XPRSconstants

Number of outstanding nodes.

Constant used in enumeration 'DEFAULTALG'

Constant used in enumeration 'DEFAULTALG'

Constant used in enumeration 'CHOLESKYALG'

The algorithm to be used for the final clean up step after the crossover.

The algorithm the optimizer currently is running / was running just before completition.

Constant used in enumeration 'enum_allow_compute'

Controls aggressiveness of searching for alternative reduced cost

Constant used in enumeration 'ALWAYSNEVERAUTOMATIC'

A measure between 0 and 1 for how numerically unstable the problem is.

Simplex: This indicates whether automatic perturbation is performed.

The amount of heap memory detected by Xpress as free.

Select which tasks to run in background jobs (for example in parallel to the root cut loop).

Constant used in enumeration 'BACKTRACKALG'

Constant used in enumeration 'BACKTRACKALG'

Constant used in enumeration 'BACKTRACKALG'

Constant used in enumeration 'BACKTRACKALG'

Constant used in enumeration 'BACKTRACKALG'

Branch and Bound: Specifies how to break ties when selecting the next node to work on when a full backtrack is performed.

Constant used in enumeration 'BARORDER'

Constant used in enumeration 'BARORDER'

This control determines which barrier algorithm is used to solve the problem.

Absolute condition measure calculated in the last iteration of the barrier algorithm.

If set to a positive integer it determines the number of physical CPU cores assumed to be present in the system by the barrier and hybrid gradient algorithms.

Indicates whether or not the basis crossover phase has been entered.

Sum of the dual infeasibilities for the Newton barrier algorithm.

Newton barrier and hybrid gradient: This is a convergence parameter, representing the tolerance for dual infeasibilities.

Defines how the barrier algorithm scales free variables.

Newton barrier: The target tolerance for the relative duality gap.

The maximum number of restarts in the hybrid gradient algorithm.

Constant used in enumeration 'BARHGOPS'

Constant used in enumeration 'BARHGOPS'

Constant used in enumeration 'BARHGOPS'

Constant used in enumeration 'BARHGOPS'

Number of Newton barrier iterations.

Threshold for the barrier to handle large bounds.

Defines how the barrier scales the objective.

If set to a positive integer it determines the number of concurrent threads for the sparse matrix ordering algorithm in the Newton-barrier method.

Newton barrier: In numerically challenging cases it is often advantageous to apply perturbations on the KKT system to improve its numerical properties.

Constant used in enumeration 'BARPRESOLVEOPS'

Sum of the primal infeasibilities for the Newton barrier algorithm.

Newton barrier and hybrid gradient: This is a convergence parameter, indicating the tolerance for primal infeasibilities.

This control determines how the barrier algorithm applies regularization on the KKT system.

Number of linearly dependent binding constraints at the optimal barrier solution.

This determines whether the barrier has to decide which is the best solution found or return the solution computed by the last barrier iteration.

Newton barrier: This sets a weight for the warm-start point when warm-start is set for the barrier algorithm.

If set to a positive integer it determines the number of threads implemented to run the Newton-barrier and hybrid gradient algorithms.

The infeasibility penalty used if the "Big M" method is implemented.

Constant used in enumeration 'ONOFF'

Active bound name.

Constant used in enumeration 'BRANCHCHOICE'

Branch and Bound: Determines whether the optimizer should attempt to branch on general split disjunctions during the branch and bound search.

The value of the branching variable at a node of the Branch and Bound tree.

The number of nodes to include in the best-first search before switching to the local first search ( NODESELECTION = 4).

Minimum delay in milliseconds between two consecutive executions of the CHECKTIME callback in the same solution process

This attribute counts the number of times the optimal node callback set by XPRSaddcboptnode has been called for the current node, including the current callback call.

Check input arrays for bad data.

This attribute is used to set the value of the MAXCHECKSONMAXTIME control.

Newton barrier: The tolerance for pivot elements in the Cholesky decomposition of the normal equations coefficient matrix, computed at each iteration of the barrier algorithm.

