP_ERRORMAXCOST, SLPERRORMAXCOST	Maximum penalty cost multiplier for penalty error vectors [ SLP]
XSLP_ERROROFFSET, SLPERROROFFSET	Position of first character of constraint name used to create name of penalty error vectors [ Logging, SLP]
XSLP_ERRORTOL_A, SLPERRORTOL_A	Absolute tolerance for error vectors [ SLP, Tolerances]
XSLP_ERRORTOL_P, SLPERRORTOL_P	Absolute tolerance for printing error vectors [ SLP, Tolerances]
XSLP_ESCALATION, SLPESCALATION	Factor for increasing cost multiplier on individual penalty error vectors [ SLP]
XSLP_ETOL_A, SLPETOL_A	Absolute tolerance on penalty vectors [ SLP, Tolerances]
XSLP_ETOL_R, SLPETOL_R	Relative tolerance on penalty vectors [ SLP, Tolerances]
XSLP_EVALUATE, NLPEVALUATE	Evaluation strategy for user functions [ User Functions]
XSLP_EVTOL_A, SLPEVTOL_A	Absolute tolerance on total penalty costs [ SLP, SLP-convergence, Tolerances]
XSLP_EVTOL_R, SLPEVTOL_R	Relative tolerance on total penalty costs [ SLP, SLP-convergence, Tolerances]
XSLP_EXPAND, SLPEXPAND	Multiplier to increase a step bound [ SLP]
XSLP_FEASTOLTARGET, SLPFEASTOLTARGET	When set, this defines a target feasibility tolerance to which the linearizations are solved to [ Linearizations, SLP, Tolerances]
XSLP_FILTER, SLPFILTER	Bit map for controlling solution updates [ Bit-vector, SLP, Solution]
XSLP_FINDIV, NLPFINDIV	Option for running a heuristic to find a feasible initial point [ Heuristics]
XSLP_FUNCEVAL, NLPFUNCEVAL	Bit map for determining the method of evaluating user functions and their derivatives [ Derivatives, User Functions]
XSLP_GRANULARITY, SLPGRANULARITY	Base for calculating penalty costs [ SLP]
XSLP_GRIDHEURSELECT, SLPGRIDHEURSELECT	Bit map selectin which heuristics to run if the problem has variable with an integer delta [ Heuristics, SLP]
XSLP_HESSIAN, NLPHESSIAN	Second order differentiation mode when using analytical derivatives [ Derivatives]
XSLP_HEURSTRATEGY, SLPHEURSTRATEGY	Branch and Bound: This specifies the MINLP heuristic strategy. [ Heuristics, SLP]
XSLP_INFEASLIMIT, SLPINFEASLIMIT	The maximum number of consecutive infeasible SLP iterations which can occur before Xpress-SLP terminates [ Limits, SLP]
XSLP_INFINITY, NLPINFINITY	Value returned by a divide-by-zero in a formula [ Numerics]
XSLP_ITERFALLBACKOPS, SLPITERFALLBACKOPS	Alternative LP level control values for numerically challengeing problems [ Linearizations, Numerics, SLP]
XSLP_ITERLIMIT, SLPITERLIMIT	The maximum number of SLP iterations [ Limits, SLP]
XSLP_ITOL_A, SLPITOL_A	Absolute impact convergence tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_ITOL_R, SLPITOL_R	Relative impact convergence tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_IVNAME, NLPIVNAME	Name of the set of initial values to be used [ File IO]
XSLP_JACOBIAN, NLPJACOBIAN	First order differentiation mode when using analytical derivatives [ Derivatives]
XSLP_KEEPEQUALSCOLUMN, NLPKEEPEQUALSCOLUMN	When set to a nonzero value, the MPS reader will keep the equals column in the problem [ Misc]
XSLP_LINQUADBR, NLPLINQUADBR	Use linear and quadratic constraints and objective function to further reduce bounds on all variables [ Presolve]
XSLP_LOG, NLPLOG	Level of printing during SLP iterations [ Logging, SLP]
XSLP_LSITERLIMIT, SLPLSITERLIMIT	Number of iterations in the line search [ Limits, SLP]
