Package org.apache.commons.math3.optimization.linear

Class SimplexTableau

  • All Implemented Interfaces:
    java.io.Serializable
    @Deprecated
class SimplexTableau
extends java.lang.Object
implements java.io.Serializable
    Deprecated.
    As of 3.1 (to be removed in 4.0).
    A tableau for use in the Simplex method.

    Example: 

       W |  Z |  x1 |  x2 |  x- | s1 |  s2 |  a1 |  RHS
 ---------------------------------------------------
  -1    0    0     0     0     0     0     1     0   <= phase 1 objective
   0    1   -15   -10    0     0     0     0     0   <= phase 2 objective
   0    0    1     0     0     1     0     0     2   <= constraint 1
   0    0    0     1     0     0     1     0     3   <= constraint 2
   0    0    1     1     0     0     0     1     4   <= constraint 3
    W: Phase 1 objective function
    Z: Phase 2 objective function
    x1 & x2: Decision variables
    x-: Extra decision variable to allow for negative values
    s1 & s2: Slack/Surplus variables
    a1: Artificial variable
    RHS: Right hand side

    Since:
    2.0

    • Field Summary

      Fields 
      Modifier and Type Field Description
      private java.util.List<java.lang.String> columnLabels
      Deprecated.
      The variables each column represents
      private java.util.List<LinearConstraint> constraints
      Deprecated.
      Linear constraints.
      private static double CUTOFF_THRESHOLD
      Deprecated.
      The cut-off threshold to zero-out entries.
      private static int DEFAULT_ULPS
      Deprecated.
      Default amount of error to accept in floating point comparisons (as ulps).
      private double epsilon
      Deprecated.
      Amount of error to accept when checking for optimality.
      private LinearObjectiveFunction f
      Deprecated.
      Linear objective function.
      private int maxUlps
      Deprecated.
      Amount of error to accept in floating point comparisons.
      private static java.lang.String NEGATIVE_VAR_COLUMN_LABEL
      Deprecated.
      Column label for negative vars.
      private int numArtificialVariables
      Deprecated.
      Number of artificial variables.
      private int numDecisionVariables
      Deprecated.
      Number of decision variables.
      private int numSlackVariables
      Deprecated.
      Number of slack variables.
      private boolean restrictToNonNegative
      Deprecated.
      Whether to restrict the variables to non-negative values.
      private static long serialVersionUID
      Deprecated.
      Serializable version identifier.
      private RealMatrix tableau
      Deprecated.
      Simple tableau.

    • Method Summary

      All Methods Static Methods Instance Methods Concrete Methods Deprecated Methods 
      Modifier and Type Method Description
      private void copyArray​(double[] src, double[] dest)
      Deprecated.
       
      protected RealMatrix createTableau​(boolean maximize)
      Deprecated.
      Create the tableau by itself.
      protected void divideRow​(int dividendRow, double divisor)
      Deprecated.
      Subtracts a multiple of one row from another.
      protected void dropPhase1Objective()
      Deprecated.
      Removes the phase 1 objective function, positive cost non-artificial variables, and the non-basic artificial variables from this tableau.
      boolean equals​(java.lang.Object other)
      Deprecated.
      protected int getArtificialVariableOffset()
      Deprecated.
      Get the offset of the first artificial variable.
      protected java.lang.Integer getBasicRow​(int col)
      Deprecated.
      Checks whether the given column is basic.
      private int getConstraintTypeCounts​(Relationship relationship)
      Deprecated.
      Get a count of constraints corresponding to a specified relationship.
      protected double[][] getData()
      Deprecated.
      Get the tableau data.
      protected double getEntry​(int row, int column)
      Deprecated.
      Get an entry of the tableau.
      protected int getHeight()
      Deprecated.
      Get the height of the tableau.
      protected static double getInvertedCoefficientSum​(RealVector coefficients)
      Deprecated.
      Get the -1 times the sum of all coefficients in the given array.
      protected int getNumArtificialVariables()
      Deprecated.
      Get the number of artificial variables.
      protected int getNumDecisionVariables()
      Deprecated.
      Get the number of decision variables.
      protected int getNumObjectiveFunctions()
      Deprecated.
      Get the number of objective functions in this tableau.
      protected int getNumSlackVariables()
      Deprecated.
      Get the number of slack variables.
      protected int getOriginalNumDecisionVariables()
      Deprecated.
      Get the original number of decision variables.
      protected int getRhsOffset()
      Deprecated.
      Get the offset of the right hand side.
      protected int getSlackVariableOffset()
      Deprecated.
      Get the offset of the first slack variable.
      protected PointValuePair getSolution()
      Deprecated.
      Get the current solution.
      protected int getWidth()
      Deprecated.
      Get the width of the tableau.
      int hashCode()
      Deprecated.
      protected void initializeColumnLabels()
      Deprecated.
      Initialize the labels for the columns.
      (package private) boolean isOptimal()
      Deprecated.
      Returns whether the problem is at an optimal state.
      private LinearConstraint normalize​(LinearConstraint constraint)
      Deprecated.
      Get a new equation equivalent to this one with a positive right hand side.
      java.util.List<LinearConstraint> normalizeConstraints​(java.util.Collection<LinearConstraint> originalConstraints)
      Deprecated.
      Get new versions of the constraints which have positive right hand sides.
      private void readObject​(java.io.ObjectInputStream ois)
      Deprecated.
      Deserialize the instance.
      protected void setEntry​(int row, int column, double value)
      Deprecated.
      Set an entry of the tableau.
      protected void subtractRow​(int minuendRow, int subtrahendRow, double multiple)
      Deprecated.
      Subtracts a multiple of one row from another.
      private void writeObject​(java.io.ObjectOutputStream oos)
      Deprecated.
      Serialize the instance.