Constant used in enumeration 'CLAMPING'

Constant used in enumeration 'CLAMPING'

Number of columns (i.e.

Selects the Insight execution service that will be used for solving remote optimizations.

Selects the priority that will be used for remote optimization jobs.

Constant used in enumeration 'enum_compute_log'

Constant used in enumeration 'enum_compute_log'

Determines the number of threads used by the concurrent solver.

Number of second order and rotated second order cones in the problem.

Number of logical cores detected by the optimizer, which is the total number of threads the hardware can execute across all CPUs.

Number of logical cores per CPU unit detected by the optimizer, which is the number of threads each CPU can execute.

decay term for confined primal integral computation.

Newton Barrier: Selects the AMD, Intel x86 or ARM vectorization instruction set that Barrier should run optimized code for.

How time should be measured when timings are reported in the log and when checking against time limits

Newton barrier and hybrid gradient: This control determines whether the barrier method will cross over to the simplex method when at optimal solution has been found, to provide an end basis (see XPRSgetbasis, XPRSwritebasis) and advanced sensitivity analysis information (see XPRSobjsa, XPRSrhssa, XPRSbndsa).

Number of simplex iterations performed in crossover.

Newton barrier and hybrid gradient: a bit vector for adjusting the behavior of the crossover procedure.

The amount of dynamically allocated heap memory by the problem being solved.

The current MIP cut off.

Limit on the number of cuts and cut coefficients the optimizer is allowed to add to the matrix during tree search.

Number of cuts being added to the matrix.

Constant used in enumeration 'CUTSELECT'

Constant used in enumeration 'CUTSELECT'

Constant used in enumeration 'CUTSELECT'

Constant used in enumeration 'CUTSELECT'

Constant used in enumeration 'CUTSELECT'

Constant used in enumeration 'CUTSTRATEGY'

Constant used in enumeration 'CUTSTRATEGY'

Constant used in enumeration 'CUTSTRATEGY'

Newton barrier: Columns with more than DENSECOLLIMIT elements are considered to be dense.

Constant used in enumeration 'DUALGRADIENT'

Constant used in enumeration 'DUALGRADIENT'

For a linear problem or the initial linear relaxation of a MIP, determines whether to form and solve the dual problem.

Constant used in enumeration 'DUALIZEOPS'

This bit-vector control specifies the dual simplex strategy.

Constant used in enumeration 'DUALSTRATEGY'

Number of matrix nonzeros (elements).

The Markowitz tolerance for the elimination phase of the presolve.

If characters illegal to an mps or lp file should be escaped to guarantee readability, and whether escaped characters should be transformed back when reading such a file.

The initial number of extra columns to allow for in the matrix.

The initial number of extra MIP entities to allow for.

The initial number of extra elements in sets to allow for in the matrix.

MIP: Decides if the Feasibility Jump heuristic should be run.

Constant used in enumeration 'FEASIBILITYPUMP'

Constant used in enumeration 'FEASIBILITYPUMP'

This tolerance determines when a solution is treated as feasible.

This specifies the target feasibility tolerance for the solution refiner.

Dual simplex: specifies whether the dual simplex solver should always use the parallel simplex algorithm.

The number of general constraints (i.e.

Constant used in enumeration 'GENCONSTYPE'

Constant used in enumeration 'GENCONSTYPE'

This control specifies the reformulation method for absolute value general constraints at the beginning of the search.

Number of constant values in general constraints (MIN/MAX constraints) in the problem.

Constant used in enumeration 'GLOBALBOUNDINGBOX'

Constant used in enumeration 'GLOBALBOUNDINGBOX'

When integer-feasible (for MINLP, any solution for NLP) but nonlinear-infeasible solutions are encountered within a global solve, the integer variables can be fixed and a local solver (as defined by the LOCALSOLVER control) can be called on the remaining continuous problem.

Constant used in enumeration 'GLOBALLSHEURSTRATEGY'

Constant used in enumeration 'GLOBALLSHEURSTRATEGY'

Limit on the number of rounds of outer approximation and convexification cuts generated for the root node, when solving an (MI)NLP to global optimality.

