ca.pfv.spmf.algorithms.sequentialpatterns.BIDE_and_prefixspan

Class PseudoSequenceBIDE

java.lang.Object

ca.pfv.spmf.algorithms.sequentialpatterns.BIDE_and_prefixspan.PseudoSequence

ca.pfv.spmf.algorithms.sequentialpatterns.BIDE_and_prefixspan.PseudoSequenceBIDE

public class PseudoSequenceBIDE
extends PseudoSequence

This represents a sequence from a projected database (as based in BIDE+). Since it is a projected sequence, it makes reference to the original Sequence.Java class used by BIDE+. This class also include several methods for calculating the maximum periods, semi-maximum periods, etc. as required by the BIDE+ algorithm. These methods are quite complex so if you want to understand them, it is recommended to read the BIDE+ paper carefully before reading the code. 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 .

Constructor Summary

Constructors

Constructor and Description
PseudoSequenceBIDE(Sequence sequence, int indexItemset, int indexItem) Constructor of a pseudo-sequence based on an original sequence (overloaded)

Method Summary

Modifier and Type	Method and Description
PseudoSequenceBIDE	getIthSemiMaximumPeriodOfAPrefix(java.util.List<Itemset> prefix, int i) Get the ith semi-maximum period of a prefix sequence for this sequence S.
int	getSizeOfItemsetAt(int index) Check if a given itemset is the last itemset (overloaded).
int	size() Return the size of this pseudo-sequence in terms of itemsets.
java.lang.String	toString() Get a string representation of this sequence.

Methods inherited from class ca.pfv.spmf.algorithms.sequentialpatterns.BIDE_and_prefixspan.PseudoSequence

equals, getItemAtInItemsetAt, getItemset, getOriginalSequence, print

Methods inherited from class java.lang.Object

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

Constructor Detail

PseudoSequenceBIDE

public PseudoSequenceBIDE(Sequence sequence,
                          int indexItemset,
                          int indexItem)

Constructor of a pseudo-sequence based on an original sequence (overloaded)

Parameters:

sequence - the original sequence

indexItemset - the position of the itemset where the pseudo sequence starts (!=0 if it is cut at left)

indexItem - the position of the item where the pseudo sequence starts (!=0 if it is cut at left)

Method Detail

getSizeOfItemsetAt

public int getSizeOfItemsetAt(int index)

Check if a given itemset is the last itemset (overloaded).

Overrides:

getSizeOfItemsetAt in class PseudoSequence

Parameters:

index - the position of the itemset

Returns:

true if yes.

toString

public java.lang.String toString()

Get a string representation of this sequence.

Overrides:

toString in class PseudoSequence

size

public int size()

Description copied from class: PseudoSequence

Return the size of this pseudo-sequence in terms of itemsets.

Returns:

the size.

getIthSemiMaximumPeriodOfAPrefix

public PseudoSequenceBIDE getIthSemiMaximumPeriodOfAPrefix(java.util.List<Itemset> prefix,
                                                           int i)

Get the ith semi-maximum period of a prefix sequence for this sequence S. The ith semi-maximum period of the prefix Sp in S is : * if 0 < i <= n, it is the piece of sequence between the end of the first instance of prefix e1... ei-1 in S and the ith last-in-first appearance with respect to prefix Sp * if i = 0, it is the piece of sequence in S located before the first last-in-first appearance with respect to prefix Sp.