ca.pfv.spmf.algorithms.frequentpatterns.itemsettree

Class ItemsetTree

java.lang.Object

ca.pfv.spmf.algorithms.frequentpatterns.itemsettree.ItemsetTree

All Implemented Interfaces:

java.io.Serializable

public class ItemsetTree
extends java.lang.Object
implements java.io.Serializable

An implementation of the Itemset-tree It is based on the description in: Kubat, M., Hafez, A., Raghavan, V. V., Lekkala, J. R., Chen, W. K. (2003) Itemset Trees for Targeted Association Querying. Proc. of ICDE 2003. Copyright (c) 2008-2012 Philippe Fournier-Viger This file is part of the SPMF DATA MINING SOFTWARE (http://www.philippe-fournier-viger.com/spmf). SPMF is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by the Free Software Foundation, either version 3 of the License, or (at your option) any later version. SPMF is distributed in the hope that it will be useful, but WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for more details. You should have received a copy of the GNU General Public License along with SPMF. If not, see .

See Also:

Serialized Form

Constructor Summary

Constructors

Constructor and Description
ItemsetTree() Default constructor

Method Summary

Modifier and Type	Method and Description
void	addTransaction(int[] transaction) Add a transaction to the itemset tree.
void	buildTree(java.lang.String input) Build the itemset-tree based on an input file containing transactions
java.util.List<AssociationRuleIT>	generateRules(int[] s, int minsup, double minconf) Generate all association rules with a given itemset as antecedent.
HashTableIT	getFrequentItemsetSubsuming(int[] s) This method pass through the itemset tree to get all itemsets that are subsuming a given itemset "s" and their support.
HashTableIT	getFrequentItemsetSubsuming(int[] is, int minsup) Get the frequent itemsets subsuming a given itemset for a given minimum support value.
int	getSupportOfItemset(int[] s) Get the support of a given itemset s.
void	printStatistics() Print statistics about the time and maximum memory usage for the construction of the itemset tree.
void	printTree() Print the tree to System.out.
java.lang.String	toString() Return a string representation of the tree.

Methods inherited from class java.lang.Object

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

Constructor Detail

ItemsetTree

public ItemsetTree()

Default constructor

Method Detail

buildTree

public void buildTree(java.lang.String input)
               throws java.io.IOException

Build the itemset-tree based on an input file containing transactions

Parameters:

input - an input file

Throws:

java.io.IOException - exception if error while reading the file

addTransaction

public void addTransaction(int[] transaction)

Add a transaction to the itemset tree.

Parameters:

transaction - the transaction to be added (array of ints)

printStatistics

public void printStatistics()

Print statistics about the time and maximum memory usage for the construction of the itemset tree.

printTree

public void printTree()

Print the tree to System.out.

toString

public java.lang.String toString()

Return a string representation of the tree.

Overrides:

toString in class java.lang.Object

getSupportOfItemset

public int getSupportOfItemset(int[] s)

Get the support of a given itemset s.

Parameters:

s - the itemset

Returns:

the support as an integer.

getFrequentItemsetSubsuming

public HashTableIT getFrequentItemsetSubsuming(int[] s)

This method pass through the itemset tree to get all itemsets that are subsuming a given itemset "s" and their support. Note that this method may also return infrequent itemsets that can be filtered by additional processing after.

Parameters:

s - the itemset

Returns:

an hashtable countaining itemsets and their support.

getFrequentItemsetSubsuming

public HashTableIT getFrequentItemsetSubsuming(int[] is,
                                               int minsup)

Get the frequent itemsets subsuming a given itemset for a given minimum support value.

Parameters:

is - the itemset

minsup - the minimum support threshold (integer)

Returns:

an hashtable containing the frequent itemsets

generateRules

public java.util.List<AssociationRuleIT> generateRules(int[] s,
                                                       int minsup,
                                                       double minconf)

Generate all association rules with a given itemset as antecedent.

Parameters:

s - the itemset to be used as antecedent

minsup - the minsup threshold to be used

minconf - the minconf threshold to be used

Returns:

a list of association rules