Specifies the maximum number of tangent cuts when setting up the initial relaxation during a global solve.

Whether spatial branchings on original variables should be preferred over branching on auxiliary variables that were introduced by the reformulation of the global solver.

Limit on the number of rounds of outer approximation and convexification cuts generated for each node in the tree, when solving an (MI)NLP to global optimality.

Branch and Bound: Determines whether primal heuristics should be run before the initial LP relaxation has been solved.

Branch and Bound: Simplex iteration limit for reoptimizing during the diving heuristic.

Branch and Bound: Enables a more cautious strategy for the diving heuristic, where it tries to push binaries and integer variables to their bounds using the objective, instead of directly fixing them.

Branch and Bound: Chooses the strategy for the diving heuristic.

Branch and Bound: This specifies whether local search heuristics without objective or with an auxiliary objective should always be used, despite the automatic selection of the Optimiezr.

Branch and Bound: This specifies the maximum number of heuristic solutions that will be found in the tree search.

Constant used in enumeration 'HEURSEARCHSELECT'

Constant used in enumeration 'HEURSEARCHSELECT'

Select how user-set controls should affect local search heuristics.

Branch and Bound: This specifies how often the local search heuristic should be run in the tree.

A bit vector control for selecting which local search heuristics to apply on the root node of a MIP solve.

A bit vector control for selecting which local search heuristics to apply during the tree search of a MIP solve.

Determines whether the Shift-and-propagate primal heuristic should be executed.

Deprecated.

Deprecated.

Branch and Bound: The number of threads to dedicate to running heuristics during the root solve.

Determines if the convexity of the problem is checked before optimization.

Deprecated.

Constant used in enumeration 'IISSOLSTATUS'

Constant used in enumeration 'IISSOLSTATUS'

Selects which part of the restrictions (bounds, constraints, entities) should always be kept in an IIS.

Constant used in enumeration 'IISOPS'

Constant used in enumeration 'IISOPS'

Constant used in enumeration 'IISOPS'

Constant used in enumeration 'IISOPS'

Constant used in enumeration 'IISOPS'

Constant used in enumeration 'IISOPS'

Constant used in enumeration 'IISOPS'

Number of indicator constrains in the problem.

During presolve, indicator constraints will be linearized using a BigM coefficient whenever that BigM coefficient is small enough.

Number of rows (i.e.

Simplex: The frequency with which the basis will be inverted.

The maximum number of seconds to wait for an I/O operation before it is cancelled.

Bit field flag 'IsUserSolution' for MipSolPool Solution

Simplex: This determines whether the basis should be kept when reoptimizing a problem.

Indicates which algorithm to use to solve the problem

Specifies whether special emphasis is placed on getting and staying feasible in the interior-point algorithms.

Specifies the initial value for the barrier parameter : mu used with the barrier algorithms.

Indicates the maximum allowable number of backtracks during the linesearch of the Interior/Direct algorithm before reverting to a CG step.

Indicates the maximum number of refactorizations of the KKT system per iteration of the Interior/Direct algorithm before reverting to a CG step.

Indicates whether a penalty approach is applied to the constraints.

Control of type Integer.

Control of type Integer.

Specifies the initial trust region radius scaling factor used to determine the initial trust region size.

Specifies the final absolute stopping tolerance for the feasibility error.

Specifies how to compute the (approximate) Hessian of the Lagrangian.

Specifies the (relative) tolerance used for declaring infeasibility of a model.

Specifies the number of limited memory pairs stored when approximating the Hessian using the limited-memory quasi-Newton BFGS option.

Specifies the number of limited memory pairs stored when approximating the Hessian using the limited-memory quasi-Newton BFGS option.

Specifies which branching rule to use for MIP branch and bound procedure.

Specifies whether or not to branch on generalized upper bounds (GUBs).

Specifies which MIP heuristic search approach to apply to try to find an initial integer feasible point.

The absolute integrality gap stop tolerance for MIP.

