Module ojalgo

Package org.ojalgo.optimisation.integer

Class NodeKey

java.lang.Object

org.ojalgo.optimisation.integer.NodeKey

All Implemented Interfaces:

java.lang.Comparable<NodeKey>

public final class NodeKey
extends java.lang.Object
implements java.lang.Comparable<NodeKey>

Nested Class Summary

Nested Classes

Modifier and Type	Class	Description
(package private) static class	NodeKey.IntArrayPool

Field Summary

Fields

Modifier and Type	Field	Description
static java.util.Comparator<NodeKey>	BREADTH_FIRST_SEARCH
int	depth	How far have we branched from the root
static java.util.Comparator<NodeKey>	DEPTH_FIRST_SEARCH
double	displacement	How much the branched on variable must be displaced because of the new constraint introduced with this node (each node introduces precisely 1 new upper or lower bound).
private static NumberContext	FEASIBILITY	Used for one thing only - to validate (log problems with) node solver results.
static java.util.Comparator<NodeKey>	FIFO_SEQUENCE
int	index	The index of the branched on variable.
static java.util.Comparator<NodeKey>	LARGE_DISPLACEMENT
static java.util.Comparator<NodeKey>	LIFO_SEQUENCE
static java.util.Comparator<NodeKey>	MAX_OBJECTIVE
static java.util.Comparator<NodeKey>	MIN_OBJECTIVE
(package private) static double	MINIMUM_DISPLACEMENT
private NodeKey.IntArrayPool	myIntArrayPool
private int[]	myLowerBounds
private boolean	mySignChanged
private int[]	myUpperBounds
private boolean	myUpperBranch
double	objective	The objective function value of the parent node.
long	parent	Parent node sequence number.
long	sequence	Node sequence number to keep track of in which order the nodes were created.
private static java.util.concurrent.atomic.AtomicLong	SEQUENCE_GENERATOR
static java.util.Comparator<NodeKey>	SMALL_DISPLACEMENT

Constructor Summary

Constructors

Modifier	Constructor	Description
private	NodeKey(int[] lowerBounds, int[] upperBounds, long parentSequenceNumber, int parentDepth, int integerIndexBranchedOn, double branchVariableDisplacement, double parentObjectiveFunctionValue, boolean signChanged, boolean upperBranch, NodeKey.IntArrayPool pool)
(package private)	NodeKey(ExpressionsBasedModel integerModel)

Method Summary

Modifier and Type	Method	Description
private void	append(java.lang.StringBuilder builder, int idx)
(package private) long	calculateTreeSize()
int	compareTo(NodeKey ref)
(package private) int[]	copyLowerBounds()
(package private) int[]	copyUpperBounds()
(package private) NodeKey	createLowerBranch(int branchIntegerIndex, double value, double objVal)
(package private) NodeKey	createUpperBranch(int branchIntegerIndex, double value, double objVal)
(package private) void	dispose()
(package private) void	enforceBounds(ExpressionsBasedModel model, int idx, ModelStrategy strategy)
(package private) void	enforceBounds(NodeSolver nodeSolver, ModelStrategy strategy)
(package private) boolean	equals(int[] lowerBounds, int[] upperBounds)
boolean	equals(java.lang.Object obj)
private double	feasible(int idx, double value, boolean validate)
(package private) java.math.BigDecimal	getLowerBound(int idx)
(package private) double	getMinimumDisplacement(int idx, double value)
(package private) java.math.BigDecimal	getUpperBound(int idx)
int	hashCode()
(package private) boolean	isLowerBranch()
(package private) boolean	isSignChanged()
(package private) boolean	isUpperBranch()
(package private) double	score(ModelStrategy strategy, boolean found)
(package private) void	setNodeState(ExpressionsBasedModel model, ModelStrategy strategy)
java.lang.String	toString()

Methods inherited from class java.lang.Object

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

Field Detail

MINIMUM_DISPLACEMENT

static final double MINIMUM_DISPLACEMENT

See Also:

Constant Field Values

BREADTH_FIRST_SEARCH

public static final java.util.Comparator<NodeKey> BREADTH_FIRST_SEARCH

DEPTH_FIRST_SEARCH

public static final java.util.Comparator<NodeKey> DEPTH_FIRST_SEARCH

FIFO_SEQUENCE

public static final java.util.Comparator<NodeKey> FIFO_SEQUENCE

LARGE_DISPLACEMENT

public static final java.util.Comparator<NodeKey> LARGE_DISPLACEMENT

LIFO_SEQUENCE

public static final java.util.Comparator<NodeKey> LIFO_SEQUENCE

MAX_OBJECTIVE

public static final java.util.Comparator<NodeKey> MAX_OBJECTIVE

MIN_OBJECTIVE

public static final java.util.Comparator<NodeKey> MIN_OBJECTIVE

SMALL_DISPLACEMENT

public static final java.util.Comparator<NodeKey> SMALL_DISPLACEMENT

FEASIBILITY

private static final NumberContext FEASIBILITY

Used for one thing only - to validate (log problems with) node solver results. Does not effect the algorithm.

SEQUENCE_GENERATOR

private static final java.util.concurrent.atomic.AtomicLong SEQUENCE_GENERATOR

depth

public final int depth

How far have we branched from the root

displacement

public final double displacement

How much the branched on variable must be displaced because of the new constraint introduced with this node (each node introduces precisely 1 new upper or lower bound).

index

public final int index

The index of the branched on variable.

objective

public final double objective

The objective function value of the parent node.

parent

public final long parent

Parent node sequence number.

sequence

public final long sequence

Node sequence number to keep track of in which order the nodes were created.

myIntArrayPool

private final NodeKey.IntArrayPool myIntArrayPool

myLowerBounds

private final int[] myLowerBounds

mySignChanged

private final boolean mySignChanged

myUpperBounds

private final int[] myUpperBounds

myUpperBranch

private final boolean myUpperBranch

Constructor Detail

NodeKey

private NodeKey(int[] lowerBounds,
                int[] upperBounds,
                long parentSequenceNumber,
                int parentDepth,
                int integerIndexBranchedOn,
                double branchVariableDisplacement,
                double parentObjectiveFunctionValue,
                boolean signChanged,
                boolean upperBranch,
                NodeKey.IntArrayPool pool)

NodeKey

NodeKey(ExpressionsBasedModel integerModel)

Method Detail

compareTo

public int compareTo(NodeKey ref)

Specified by:

compareTo in interface java.lang.Comparable<NodeKey>

equals

public boolean equals(java.lang.Object obj)

Overrides:

equals in class java.lang.Object

hashCode

public int hashCode()

Overrides:

hashCode in class java.lang.Object

toString

public java.lang.String toString()

Overrides:

toString in class java.lang.Object

append

private void append(java.lang.StringBuilder builder,
                    int idx)

feasible

private double feasible(int idx,
                        double value,
                        boolean validate)

calculateTreeSize

long calculateTreeSize()

copyLowerBounds

int[] copyLowerBounds()

copyUpperBounds

int[] copyUpperBounds()

createLowerBranch

NodeKey createLowerBranch(int branchIntegerIndex,
                          double value,
                          double objVal)

createUpperBranch

NodeKey createUpperBranch(int branchIntegerIndex,
                          double value,
                          double objVal)

dispose

void dispose()

enforceBounds

void enforceBounds(ExpressionsBasedModel model,
                   int idx,
                   ModelStrategy strategy)

enforceBounds

void enforceBounds(NodeSolver nodeSolver,
                   ModelStrategy strategy)

equals

boolean equals(int[] lowerBounds,
               int[] upperBounds)

getLowerBound

java.math.BigDecimal getLowerBound(int idx)

getMinimumDisplacement

double getMinimumDisplacement(int idx,
                              double value)

getUpperBound

java.math.BigDecimal getUpperBound(int idx)

isLowerBranch

boolean isLowerBranch()

isSignChanged

boolean isSignChanged()

isUpperBranch

boolean isUpperBranch()

score

double score(ModelStrategy strategy,
             boolean found)

setNodeState

void setNodeState(ExpressionsBasedModel model,
                  ModelStrategy strategy)