Module ojalgo

Package org.ojalgo.optimisation.linear

Class SimplexTableau

java.lang.Object

org.ojalgo.optimisation.linear.SimplexStore

org.ojalgo.optimisation.linear.SimplexTableau

All Implemented Interfaces:

Access1D<java.lang.Double>, Access2D<java.lang.Double>, Mutate1D, Mutate2D, Structure1D, Structure2D

Direct Known Subclasses:

DenseTableau, SparseTableau

abstract class SimplexTableau
extends SimplexStore
implements Access2D<java.lang.Double>, Mutate2D

Nested Class Summary

Nested classes/interfaces inherited from class org.ojalgo.optimisation.linear.SimplexStore

SimplexStore.ColumnState

Nested classes/interfaces inherited from interface org.ojalgo.structure.Access2D

Access2D.Aggregatable<N extends java.lang.Comparable<N>>, Access2D.Collectable<N extends java.lang.Comparable<N>,R extends Mutate2D>, Access2D.ColumnView<N extends java.lang.Comparable<N>>, Access2D.ElementView<N extends java.lang.Comparable<N>>, Access2D.RowView<N extends java.lang.Comparable<N>>, Access2D.SelectionView<N extends java.lang.Comparable<N>>, Access2D.Sliceable<N extends java.lang.Comparable<N>>, Access2D.Visitable<N extends java.lang.Comparable<N>>

Nested classes/interfaces inherited from interface org.ojalgo.structure.Mutate1D

Mutate1D.Sortable

Nested classes/interfaces inherited from interface org.ojalgo.structure.Mutate2D

Mutate2D.Exchangeable, Mutate2D.Fillable<N extends java.lang.Comparable<N>>, Mutate2D.Mixable<N extends java.lang.Comparable<N>>, Mutate2D.Modifiable<N extends java.lang.Comparable<N>>, Mutate2D.ModifiableReceiver<N extends java.lang.Comparable<N>>, Mutate2D.Receiver<N extends java.lang.Comparable<N>>

Nested classes/interfaces inherited from interface org.ojalgo.structure.Structure1D

Structure1D.BasicMapper<T>, Structure1D.IndexMapper<T>, Structure1D.IntIndex, Structure1D.Logical<S extends Structure1D,B extends Structure1D.Logical<S,B>>, Structure1D.LongIndex, Structure1D.LoopCallback

Nested classes/interfaces inherited from interface org.ojalgo.structure.Structure2D

Structure2D.IntRowColumn, Structure2D.Logical<S extends Structure2D,B extends Structure2D.Logical<S,B>>, Structure2D.LongRowColumn, Structure2D.ReducibleTo1D<R extends Structure1D>, Structure2D.Reshapable, Structure2D.RowColumnKey<R,C>, Structure2D.RowColumnMapper<R,C>

Field Summary

Fields

Modifier and Type	Field	Description
private Primitive2D	myConstraintsBody
private Primitive1D	myConstraintsRHS
private Primitive1D	myObjective
(package private) static NumberContext	PRECISION	Used when pivoting to identify rows with elements that are already very close to zero (to avoid updating those rows).

Fields inherited from class org.ojalgo.optimisation.linear.SimplexStore

edgeWeights, excluded, included, m, n, structure

Constructor Summary

Constructors

Constructor	Description
SimplexTableau(LinearStructure linearStructure)