Specifies rules for adding MIP knapsack cuts.

Specifies the maximum number of nodes explored.

Specifies node printing interval for XKTR_PARAM_MIP_OUTLEVEL when XKTR_PARAM_MIP_OUTLEVEL > 0.

Specifies the method used to initialize pseudo-costs corresponding to variables that have not yet been branched on in the MIP method.

Specifies the MIP rounding rule to apply.

Specifies the maximum number of candidates to explore for MIP strong branching.

Specifies the maximum number of iterations to allow for MIP strong branching solves.

Control of type Integer.

Control of type Double.

Control of type Double.

Control of type Integer.

Specifies the extreme limits of the objective function for purposes of determining unboundedness.

Specifies the final absolute stopping tolerance for the KKT (optimality) error.

Control of type Integer.

Determine whether or not to use the Knitro presolver to try to simplify the model by removing variables or constraints.

Performs a scaling of the objective and constraint functions based on their values at the initial point.

The optimization process will terminate if the relative change in all components of the solution point estimate is less than xtol.

Number of infeasible MIP entities to create lift-and-project cuts for during each round of Gomory cuts at the top node (see GOMCUTS).

Control of type Integer.

Constant used in enumeration 'LPSTATUS'

Constant used in enumeration 'LPSTATUS'

Constant used in enumeration 'LPSTATUS'

Constant used in enumeration 'LPSTATUS'

Constant used in enumeration 'LPSTATUS'

Constant used in enumeration 'LPFLAGS'

Constant used in enumeration 'LPFLAGS'

Simplex and barrier: whether to fold an LP problem before solving it.

Simplex: The frequency at which the simplex log is printed.

Simplex: The style of the simplex log.

This specifies the simplex iteration limit the solution refiner can spend in attempting to increase the accuracy of an LP solution.

The matrix name.

Maximum calculated absolute dual infeasibility in the unscaled original problem.

This control is intended for use where optimization runs that are terminated using the MAXCUTTIME control are required to be reproduced exactly.

The maximum amount of time allowed for generation of cutting planes and reoptimization.

Presolve: When tighter bounds are calculated during MIP preprocessing, only bounds whose absolute value are smaller than MAXIMPLIEDBOUND will be applied to the problem.

Largest basis condition number (also known as kappa) calculated through all nodes sampled by MIPKAPPAFREQ.

The maximum number of matrix coefficients to buffer before flushing into the internal representation of the problem.

When RESOURCESTRATEGY is enabled, this control sets the maximum amount of memory in megabytes the optimizer targets to allocate.

Maximum integer fractionality in the solution.

Branch-and-Bound: The maximum number of tasks to run in parallel during a MIP solve.

Number of lines between page breaks in printable output.

Maximum calculated relative dual infeasibility in the unscaled original problem.

This determines the maximum scaling factor that can be applied during scaling.

Deprecated.

Level of Multi-Commodity Flow (MCF) cutting planes separation: This specifies how much aggresively MCF cuts should be separated.

Constant used in enumeration 'MIPSTATUS'

Constant used in enumeration 'MIPSTATUS'

Constant used in enumeration 'MIPSTATUS'

Constant used in enumeration 'MIPSTATUS'

Branch and bound: if the gapnotify callback has been set using XPRSaddcbgapnotify, then this callback will be triggered during the tree search when the absolute gap reaches or passes the value you set of the MIPRELGAPNOTIFY control.

Branch and bound: if the gapnotify callback has been set using XPRSaddcbgapnotify, then this callback will be triggered during the tree search when the best solution value reaches or passes the value you set of the MIPRELGAPNOTIFYOBJ control.

Branch and Bound: The amount to add to the objective function of the best integer solution found to give the new CURRMIPCUTOFF.

Determines whether disconnected components in a MIP should be solved as separate MIPs.

Selects the number of concurrent solves to start for a MIP.

Number of MIP entities (i.e.

Number of integer infeasibilities, including violations of special ordered sets, at the current node.

MIP log print control.

Branch and Bound: Type of integer processing to be performed.