      • Methods inherited from class java.lang.Object

        clone, finalize, getClass, notify, notifyAll, toString, wait, wait, wait

    • Field Detail

      • NEGATIVE_VAR_COLUMN_LABEL

        private static final java.lang.String NEGATIVE_VAR_COLUMN_LABEL
        Deprecated.
        Column label for negative vars.
        See Also:
        Constant Field Values

      • DEFAULT_ULPS

        private static final int DEFAULT_ULPS
        Deprecated.
        Default amount of error to accept in floating point comparisons (as ulps).
        See Also:
        Constant Field Values

      • CUTOFF_THRESHOLD

        private static final double CUTOFF_THRESHOLD
        Deprecated.
        The cut-off threshold to zero-out entries.
        See Also:
        Constant Field Values

      • serialVersionUID

        private static final long serialVersionUID
        Deprecated.
        Serializable version identifier.
        See Also:
        Constant Field Values

      • constraints

        private final java.util.List<LinearConstraint> constraints
        Deprecated.
        Linear constraints.

      • restrictToNonNegative

        private final boolean restrictToNonNegative
        Deprecated.
        Whether to restrict the variables to non-negative values.

      • columnLabels

        private final java.util.List<java.lang.String> columnLabels
        Deprecated.
        The variables each column represents

      • tableau

        private transient RealMatrix tableau
        Deprecated.
        Simple tableau.

      • numDecisionVariables

        private final int numDecisionVariables
        Deprecated.
        Number of decision variables.

      • numSlackVariables

        private final int numSlackVariables
        Deprecated.
        Number of slack variables.

      • numArtificialVariables

        private int numArtificialVariables
        Deprecated.
        Number of artificial variables.

      • epsilon

        private final double epsilon
        Deprecated.
        Amount of error to accept when checking for optimality.

      • maxUlps

        private final int maxUlps
        Deprecated.
        Amount of error to accept in floating point comparisons.

    • Constructor Detail

      • SimplexTableau

        SimplexTableau​(LinearObjectiveFunction f,
               java.util.Collection<LinearConstraint> constraints,
               GoalType goalType,
               boolean restrictToNonNegative,
               double epsilon)
        Deprecated.
        Build a tableau for a linear problem.
        Parameters:
        f - linear objective function
        constraints - linear constraints
        goalType - type of optimization goal: either GoalType.MAXIMIZE or GoalType.MINIMIZE
        restrictToNonNegative - whether to restrict the variables to non-negative values
        epsilon - amount of error to accept when checking for optimality

      • SimplexTableau

        SimplexTableau​(LinearObjectiveFunction f,
               java.util.Collection<LinearConstraint> constraints,
               GoalType goalType,
               boolean restrictToNonNegative,
               double epsilon,
               int maxUlps)
        Deprecated.
        Build a tableau for a linear problem.
        Parameters:
        f - linear objective function
        constraints - linear constraints
        goalType - type of optimization goal: either GoalType.MAXIMIZE or GoalType.MINIMIZE
        restrictToNonNegative - whether to restrict the variables to non-negative values
        epsilon - amount of error to accept when checking for optimality
        maxUlps - amount of error to accept in floating point comparisons

    • Method Detail

      • initializeColumnLabels

        protected void initializeColumnLabels()
        Deprecated.
        Initialize the labels for the columns.

      • createTableau

        protected RealMatrix createTableau​(boolean maximize)
        Deprecated.
        Create the tableau by itself.
        Parameters:
        maximize - if true, goal is to maximize the objective function
        Returns:
        created tableau

      • normalizeConstraints

        public java.util.List<LinearConstraint> normalizeConstraints​(java.util.Collection<LinearConstraint> originalConstraints)
        Deprecated.
        Get new versions of the constraints which have positive right hand sides.
        Parameters:
        originalConstraints - original (not normalized) constraints
        Returns:
        new versions of the constraints

      • normalize

        private LinearConstraint normalize​(LinearConstraint constraint)
        Deprecated.
        Get a new equation equivalent to this one with a positive right hand side.
        Parameters:
        constraint - reference constraint
        Returns:
        new equation

      • getNumObjectiveFunctions

        protected final int getNumObjectiveFunctions()
        Deprecated.
        Get the number of objective functions in this tableau.
        Returns:
        2 for Phase 1. 1 for Phase 2.

