Namespace OPTANO.Modeling.Optimization.Solver.FicoXpress804.ConfigurationEnums

Enums

BranchDisjunctions

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

Specifies how cautious or aggressive the optimizer should be when searching for and applying conflict cuts. Conflict cuts are in-tree cuts derived from nodes found to be infeasible or cut off, which can be used to cut off other branches of the search tree.

Refers to: http://www.maths.ed.ac.uk/hall/Xpress/FICO_Docs/optimizer/HTML/CONFLICTCUTS.html

CutSelects

A flags enum providing detailed control of the cuts created for the root node of a global solve. Use TREECUTSELECT to control cuts during the tree search.

Refers to: http://www.maths.ed.ac.uk/hall/Xpress/FICO_Docs/optimizer/HTML/CUTSELECT.html

CutStrategy

The cut strategy. Used to specify the cut intensity during tree search. WARNING: Make sure to not accidentally select the default-value of this enum, which is NoCuts/0, instead of the defined default value of FICO, which is Automatic/-1.

DualGradientPrcing

This specifies the dual simplex pricing method. Refers to: http://www.maths.ed.ac.uk/hall/Xpress/FICO_Docs/optimizer/HTML/DUALGRADIENT.html

HeuristicDiveSpeedUp

Enum to change the emphasis of the diving heuristic from solution quality to diving speed.

HeuristicSearchRootSelections

Enum for selecting which local search heuristics to apply on the root node of a global solve. Use HeuristicSearchTreeSelections to control local search heuristics during the tree search. Default: LargeNeighborhood | SearchUserAddedSolutions (= 17).

The local search heuristics will benefit from having an existing incumbent solution, but it is not required. An initial solution can also be provided by the user through either XPRSloadmipsol or XPRSreadbinsol. Refers to: http://www.maths.ed.ac.uk/hall/Xpress/FICO_Docs/optimizer/HTML/HEURSEARCHROOTSELECT.html

HeuristicSearchTreeSelections

Enum for selecting which local search heuristics to apply on the root node of a global solve. Use HeuristicSearchRootSelections to control local search heuristics on the root node Default: SmallNeighborhoodContinuous (= 1).

HeuristicStrategy

This specifies the heuristic strategy. On some problems it is worth trying more comprehensive heuristic strategies by setting HeuristicStrategy to Enhanced or Extensive. Refers to: http://www.maths.ed.ac.uk/hall/Xpress/FICO_Docs/optimizer/HTML/HEURSTRATEGY.html

HistoryCosts

How to update the pseudo cost for a global entity when a strong branch or a regular branch is applied.

LocalChoice

Controls when to perform a local backtrack between the two child nodes during a dive in the branch and bound tree.

Refers to: http://www.maths.ed.ac.uk/hall/Xpress/FICO_Docs/optimizer/HTML/LOCALCHOICE.html

MipFractionReduce

Specifies how often the optimizer should run a heuristic to reduce the number of fractional integer variables in the node LP solutions.

This heuristic is only applicable to problems that are dual degenerate. These are problems that contain multiple solutions with identical objective function value. The more dual degenerate a problem is, the more likely it will be for this heuristic to have an improving effect. Refers to: http://www.maths.ed.ac.uk/hall/Xpress/FICO_Docs/optimizer/HTML/MIPFRACREDUCE.html

MipPresolves

Type of integer processing to be performed.

PreCoefElim

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.

PreProbing

Amount of probing to perform on binary variables during presolve. This is done by fixing a binary to each of its values in turn and analyzing the implications.

PresolveMode

Enum to control presolve modes at the beginning of the solution process.

RootPresolve

Determines if presolving should be performed on the problem after the global search has finished with root cutting and heuristics.

Scalings

This determines how the Optimizer will rescale a model internally before optimization. If set to 0, no scaling will take place. NOTE: Setting SCALING to 0 will preserve the current scaling of the problem. Refer to: http://www.maths.ed.ac.uk/hall/Xpress/FICO_Docs/optimizer/HTML/SCALING.html