Constant used in enumeration 'MIPPRESOLVE'

Constant used in enumeration 'MIPPRESOLVE'

Constant used in enumeration 'MIPPRESOLVE'

Constant used in enumeration 'MIPPRESOLVE'

This defines an effort limit expressed as simplex iterations for the MIP solution refiner.

Branch and bound: if the gapnotify callback has been set using XPRSaddcbgapnotify, then this callback will be triggered during the branch and bound tree search when the relative gap reaches or passes the value you set of the MIPRELGAPNOTIFY control.

Branch and Bound: controls strategy for in-tree restarts.

Constant used in enumeration 'MIPRESTART'

Constant used in enumeration 'MIPRESTART'

Number of integer solutions that have been found.

(MIP) solution status.

The ID for the MIP thread.

Branch and Bound: This is the tolerance within which a decision variable's value is considered to be integral.

This control determines which algorithm is to be used to solve mixed integer quadratic constrained and mixed integer second order cone problems.

When reading an MPS file, this control determines which entries from the BOUNDS section will be read.

Specifies the format of MPS files.

When reading an MPS file, this control determines which neutral row will be read as the objective function.

When reading an MPS file, this control determines which entries from the RHS section will be read.

Control of type Integer.

Attribute of type Double.

Attribute of type Integer.

Control of type Integer.

Control of type Double.

Defines the maximum range inside which initial points are generated by multistart presets

Control of type Double.

Control of type Integer.

Control of type Integer.

Attribute of type Integer.

Control of type Integer.

Control of type Double.

Attribute of type Integer.

Attribute of type Integer.

Attribute of type Integer.

Attribute of type Double.

Attribute of type Double.

Control of type Integer.

Log level for multi-objective optimization.

Constant used in enumeration 'MULTIOBJOPS'

Constant used in enumeration 'MULTIOBJOPS'

The level of logging during the multistart run.

The maximum total time to be spent in the mutlistart search.

Random seed used for the automatic generation of initial point when loading multistart presets

Branch and Bound: This determines whether the callback routines are mutexed from within the optimizer.

The length (in 8 character units) of row and column names in the matrix.

Constant used in enumeration 'NAMESPACES'

Constant used in enumeration 'NAMESPACES'

Constant used in enumeration 'NAMESPACES'

Constant used in enumeration 'NAMESPACES'

Constant used in enumeration 'NAMESPACES'

Limit the number of degenerate pivots of the network simplex algorithm, before switching to either primal or dual simplex, depending on ALGAFTERNETWORK.

Default initial value for an SLP variable if none is explicitly given

Determines if the parallel features of SLP should be guaranteed to be deterministic

Evaluation strategy for user functions

Second order differentiation mode when using analytical derivatives

Number of SLP variables appearing only in coefficients

Unique identifier for the current job

Use linear and quadratic constraints and objective function to further reduce bounds on all variables

The maximum time in seconds that the SLP optimization will run before it terminates

Number of model columns in the problem

Time spent in optimization

Number of model rows in the extended original problem

This control determines whether presolving should be performed prior to starting the main algorithm

Bitmap indicating the SLP presolve actions to be taken

Minimum absolute value for a variable which is identified as nonzero during SLP presolve

Reference solution value to take into account when calculating the primal integral

Selects the library to use for local solves

Bitmap holding the problem convergence status

Status of the optimization process.

Defines if user functions are allowed to be called in parallel

Number of user functions

Number of calls made to user functions

Absolute validation index

Relative validation index

Feasiblity target tolerance

Relative tolerance for the XSLPvalidatekkt procedure

Number of SLP variables

Depth of the current node.

Number of nodes solved so far in the MIP search.

Constant used in enumeration 'NODESELECTION'

Constant used in enumeration 'NODESELECTION'

Constant used in enumeration 'NODESELECTION'

How much emphasis to place on numerical stability instead of solve speed.

Constant used in enumeration 'enum_obj_sense'

Constant used in enumeration 'OBJCONTROL'

Constant used in enumeration 'OBJCONTROL'

Constant used in enumeration 'OBJCONTROL'

Deprecated.