XSLP_LSPATTERNLIMIT, SLPLSPATTERNLIMIT	Number of iterations in the pattern search preceding the line search [ Limits, SLP]
XSLP_LSSTART, SLPLSSTART	Iteration in which to active the line search [ SLP]
XSLP_LSZEROLIMIT, SLPLSZEROLIMIT	Maximum number of zero length line search steps before line search is deactivated [ Limits, SLP]
XSLP_MATRIXTOL, SLPMATRIXTOL	Nonzero tolerance for dropping coefficients from the linearization. [ SLP]
XSLP_MAXTIME, NLPMAXTIME	The maximum time in seconds that the SLP optimization will run before it terminates [ Limits]
XSLP_MAXWEIGHT, SLPMAXWEIGHT	Maximum penalty weight for delta or error vectors [ SLP]
XSLP_MEMORYFACTOR	Factor for expanding size of dynamic arrays in memory [ Memory]
XSLP_MERITLAMBDA, NLPMERITLAMBDA	Factor by which the net objective is taken into account in the merit function [ SLP, Solution]
XSLP_MINSBFACTOR, SLPMINSBFACTOR	Factor by which step bounds can be decreased beneath XSLP_ATOL_A [ SLP]
XSLP_MINUSDELTAFORMAT, SLPMINUSDELTAFORMAT	Formatting string for creation of names for SLP negative penalty delta vectors [ Logging, SLP]
XSLP_MINUSERRORFORMAT, SLPMINUSERRORFORMAT	Formatting string for creation of names for SLP negative penalty error vectors [ Logging, SLP]
XSLP_MINWEIGHT, SLPMINWEIGHT	Minimum penalty weight for delta or error vectors [ SLP]
XSLP_MIPALGORITHM, SLPMIPALGORITHM	Bitmap describing the MISLP algorithms to be used [ Bit-vector, MISLP]
XSLP_MIPCUTOFF_A, SLPMIPCUTOFF_A	Absolute objective function cutoff for MIP termination [ MISLP, Tolerances]
XSLP_MIPCUTOFF_R, SLPMIPCUTOFF_R	Absolute objective function cutoff for MIP termination [ MISLP, Tolerances]
XSLP_MIPCUTOFFCOUNT, SLPMIPCUTOFFCOUNT	Number of SLP iterations to check when considering a node for cutting off [ Limits, MISLP]
XSLP_MIPCUTOFFLIMIT, SLPMIPCUTOFFLIMIT	Number of SLP iterations to check when considering a node for cutting off [ Limits, MISLP]
XSLP_MIPDEFAULTALGORITHM, SLPMIPDEFAULTALGORITHM	Default algorithm to be used during the tree search in MISLP [ Linearizations, MISLP]
XSLP_MIPERRORTOL_A, SLPMIPERRORTOL_A	Absolute penalty error cost tolerance for MIP cut-off [ MISLP, Tolerances]
XSLP_MIPERRORTOL_R, SLPMIPERRORTOL_R	Relative penalty error cost tolerance for MIP cut-off [ MISLP, Tolerances]
XSLP_MIPFIXSTEPBOUNDS, SLPMIPFIXSTEPBOUNDS	Bitmap describing the step-bound fixing strategy during MISLP [ MISLP]
XSLP_MIPITERLIMIT, SLPMIPITERLIMIT	Maximum number of SLP iterations at each node [ Limits, MISLP]
XSLP_MIPLOG, SLPMIPLOG	Frequency with which MIP status is printed [ Logging, MISLP]
XSLP_MIPOCOUNT, SLPMIPOCOUNT	Number of SLP iterations at each node over which to measure objective function variation [ MISLP, SLP-convergence]
XSLP_MIPOTOL_A, SLPMIPOTOL_A	Absolute objective function tolerance for MIP termination [ MISLP, SLP-convergence, Tolerances]
XSLP_MIPOTOL_R, SLPMIPOTOL_R	Relative objective function tolerance for MIP termination [ MISLP, SLP-convergence, Tolerances]
XSLP_MIPRELAXSTEPBOUNDS, SLPMIPRELAXSTEPBOUNDS	Bitmap describing the step-bound relaxation strategy during MISLP [ MISLP]
XSLP_MSMAXBOUNDRANGE, MSMAXBOUNDRANGE	Defines the maximum range inside which initial points are generated by multistart presets [ Multistart]