Method Summary

Modifier and Type	Method	Description
(package private) void	calculateDualDirection(SimplexSolver.ExitInfo exit)
(package private) void	calculateIteration(SimplexSolver.IterDescr iteration, double shift)
(package private) void	calculatePrimalDirection(SimplexSolver.EnterInfo enter)
(package private) Primitive2D	constraintsBody()	The area of the tableau corresponding to the constraints' body.
(package private) Primitive1D	constraintsRHS()	The area of the tableau corresponding to the constraints' RHS.
protected abstract void	doPivot(int row, int col)	Perform the pivot operation on the tableau – only.
(package private) int	findNextPivotColumn(Access1D<java.lang.Double> auxiliaryRow, Access1D<java.lang.Double> objectiveRow)
(package private) abstract boolean	fixVariable(int index, double value)
(package private) java.util.Collection<Equation>	generateCutCandidates(boolean[] integer, NumberContext accuracy, double fractionality)	Simplified version of SimplexStore.generateCutCandidates(boolean[], NumberContext, double, double[]) for specific use with SimplexTableauSolver.
java.lang.Double	get(long row, long col)
(package private) double	getCost(int j)
(package private) double	getCurrentElement(int i, SimplexSolver.EnterInfo enter)	The current (tableau) constraint body element.
(package private) double	getCurrentElement(SimplexSolver.ExitInfo exit, int je)	The current (tableau) constraint body element.
(package private) double	getCurrentRHS(int i)	The current (tableau) constraint RHS.
(package private) abstract double	getInfeasibility()
(package private) double	getInfeasibility(int i)
(package private) abstract double	getValue()
(package private) abstract Primitive2D	newConstraintsBody()
(package private) abstract Primitive1D	newConstraintsRHS()
(package private) abstract Primitive1D	newObjective()
(package private) SimplexTableauSolver	newSimplexTableauSolver(Optimisation.Options optimisationOptions)
(package private) static java.util.function.Function<LinearStructure,SimplexTableau>	newTableauFactory(Optimisation.Options options)
(package private) Primitive1D	objective()	The area of the tableau corresponding to the objective function.
protected void	pivot(SimplexSolver.IterDescr iteration)
protected void	pivot(SimplexTableauSolver.IterationPoint iteration)
(package private) void	prepareToIterate()
(package private) void	resetBasis(int[] newBasis)	Everything that is not in the basis is set to be in at lower bound.
void	set(long row, long col, java.lang.Comparable<?> value)
(package private) void	setupClassicPhase1Objective()
(package private) Primitive1D	sliceBodyColumn(int col)
(package private) Primitive1D	sliceBodyRow(int row)
(package private) Primitive1D	sliceConstraintsRHS()
(package private) Primitive1D	sliceDualVariables()
(package private) Primitive1D	sliceTableauColumn(int col)
(package private) Primitive1D	sliceTableauRow(int row)
java.lang.String	toString()
(package private) void	updateDualEdgeWeights(SimplexSolver.IterDescr iteration)	Update edge weights for basic (included) variables.
(package private) void	updatePrimalEdgeWeights(SimplexSolver.IterDescr iteration)	Update edge weights for non-basic (excluded) variables.
(package private) double	value(boolean phase1)	The current, phase 1 or 2, objective function value

Methods inherited from class org.ojalgo.optimisation.linear.SimplexStore

copyBasicSolution, countRemainingArtificials, extractSolution, extractValue, generateCutCandidates, getColumnState, getLowerBound, getLowerBounds, getLowerGap, getRange, getReducedCost, getUpperBound, getUpperBounds, getUpperGap, isArtificial, isExcluded, isIncluded, isNegated, isPrintable, isRemainingArtificials, lower, newDualSimplexSolver, newPhasedSimplexSolver, newPrimalSimplexSolver, newStoreFactory, phase1, removePhase1, resetEdgeWeights, shiftColumn, unbounded, update, updateBasis, updateRange, upper

Methods inherited from class java.lang.Object

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

Methods inherited from interface org.ojalgo.structure.Access1D

asCollectable1D, asKeyed1D, asList, axpy, dot, select, supplyTo, toList, toRawCopy1D

Methods inherited from interface org.ojalgo.structure.Access2D

asCollectable2D, asKeyed2D, byteValue, byteValue, byteValue, byteValue, columns, columns, columns, doubleValue, doubleValue, doubleValue, doubleValue, elements, floatValue, floatValue, floatValue, floatValue, get, intValue, intValue, intValue, intValue, longValue, longValue, longValue, longValue, nonzeros, rows, rows, rows, select, select, shortValue, shortValue, shortValue, shortValue, toRawCopy2D

Methods inherited from interface org.ojalgo.structure.Mutate1D

reset

Methods inherited from interface org.ojalgo.structure.Mutate2D

set, set, set, set, set, set, set, set, set, set, set, set, set, set, set, set, set, set, set, set, set, set, set, set, set

Methods inherited from interface org.ojalgo.structure.Structure2D

count, countColumns, countRows, firstInColumn, firstInRow, getColDim, getMaxDim, getMinDim, getRowDim, isEmpty, isFat, isScalar, isSquare, isTall, isVector, limitOfColumn, limitOfRow, size

Field Detail

PRECISION

static final NumberContext PRECISION

Used when pivoting to identify rows with elements that are already very close to zero (to avoid updating those rows).

myConstraintsBody

private transient Primitive2D myConstraintsBody

myConstraintsRHS

private transient Primitive1D myConstraintsRHS

myObjective

private transient Primitive1D myObjective

Constructor Detail

SimplexTableau

SimplexTableau(LinearStructure linearStructure)

Method Detail

newTableauFactory

static java.util.function.Function<LinearStructure,SimplexTableau> newTableauFactory(Optimisation.Options options)

get

public final java.lang.Double get(long row,
                                  long col)

Specified by:

get in interface Access2D<java.lang.Double>

set

public final void set(long row,
                      long col,
                      java.lang.Comparable<?> value)

Specified by:

set in interface Mutate2D

toString

public java.lang.String toString()

Overrides:

toString in class SimplexStore

doPivot

protected abstract void doPivot(int row,
                                int col)

Perform the pivot operation on the tableau – only. Various auxiliary bookkeeping should NOT be done here.

pivot

protected final void pivot(SimplexSolver.IterDescr iteration)

Overrides:

pivot in class SimplexStore

pivot

protected final void pivot(SimplexTableauSolver.IterationPoint iteration)

calculateDualDirection

final void calculateDualDirection(SimplexSolver.ExitInfo exit)

Specified by:

calculateDualDirection in class SimplexStore

calculateIteration

void calculateIteration(SimplexSolver.IterDescr iteration,
                        double shift)

Specified by:

calculateIteration in class SimplexStore

calculatePrimalDirection

final void calculatePrimalDirection(SimplexSolver.EnterInfo enter)

Specified by:

calculatePrimalDirection in class SimplexStore

constraintsBody

final Primitive2D constraintsBody()

The area of the tableau corresponding to the constraints' body.

