Module ojalgo
Package org.ojalgo.optimisation.linear

Class SimplexStore

    • Field Detail

      • myLowerBounds

        private final double[] myLowerBounds

      • myRemainingArtificials

        private int myRemainingArtificials

      • myToStringList

        private final java.util.List<java.lang.String> myToStringList

      • myUpperBounds

        private final double[] myUpperBounds

      • edgeWeights

        final double[] edgeWeights
        Either the primal or dual devex edge weights, depending on the algorithm used. Sized so that it can hold either.

      • excluded

        final int[] excluded
        excluded == not in the basis

      • included

        final int[] included
        included == in the basis

      • m

        final int m
        The number of constraints (upper, lower and equality)

      • n

        final int n
        The number of variables totally (all kinds)

    • Method Detail

      • toString

        public java.lang.String toString()
        Overrides:
        toString in class java.lang.Object

      • shiftColumn

        protected void shiftColumn​(int col,
                           double shift)

      • constraintsBody

        abstract Mutate2D constraintsBody()
        The simplex' constraints body (including the parts corresponding to slack and artificial variables).

      • constraintsRHS

        abstract Mutate1D constraintsRHS()
        The simplex' constraints RHS.

      • copyBasicSolution

        abstract void copyBasicSolution​(double[] solution)

      • countRemainingArtificials

        final int countRemainingArtificials()
        The number of artificial variables in the basis.

      • extractSolution

        final double[] extractSolution()

      • extractValue

        abstract double extractValue()

      • generateCutCandidates

        final java.util.Collection<Equation> generateCutCandidates​(boolean[] integer,
                                                           NumberContext accuracy,
                                                           double fractionality,
                                                           double[] shift)
        When SimplexSolver is used as node solver for IntegerSolver this method generates cut candidates.

      • getCost

        abstract double getCost​(int i)

      • getCurrentElement

        abstract double getCurrentElement​(SimplexSolver.ExitInfo exit,
                                  int je)
        The current (tableau) constraint body element.

      • getCurrentElement

        abstract double getCurrentElement​(int i,
                                  SimplexSolver.EnterInfo enter)
        The current (tableau) constraint body element.

      • getCurrentRHS

        abstract double getCurrentRHS​(int i)
        The current (tableau) constraint RHS.

      • getInfeasibility

        abstract double getInfeasibility​(int i)

      • getLowerBound

        final double getLowerBound​(int index)

      • getLowerBounds

        final double[] getLowerBounds()

      • getLowerGap

        final double getLowerGap​(int i)
        The "distance" from the current basic value to the lower bound.

      • getReducedCost

        abstract double getReducedCost​(int je)

      • getUpperBound

        final double getUpperBound​(int index)

      • getUpperBounds

        final double[] getUpperBounds()

      • getUpperGap

        final double getUpperGap​(int i)
        The "distance" from the current basic value to the upper bound.

      • isArtificial

        final boolean isArtificial​(int col)

      • isExcluded

        final boolean isExcluded​(int index)

      • isIncluded

        final boolean isIncluded​(int index)

      • isNegated

        final boolean isNegated​(int j)

      • isPrintable

        final boolean isPrintable()
        The problem is small enough to be explicitly printed/logged – log the entire tableau at each iteration when debugging.

      • isRemainingArtificials

        final boolean isRemainingArtificials()
        Are there any artificial variables in the basis?

      • objective

        abstract Mutate1D objective()
        The objective function.

      • phase1

        abstract <T extends Mutate1D & Access1D<java.lang.Double>> T phase1()
        The phase-1 objective function.

      • prepareToIterate

        abstract void prepareToIterate()

      • removePhase1

        abstract void removePhase1()

      • resetBasis

        void resetBasis​(int[] newBasis)
        Everything that is not in the basis is set to be in at lower bound.

      • resetEdgeWeights

        void resetEdgeWeights()

      • setupClassicPhase1Objective

        abstract void setupClassicPhase1Objective()

      • sliceBodyRow

        abstract Primitive1D sliceBodyRow​(int row)

      • sliceDualVariables

        abstract Primitive1D sliceDualVariables()

      • update

        final void update​(int exit,
                  int exclEnter)

      • updateDualEdgeWeights

        abstract void updateDualEdgeWeights​(SimplexSolver.IterDescr iteration)
        Update edge weights for basic (included) variables.

      • updatePrimalEdgeWeights

        abstract void updatePrimalEdgeWeights​(SimplexSolver.IterDescr iteration)
        Update edge weights for non-basic (excluded) variables.

      • updateRange

        boolean updateRange​(int index,
                    double lower,
                    double upper)