Custom objective scaling factor, expressed as a power of 2.

Number of objectives that will be solved during the current multi-objective solve.

Value of the (observed) primal integral.

This specifies the target optimality tolerance for the solution refiner.

Constant used in enumeration 'OPTIMIZETYPE'

Constant used in enumeration 'OPTIMIZETYPE'

The type of solver used in the last call to XPRSoptimize, XPRSmipoptimize, XPRSlpoptimize or XPRSnlpoptimize.

Number of input variables in general constraints in the original problem before presolving.

Number of constant values in general constraints in the original problem before presolving.

Number of MIP entities (i.e.

Number of piecewise linear constraints in the original problem before presolving.

Number of rows with quadratic coefficients in the original matrix before presolving.

Number of rows (i.e.

Number of special ordered sets in the original matrix before presolving.

This controls the level of output produced by the Optimizer during optimization.

Constant used in enumeration 'OUTPUTLOG'

Constant used in enumeration 'OUTPUTLOG'

Zero tolerance on print values.

An estimate of the peak amount of dynamically allocated heap memory by the problem.

Minimum absolute penalty variable coefficient.

The total number of physical cores across all CPUs detected by the optimizer.

Simplex: The zero tolerance for matrix elements.

The partial pricing candidate list sizing parameter.

Determines if a lattice basis reduction algorithm should be attempted as part of presolve

Determines if convex quadratic constraints should be used for inferring bound reductions on variables when solving a MIP.

Presolve: Specifies whether the optimizer should attempt to recombine constraints in order to reduce the number of non zero coefficients when presolving a mixed integer problem.

Constant used in enumeration 'PRECOEFELIM'

Presolve: determines whether small independent components should be detected and solved as individual subproblems during root node processing.

Presolve: decompose regular and rotated cones with more than two elements and apply Outer Approximation on the resulting components.

Presolve: convert a linear or quadratic objective function into an objective transfer constraint

A measure between 0 and 1 to predict how numerically unstable the current MIP solve can be expected to be.

Constant used in enumeration 'PREDOMCOL'

Constant used in enumeration 'PREDOMCOL'

Presolve: Determines the level of dominated row removal reductions to perform when presolving a problem.

Constant used in enumeration 'PREDOMROW'

Constant used in enumeration 'PREDOMROW'

Presolve: Determines the type of duplicate rows to look for and eliminate when presolving a problem.

Presolve: Determines if a folding procedure should be used to aggregate continuous columns in an equitable partition.

Presolve: Determines whether to check for and remove linearly dependent equality constraints when presolving a problem.

This bit vector control specifies whether to randomly permute rows, columns and MIP entities when starting the presolve.

Presolve: Amount of probing to perform on binary variables during presolve.

Constant used in enumeration 'PREPROBING'

Constant used in enumeration 'PREPROBING'

Presolve: specifies whether the presolver should protect a given dual solution by maintaining the same level of dual feasibility.

Constant used in enumeration 'PRESOLVE'

Constant used in enumeration 'PRESOLVE'

Presolve: The row or column index on which presolve detected a problem to be infeasible or unbounded.

This bit vector control specifies the operations which are performed during the presolve.

Constant used in enumeration 'PRESOLVEOPS'

Constant used in enumeration 'PRESOLVEOPS'

Constant used in enumeration 'PRESOLVEOPS'

Constant used in enumeration 'PRESOLVEOPS'

Constant used in enumeration 'PRESOLVEOPS'

Constant used in enumeration 'PRESOLVEOPS'

Constant used in enumeration 'PRESOLVEOPS'

Constant used in enumeration 'PRESOLVEOPS'

Constant used in enumeration 'PRESOLVEOPS'

Constant used in enumeration 'PRESOLVEOPS'

Problem status as a bit map.

Constant used in enumeration 'PRESOLVESTATE'

Constant used in enumeration 'PRESOLVESTATE'

Constant used in enumeration 'PRICING'

Constant used in enumeration 'PRICING'