JaCoP.constraints.knapsack
Class TreeLeaf

java.lang.Object
  JaCoP.constraints.knapsack.TreeNode
      JaCoP.constraints.knapsack.TreeLeaf

public final class TreeLeaf
extends TreeNode

It contains information required by the leaf node of the item tree.

Author:

Radoslaw Szymanek and Wadeck Follonier

Field Summary

double	efficiency It specifies the efficiency of the item in the leaf.
int	positionInTheTree It specifies the position in the tree.
int	previousMaxQ It specifies the maximal value of quantity variable after the last consistency check.
int	previousMinQ It specifies the minimal value of quantity variable after the last consistency check.
int	profitOfOne It store the profit of one instance of the item stored in this leaf.
IntVar	quantity It specifies the finite domain variable denoting the allowed quantity of the item,
int	slice It represents the offset from the minimal value.
int	weightOfOne It stores the weight of one instance of the item stored in this leaf.

Fields inherited from class JaCoP.constraints.knapsack.TreeNode

left, leftNeighbor, parent, right, rightNeighbor

Constructor Summary

TreeLeaf(IntVar quantity, int weight, int profit, int positionInTheTree)
It creates a leaf in the tree of items.

Method Summary

double	getEfficiency() It returns computed beforehand the efficiency of the item stored in this tree leaf.
int	getProfitOfOne()
int	getPSum() It does not recompute sum of profits.
IntVar	getVariable()
int	getWeightOfOne()
int	getWMax() It does not recompute the maximum of weights.
int	getWSum() It does not recompute sum of weights.
boolean	hasMaxChanged() Used to know the changes that occurred
boolean	hasMinChanged() Used to know the changes that occurred
boolean	isLeaf()
int	lastIncreasedOfMin() Used to know the changes that occurred
int	max()
int	min()
java.lang.String	nodeToString() It generates description of the node only.
void	recomputeDown(Tree tree) This function recomputes the attributes of this node after recomputing the left and right subtree.
void	recomputeUp(Tree tree) This function is used to recompute the attributes of all nodes on the way to root from this node.
java.lang.String	toString()
void	updateInternalValues(Tree tree) Only used in removeLevelLate(), update the internal value like previous and slice.

Methods inherited from class JaCoP.constraints.knapsack.TreeNode

setLeftNeighbor, setRightNeighbor

Methods inherited from class java.lang.Object

equals, getClass, hashCode, notify, notifyAll, wait, wait, wait

Field Detail

quantity

public final IntVar quantity

It specifies the finite domain variable denoting the allowed quantity of the item,

efficiency

public final double efficiency

It specifies the efficiency of the item in the leaf.

previousMaxQ

public int previousMaxQ

It specifies the maximal value of quantity variable after the last consistency check. It is used to determine if the maximal value of the quantity variable has changed since the last execution of the consistency function.

previousMinQ

public int previousMinQ

It specifies the minimal value of quantity variable after the last consistency check. It is used to determine if the minimal value of the quantity variable has changed since the last execution of the consistency function.

weightOfOne

public final int weightOfOne

It stores the weight of one instance of the item stored in this leaf.

profitOfOne

public final int profitOfOne

It store the profit of one instance of the item stored in this leaf.

slice

public int slice

It represents the offset from the minimal value. Slice of value 1 means that 1 item has been already counted in capacity and profit of the knapsack and quantity variable should be offset by one. Both min and max values will be reduced by one.

positionInTheTree

public int positionInTheTree

It specifies the position in the tree.

Constructor Detail

TreeLeaf

public TreeLeaf(IntVar quantity,
                int weight,
                int profit,
                int positionInTheTree)

It creates a leaf in the tree of items.

Parameters:

quantity - finite domain variable specifying the quantity.

weight - it specifies the weight of one instance of the item.

profit - it specifies the profit of one instance of the item.

positionInTheTree - it specifies the position in the tree.

Method Detail

getVariable

public final IntVar getVariable()

Returns:

The variable stored in this leaf

getProfitOfOne

public int getProfitOfOne()

Returns:

The profit of one unit of the variable

getWeightOfOne

public int getWeightOfOne()

Returns:

The weight of one unit of the variable

hasMinChanged

public final boolean hasMinChanged()

Used to know the changes that occurred

Returns:

If the minimum has changed

lastIncreasedOfMin

public final int lastIncreasedOfMin()

Used to know the changes that occurred

Returns:

The last change of the minimum

hasMaxChanged

public final boolean hasMaxChanged()

Used to know the changes that occurred

Returns:

If the maximum has changed

getWMax

public final int getWMax()

Description copied from class: TreeNode

It does not recompute the maximum of weights.

Overrides:

getWMax in class TreeNode

Returns:

The previously computed maximum weight of its children

getWSum

public final int getWSum()

Description copied from class: TreeNode

It does not recompute sum of weights.

Overrides:

getWSum in class TreeNode

Returns:

The previously computed sum of weights of its children

getPSum

public final int getPSum()

Description copied from class: TreeNode

It does not recompute sum of profits.

Overrides:

getPSum in class TreeNode

Returns:

The previously computed sum of profits of its children

isLeaf

public final boolean isLeaf()

Overrides:

isLeaf in class TreeNode

Returns:

true if the node is a leaf, false otherwise.

getEfficiency

public final double getEfficiency()

It returns computed beforehand the efficiency of the item stored in this tree leaf.

Returns:

the efficiency of the item stored at this computer.

toString

public final java.lang.String toString()

Overrides:

toString in class TreeNode

nodeToString

public final java.lang.String nodeToString()

Description copied from class: TreeNode

It generates description of the node only.

Overrides:

nodeToString in class TreeNode

Returns:

the description containing values of all node internal attributes.

updateInternalValues

public void updateInternalValues(Tree tree)

Only used in removeLevelLate(), update the internal value like previous and slice. It does not updates anything else in the tree.

Parameters:

tree - it specifies the tree to which this leaf belongs too.

min

public final int min()

Returns:

The minimum value of the variable after slicing.

max

public final int max()

Returns:

The maximum value of the variable after slicing

recomputeDown

public void recomputeDown(Tree tree)

Description copied from class: TreeNode

This function recomputes the attributes of this node after recomputing the left and right subtree.

Overrides:

recomputeDown in class TreeNode

Parameters:

tree - It is required by leaves so tree atributes like alreadyUsedCapacity are properly updated.

recomputeUp

public void recomputeUp(Tree tree)

Description copied from class: TreeNode

This function is used to recompute the attributes of all nodes on the way to root from this node. It assumes that left and right subtree have a correct values for their attributes.

Overrides:

recomputeUp in class TreeNode

Parameters:

tree - only added to be in agreement with the function template for leaf which need information about tree it belongs to.