Specified by:

constraintsBody in class SimplexStore

See Also:

SimplexStore.constraintsBody()

constraintsRHS

final Primitive1D constraintsRHS()

The area of the tableau corresponding to the constraints' RHS.

Specified by:

constraintsRHS in class SimplexStore

See Also:

SimplexStore.constraintsRHS()

findNextPivotColumn

final int findNextPivotColumn(Access1D<java.lang.Double> auxiliaryRow,
                              Access1D<java.lang.Double> objectiveRow)

fixVariable

abstract boolean fixVariable(int index,
                             double value)

generateCutCandidates

final java.util.Collection<Equation> generateCutCandidates(boolean[] integer,
                                                           NumberContext accuracy,
                                                           double fractionality)

Simplified version of SimplexStore.generateCutCandidates(boolean[], NumberContext, double, double[]) for specific use with SimplexTableauSolver. SimplexSolver and SimplexTableauSolver can both use SimplexTableau, but they use them differently.

getCost

final double getCost(int j)

Specified by:

getCost in class SimplexStore

getCurrentElement

final double getCurrentElement(SimplexSolver.ExitInfo exit,
                               int je)

Description copied from class: SimplexStore

The current (tableau) constraint body element.

Specified by:

getCurrentElement in class SimplexStore

getCurrentElement

final double getCurrentElement(int i,
                               SimplexSolver.EnterInfo enter)

Description copied from class: SimplexStore

The current (tableau) constraint body element.

Specified by:

getCurrentElement in class SimplexStore

getCurrentRHS

final double getCurrentRHS(int i)

Description copied from class: SimplexStore

The current (tableau) constraint RHS.

Specified by:

getCurrentRHS in class SimplexStore

getInfeasibility

abstract double getInfeasibility()

Returns:

The phase 1 objective function value

getInfeasibility

final double getInfeasibility(int i)

Specified by:

getInfeasibility in class SimplexStore

getValue

abstract double getValue()

Returns:

The (phase 2) objective function value

newConstraintsBody

abstract Primitive2D newConstraintsBody()

newConstraintsRHS

abstract Primitive1D newConstraintsRHS()

newObjective

abstract Primitive1D newObjective()

newSimplexTableauSolver

final SimplexTableauSolver newSimplexTableauSolver(Optimisation.Options optimisationOptions)

objective

final Primitive1D objective()

The area of the tableau corresponding to the objective function.

Specified by:

objective in class SimplexStore

See Also:

SimplexStore.objective()

prepareToIterate

void prepareToIterate()

Specified by:

prepareToIterate in class SimplexStore

resetBasis

final void resetBasis(int[] newBasis)

Description copied from class: SimplexStore

Everything that is not in the basis is set to be in at lower bound.

Overrides:

resetBasis in class SimplexStore

setupClassicPhase1Objective

final void setupClassicPhase1Objective()

Specified by:

setupClassicPhase1Objective in class SimplexStore

sliceBodyColumn

final Primitive1D sliceBodyColumn(int col)

sliceBodyRow

final Primitive1D sliceBodyRow(int row)

Specified by:

sliceBodyRow in class SimplexStore

sliceConstraintsRHS

final Primitive1D sliceConstraintsRHS()

sliceDualVariables

final Primitive1D sliceDualVariables()

Specified by:

sliceDualVariables in class SimplexStore

Returns:

An array of the dual variable values (of the original problem, never phase 1).

sliceTableauColumn

final Primitive1D sliceTableauColumn(int col)

sliceTableauRow

final Primitive1D sliceTableauRow(int row)

updateDualEdgeWeights

void updateDualEdgeWeights(SimplexSolver.IterDescr iteration)

Description copied from class: SimplexStore

Update edge weights for basic (included) variables.

Specified by:

updateDualEdgeWeights in class SimplexStore

updatePrimalEdgeWeights

void updatePrimalEdgeWeights(SimplexSolver.IterDescr iteration)

Description copied from class: SimplexStore

Update edge weights for non-basic (excluded) variables.

Specified by:

updatePrimalEdgeWeights in class SimplexStore

value

final double value(boolean phase1)

The current, phase 1 or 2, objective function value