XSLP_MTOL_A, SLPMTOL_A	Absolute effective matrix element convergence tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_MTOL_R, SLPMTOL_R	Relative effective matrix element convergence tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_MULTISTART, MULTISTART	The multistart master control. [ Multistart]
XSLP_MULTISTART_LOG, MULTISTART_LOG	The level of logging during the multistart run. [ Logging, Multistart]
XSLP_MULTISTART_MAXSOLVES, MULTISTART_MAXSOLVES	The maximum number of jobs to create during the multistart search. [ Limits, Multistart]
XSLP_MULTISTART_MAXTIME, MULTISTART_MAXTIME	The maximum total time to be spent in the mutlistart search. [ Limits, Multistart]
XSLP_MULTISTART_POOLSIZE, MULTISTART_POOLSIZE	The maximum number of problem objects allowed to pool up before synchronization in the deterministic multistart. [ Limits, Multistart]
XSLP_MULTISTART_SEED, MULTISTART_SEED	Random seed used for the automatic generation of initial point when loading multistart presets [ Multistart]
XSLP_MULTISTART_THREADS, MULTISTART_THREADS	The maximum number of threads to be used in multistart [ Multistart, Parallel]
XSLP_MVTOL, SLPMVTOL	Marginal value tolerance for determining if a constraint is slack [ SLP, SLP-convergence, Tolerances]
XSLP_NLPSOLVER, NLPSOLVER	Controls whether to call FICO Xpress Global or one of the local solvers [ Solution Process]
XSLP_OBJTHRESHOLD, SLPOBJTHRESHOLD	Assumed maximum value of the objective function in absolute value. [ SLP]
XSLP_OBJTOPENALTYCOST, SLPOBJTOPENALTYCOST	Factor to estimate initial penalty costs from objective function [ SLP]
XSLP_OCOUNT, SLPOCOUNT	Number of SLP iterations over which to measure objective function variation for static objective (2) convergence criterion [ SLP, SLP-convergence]
XSLP_OPTIMALITYTOLTARGET, SLPOPTIMALITYTOLTARGET	When set, this defines a target optimality tolerance to which the linearizations are solved to [ Linearizations, SLP, Tolerances]
XSLP_OTOL_A, SLPOTOL_A	Absolute static objective (2) convergence tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_OTOL_R, SLPOTOL_R	Relative static objective (2) convergence tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_PENALTYCOLFORMAT, SLPPENALTYCOLFORMAT	Formatting string for creation of the names of the SLP penalty transfer vectors [ Logging, SLP]
XSLP_PENALTYINFOSTART, SLPPENALTYINFOSTART	Iteration from which to record row penalty information [ Logging, SLP]
XSLP_PENALTYROWFORMAT, SLPPENALTYROWFORMAT	Formatting string for creation of the names of the SLP penalty rows [ Logging, SLP]
XSLP_PLUSDELTAFORMAT, SLPPLUSDELTAFORMAT	Formatting string for creation of names for SLP positive penalty delta vectors [ Logging, SLP]
XSLP_PLUSERRORFORMAT, SLPPLUSERRORFORMAT	Formatting string for creation of names for SLP positive penalty error vectors [ Logging, SLP]
XSLP_POSTSOLVE, NLPPOSTSOLVE	This control determines whether postsolving should be performed automatically [ Presolve]
XSLP_PRESOLVE, NLPPRESOLVE	This control determines whether presolving should be performed on the nonlinear problem prior to starting the main algorithm [ Presolve]
XSLP_PRESOLVE_ELIMTOL, NLPPRESOLVE_ELIMTOL	Tolerance for nonlinear eliminations during SLP presolve [ Presolve, Tolerances]
