Class IntegerSolver

java.lang.Object

org.ojalgo.optimisation.GenericSolver

org.ojalgo.optimisation.integer.IntegerSolver

All Implemented Interfaces:

Optimisation, Optimisation.Solver

public final class IntegerSolver
extends GenericSolver

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
static final class	IntegerSolver.ModelIntegration
(package private) static final class	IntegerSolver.NodeStatistics	When a node is determined to be a leaf - no further branching - what was the reason?

Nested classes/interfaces inherited from class GenericSolver

GenericSolver.Builder<B,S>

Nested classes/interfaces inherited from interface Optimisation

Optimisation.Constraint, Optimisation.ConstraintType, Optimisation.Integration<M,S>, Optimisation.Model, Optimisation.Objective, Optimisation.Options, Optimisation.ProblemStructure, Optimisation.Result, Optimisation.Sense, Optimisation.Solver, Optimisation.State

Field Summary

Fields

Modifier and Type	Field	Description
static final IntegerSolver.ModelIntegration	INTEGRATION
private Optimisation.Result	myBestResultSoFar
private final MultiviewSet<NodeKey>	myDeferredNodes
private final MultiaryFunction.TwiceDifferentiable<Double>	myFunction
private final ExpressionsBasedModel	myIntegerModel
private final boolean	myMinimisation
private final IntegerSolver.NodeStatistics	myNodeStatistics

Fields inherited from class GenericSolver

options

Constructor Summary

Constructors

Constructor	Description
IntegerSolver(ExpressionsBasedModel model)

Method Summary

Modifier and Type	Method	Description
protected Optimisation.Result	buildResult()
(package private) boolean	compute(NodeKey nodeKey, NodeSolver nodeSolver, CharacterRing.RingLogger nodePrinter, ModelStrategy strategy)
protected double	evaluateFunction(Access1D<?> solution)
protected MatrixStore<Double>	extractSolution()
(package private) static void	flush(CharacterRing.RingLogger buffer, BasicLogger receiver)
protected Optimisation.Result	getBestEstimate()
protected Optimisation.Result	getBestResultSoFar()
(package private) int	identifyNonIntegerVariable(Optimisation.Result nodeResult, NodeKey nodeKey, ModelStrategy strategy)	Should return the index of the (best) integer variable to branch on.
protected boolean	isIterationNecessary()
protected void	logProgress(int iterationsDone, String classSimpleName, CalendarDateDuration duration)
static IntegerSolver	make(ExpressionsBasedModel model)
protected void	markInteger(NodeKey key, Optimisation.Result result, ModelStrategy strategy)
private CharacterRing.RingLogger	newPrinter()
static IntegerSolver	newSolver(ExpressionsBasedModel model)
Optimisation.Result	solve(Optimisation.Result kickStarter)
String	toString()
protected boolean	validate()	Should validate the solver data/input/structue.

Methods inherited from class GenericSolver

countIterations, countTime, error, getClassSimpleName, getDuration, getState, incrementIterationsCount, isIterationAllowed, isLogDebug, isLogOff, isLogProgress, log, log, log, log, printf, resetIterationsCount, setState, setValidator, validate, validate

Methods inherited from class Object

clone, equals, finalize, getClass, hashCode, notify, notifyAll, wait, wait, wait

Methods inherited from interface Optimisation.Solver

dispose, solve

Field Details

INTEGRATION

public static final IntegerSolver.ModelIntegration INTEGRATION

myBestResultSoFar

private volatile Optimisation.Result myBestResultSoFar

myDeferredNodes

private final MultiviewSet<NodeKey> myDeferredNodes

myFunction

private final MultiaryFunction.TwiceDifferentiable<Double> myFunction

myIntegerModel

private final ExpressionsBasedModel myIntegerModel

myMinimisation

private final boolean myMinimisation

myNodeStatistics

private final IntegerSolver.NodeStatistics myNodeStatistics

Constructor Details

IntegerSolver

IntegerSolver(ExpressionsBasedModel model)

Method Details

make

public static IntegerSolver make(ExpressionsBasedModel model)

newSolver

public static IntegerSolver newSolver(ExpressionsBasedModel model)

flush

static void flush(CharacterRing.RingLogger buffer,
 BasicLogger receiver)

solve

public Optimisation.Result solve(Optimisation.Result kickStarter)

toString

public String toString()

Overrides:

toString in class Object

newPrinter

private CharacterRing.RingLogger newPrinter()

buildResult

protected Optimisation.Result buildResult()

evaluateFunction

protected double evaluateFunction(Access1D<?> solution)

extractSolution

protected MatrixStore<Double> extractSolution()

getBestEstimate

protected Optimisation.Result getBestEstimate()

getBestResultSoFar

protected Optimisation.Result getBestResultSoFar()

isIterationNecessary

protected boolean isIterationNecessary()

logProgress

protected void logProgress(int iterationsDone,
 String classSimpleName,
 CalendarDateDuration duration)

Overrides:

logProgress in class GenericSolver

markInteger

protected void markInteger(NodeKey key,
 Optimisation.Result result,
 ModelStrategy strategy)

validate

protected boolean validate()

Should validate the solver data/input/structue. Even "expensive" validation can be performed as the method should only be called if Optimisation.Options.validate is set to true. In addition to returning true or false the implementation should set the state to either Optimisation.State.VALID or Optimisation.State.INVALID (or possibly Optimisation.State.FAILED). Typically the method should be called at the very beginning of the solve-method.

Returns:

Is the solver instance valid?

compute

boolean compute(NodeKey nodeKey,
 NodeSolver nodeSolver,
 CharacterRing.RingLogger nodePrinter,
 ModelStrategy strategy)

identifyNonIntegerVariable

int identifyNonIntegerVariable(Optimisation.Result nodeResult,
 NodeKey nodeKey,
 ModelStrategy strategy)

Should return the index of the (best) integer variable to branch on. Returning a negative index means an integer solution has been found (no further branching). Does NOT return a global variable index - it's the index among the integer variable.