      • getConstraintTypeCounts

        private int getConstraintTypeCounts​(Relationship relationship)
        Deprecated.
        Get a count of constraints corresponding to a specified relationship.
        Parameters:
        relationship - relationship to count
        Returns:
        number of constraint with the specified relationship

      • getInvertedCoefficientSum

        protected static double getInvertedCoefficientSum​(RealVector coefficients)
        Deprecated.
        Get the -1 times the sum of all coefficients in the given array.
        Parameters:
        coefficients - coefficients to sum
        Returns:
        the -1 times the sum of all coefficients in the given array.

      • getBasicRow

        protected java.lang.Integer getBasicRow​(int col)
        Deprecated.
        Checks whether the given column is basic.
        Parameters:
        col - index of the column to check
        Returns:
        the row that the variable is basic in. null if the column is not basic

      • dropPhase1Objective

        protected void dropPhase1Objective()
        Deprecated.
        Removes the phase 1 objective function, positive cost non-artificial variables, and the non-basic artificial variables from this tableau.

      • copyArray

        private void copyArray​(double[] src,
                       double[] dest)
        Deprecated.
        Parameters:
        src - the source array
        dest - the destination array

      • isOptimal

        boolean isOptimal()
        Deprecated.
        Returns whether the problem is at an optimal state.
        Returns:
        whether the model has been solved

      • getSolution

        protected PointValuePair getSolution()
        Deprecated.
        Get the current solution.
        Returns:
        current solution

      • divideRow

        protected void divideRow​(int dividendRow,
                         double divisor)
        Deprecated.
        Subtracts a multiple of one row from another.

        After application of this operation, the following will hold: 

        minuendRow = minuendRow - multiple * subtrahendRow
        Parameters:
        dividendRow - index of the row
        divisor - value of the divisor

      • subtractRow

        protected void subtractRow​(int minuendRow,
                           int subtrahendRow,
                           double multiple)
        Deprecated.
        Subtracts a multiple of one row from another.

        After application of this operation, the following will hold: 

        minuendRow = minuendRow - multiple * subtrahendRow
        Parameters:
        minuendRow - row index
        subtrahendRow - row index
        multiple - multiplication factor

      • getWidth

        protected final int getWidth()
        Deprecated.
        Get the width of the tableau.
        Returns:
        width of the tableau

      • getHeight

        protected final int getHeight()
        Deprecated.
        Get the height of the tableau.
        Returns:
        height of the tableau

      • getEntry

        protected final double getEntry​(int row,
                                int column)
        Deprecated.
        Get an entry of the tableau.
        Parameters:
        row - row index
        column - column index
        Returns:
        entry at (row, column)

      • setEntry

        protected final void setEntry​(int row,
                              int column,
                              double value)
        Deprecated.
        Set an entry of the tableau.
        Parameters:
        row - row index
        column - column index
        value - for the entry

      • getSlackVariableOffset

        protected final int getSlackVariableOffset()
        Deprecated.
        Get the offset of the first slack variable.
        Returns:
        offset of the first slack variable

      • getArtificialVariableOffset

        protected final int getArtificialVariableOffset()
        Deprecated.
        Get the offset of the first artificial variable.
        Returns:
        offset of the first artificial variable

      • getRhsOffset

        protected final int getRhsOffset()
        Deprecated.
        Get the offset of the right hand side.
        Returns:
        offset of the right hand side

      • getNumDecisionVariables

        protected final int getNumDecisionVariables()
        Deprecated.
        Get the number of decision variables.

        If variables are not restricted to positive values, this will include 1 extra decision variable to represent the absolute value of the most negative variable.

        Returns:
        number of decision variables
        See Also:
        getOriginalNumDecisionVariables()

      • getOriginalNumDecisionVariables

        protected final int getOriginalNumDecisionVariables()
        Deprecated.
        Get the original number of decision variables.
        Returns:
        original number of decision variables
        See Also:
        getNumDecisionVariables()

      • getNumSlackVariables

        protected final int getNumSlackVariables()
        Deprecated.
        Get the number of slack variables.
        Returns:
        number of slack variables

      • getNumArtificialVariables

        protected final int getNumArtificialVariables()
        Deprecated.
        Get the number of artificial variables.
        Returns:
        number of artificial variables

      • getData

        protected final double[][] getData()
        Deprecated.
        Get the tableau data.
        Returns:
        tableau data

      • equals

        public boolean equals​(java.lang.Object other)
        Deprecated.
        Overrides:
        equals in class java.lang.Object

      • hashCode

        public int hashCode()
        Deprecated.
        Overrides:
        hashCode in class java.lang.Object

      • writeObject

        private void writeObject​(java.io.ObjectOutputStream oos)
                  throws java.io.IOException
        Deprecated.
        Serialize the instance.
        Parameters:
        oos - stream where object should be written
        Throws:
        java.io.IOException - if object cannot be written to stream

      • readObject

        private void readObject​(java.io.ObjectInputStream ois)
                 throws java.lang.ClassNotFoundException,
                        java.io.IOException
        Deprecated.
        Deserialize the instance.
        Parameters:
        ois - stream from which the object should be read
        Throws:
        java.lang.ClassNotFoundException - if a class in the stream cannot be found
        java.io.IOException - if object cannot be read from the stream