XSLP_PRESOLVELEVEL, NLPPRESOLVELEVEL	This control determines the level of changes presolve may carry out on the problem and whether column/row indices may change [ Presolve]
XSLP_PRESOLVEOPS, NLPPRESOLVEOPS	Bitmap indicating the SLP presolve actions to be taken [ Bit-vector, Presolve]
XSLP_PRESOLVEZERO, NLPPRESOLVEZERO	Minimum absolute value for a variable which is identified as nonzero during SLP presolve [ Presolve, Tolerances]
XSLP_PRIMALINTEGRALALPHA, NLPPRIMALINTEGRALALPHA	Decay term for primal integral computation [ Logging]
XSLP_PRIMALINTEGRALREF, NLPPRIMALINTEGRALREF	Reference solution value to take into account when calculating the primal integral [ Logging]
XSLP_PROBING, NLPPROBING	This control determines whether probing on a subset of variables should be performed prior to starting the main algorithm. [ Presolve]
XSLP_REFORMULATE, NLPREFORMULATE	Controls the problem reformulations carried out before augmentation. [ Presolve]
XSLP_SAMECOUNT, SLPSAMECOUNT	Number of steps reaching the step bound in the same direction before step bounds are increased [ SLP]
XSLP_SAMEDAMP, SLPSAMEDAMP	Number of steps in same direction before damping factor is increased [ SLP]
XSLP_SBLOROWFORMAT, SLPSBLOROWFORMAT	Formatting string for creation of names for SLP lower step bound rows [ Logging, SLP]
XSLP_SBNAME, SLPSBNAME	Name of the set of initial step bounds to be used [ Logging, SLP]
XSLP_SBROWOFFSET, SLPSBROWOFFSET	Position of first character of SLP variable name used to create name of SLP lower and upper step bound rows [ Logging, SLP]
XSLP_SBSTART, SLPSBSTART	SLP iteration after which step bounds are first applied [ SLP]
XSLP_SBUPROWFORMAT, SLPSBUPROWFORMAT	Formatting string for creation of names for SLP upper step bound rows [ Logging, SLP]
XSLP_SCALE	When to re-scale the SLP problem [ Numerics, SLP]
XSLP_SCALECOUNT	Iteration limit used in determining when to re-scale the SLP matrix [ Numerics, SLP]
XSLP_SHRINK, SLPSHRINK	Multiplier to reduce a step bound [ SLP]
XSLP_SHRINKBIAS, SLPSHRINKBIAS	Defines an overwrite / adjustment of step bounds for improving iterations [ SLP]
XSLP_SLPLOG	Frequency with which SLP status is printed [ Logging, SLP]
XSLP_SOLVER, LOCALSOLVER	Selects the library to use for local solves [ Solution Process]
XSLP_STOL_A, SLPSTOL_A	Absolute slack convergence tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_STOL_R, SLPSTOL_R	Relative slack convergence tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_STOPOUTOFRANGE, NLPSTOPOUTOFRANGE	Stop optimization and return error code if internal function argument is out of range [ SLP]
XSLP_THREADS, NLPTHREADS	Default number of threads to be used [ Parallel]
XSLP_THREADSAFEUSERFUNC, NLPTHREADSAFEUSERFUNC	Defines if user functions are allowed to be called in parallel [ Parallel, User Functions]
XSLP_TOLNAME, SLPTOLNAME	Name of the set of tolerance sets to be used [ File IO, SLP]
XSLP_TRACEMASK, SLPTRACEMASK	Mask of variable or row names that are to be traced through the SLP iterates [ Logging, SLP]
XSLP_TRACEMASKOPS, SLPTRACEMASKOPS	Controls the information printed for XSLP_TRACEMASK. [ Bit-vector, Logging, SLP]
XSLP_UNFINISHEDLIMIT, SLPUNFINISHEDLIMIT	The number of consecutive SLP iterations that may have an unfinished status before the solve is terminated. [ Linearizations, SLP]
XSLP_UPDATEFORMAT, SLPUPDATEFORMAT	Formatting string for creation of names for SLP update rows [ Logging, SLP]
XSLP_UPDATEOFFSET, SLPUPDATEOFFSET	Position of first character of SLP variable name used to create name of SLP update row [ Logging, SLP]
XSLP_VALIDATIONFACTOR, NLPVALIDATIONFACTOR	Minimum improvement in validation targets to continue iterating [ SLP, SLP-convergence, Tolerances]
XSLP_VALIDATIONTARGET_K, NLPVALIDATIONTARGET_K	Optimality target tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_VALIDATIONTARGET_R, NLPVALIDATIONTARGET_R	Feasiblity target tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_VALIDATIONTOL_A, NLPVALIDATIONTOL_A	Absolute tolerance for the XSLPvalidate procedure [ SLP, Tolerances]
XSLP_VALIDATIONTOL_K, NLPVALIDATIONTOL_K	Relative tolerance for the XSLPvalidatekkt procedure [ SLP, Tolerances]
XSLP_VALIDATIONTOL_R, NLPVALIDATIONTOL_R	Relative tolerance for the XSLPvalidate procedure [ Tolerances]
XSLP_VCOUNT, SLPVCOUNT	Number of SLP iterations over which to measure static objective (3) convergence [ SLP, SLP-convergence]
XSLP_VLIMIT, SLPVLIMIT	Number of SLP iterations after which static objective (3) convergence testing starts [ SLP, SLP-convergence]
XSLP_VTOL_A, SLPVTOL_A	Absolute static objective (3) convergence tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_VTOL_R, SLPVTOL_R	Relative static objective (3) convergence tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_WCOUNT, SLPWCOUNT	Number of SLP iterations over which to measure the objective for the extended convergence continuation criterion [ SLP, SLP-convergence]
XSLP_WTOL_A, SLPWTOL_A	Absolute extended convergence continuation tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_WTOL_R, SLPWTOL_R	Relative extended convergence continuation tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_XCOUNT, SLPXCOUNT	Number of SLP iterations over which to measure static objective (1) convergence [ SLP, SLP-convergence]
XSLP_XLIMIT, SLPXLIMIT	Number of SLP iterations up to which static objective (1) convergence testing is performed [ Limits, SLP, SLP-convergence]
XSLP_XTOL_A, SLPXTOL_A	Absolute static objective function (1) tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_XTOL_R, SLPXTOL_R	Relative static objective function (1) tolerance [ SLP, SLP-convergence, Tolerances]
XSLP_ZERO, NLPZERO	Absolute tolerance [ Tolerances]
XSLP_ZEROCRITERION, SLPZEROCRITERION	Bitmap determining the behavior of the placeholder deletion procedure [ Bit-vector, SLP]
XSLP_ZEROCRITERIONCOUNT, SLPZEROCRITERIONCOUNT	Number of consecutive times a placeholder entry is zero before being considered for deletion [ Limits, SLP]
XSLP_ZEROCRITERIONSTART, SLPZEROCRITERIONSTART	SLP iteration at which criteria for deletion of placeholder entries are first activated. [ SLP]

Knitro controls

All Knitro controls are available with an 'X' pre-tag. For example the Knitro integer control 'KTR_PARAM_ALGORITHM' can be set using XSLPsetintcontrol using the control ID defined as 'XKTR_PARAM_ALGORITHM'. Please refer to the Xpress Knitro manual for the description of the Knitro controls.

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Contents

Index

Glossary

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Control Parameters

Knitro controls