ca.pfv.spmf.algorithms.sequentialpatterns.clospan_AGP

Class AlgoCloSpan

java.lang.Object

ca.pfv.spmf.algorithms.sequentialpatterns.clospan_AGP.AlgoCloSpan

public class AlgoCloSpan
extends java.lang.Object

This is an implementation of the CloSpan algorithm. CloSpan was proposed by X. Yan et al. 2003.

NOTE: This implementation saves the pattern to a file as soon as they are found or can keep the pattern into memory if no output path is provided by the user.

Constructor Summary

Constructors

Constructor and Description
AlgoCloSpan(double minSupRelative, AbstractionCreator creator, boolean findClosedPatterns, boolean executePruningMethods) Standard constructor.

Method Summary

Modifier and Type	Method and Description
void	clear() It clears all the attributes of AlgoPrefixSpan class
double	getAbsoluteMinSupport() It gets the absolute minimum support, i.e.
int	getNumberOfFrequentPatterns()
long	getRunningTime() It gets the total time spent by the algoritm in its execution.
java.lang.String	printStatistics() Method to get the outlined information about the search for frequent sequences by means of CloSpan algorithm s a string
void	runAlgorithm(SequenceDatabase database, boolean keepPatterns, boolean verbose, java.lang.String outputFilePath) Method that starts the execution of the algorithm.

Methods inherited from class java.lang.Object

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

Constructor Detail

AlgoCloSpan

public AlgoCloSpan(double minSupRelative,
                   AbstractionCreator creator,
                   boolean findClosedPatterns,
                   boolean executePruningMethods)

Standard constructor. It takes the relative minimum support threshold (from 1 up to 0) and an abstraction creator

Parameters:

minSupRelative - the relative minimum support threshold

creator - the abstraction creator

findClosedPatterns - flag to indicate if we are interesting in only finding the closed sequences

Method Detail

runAlgorithm

public void runAlgorithm(SequenceDatabase database,
                         boolean keepPatterns,
                         boolean verbose,
                         java.lang.String outputFilePath)
                  throws java.io.IOException

Method that starts the execution of the algorithm.

Parameters:

database - The original database in which we apply PrefixSpan

keepPatterns - Flag indicating if the user want to keep the frequent patterns or he just want the amount of them

verbose - Flag for debugging purposes

outputFilePath - Path pointing out to the file where the output, composed of frequent patterns, has to be kept. If, conversely, this parameter is null, we understand that the user wants the output in the main memory

Throws:

java.io.IOException

printStatistics

public java.lang.String printStatistics()

Method to get the outlined information about the search for frequent sequences by means of CloSpan algorithm s a string

Returns:

a string containing this information

getNumberOfFrequentPatterns

public int getNumberOfFrequentPatterns()

getRunningTime

public long getRunningTime()

It gets the total time spent by the algoritm in its execution.

Returns:

the time

getAbsoluteMinSupport

public double getAbsoluteMinSupport()

It gets the absolute minimum support, i.e. the minimum number of database sequences where a pattern has to appear

Returns:

the minimum support

clear

public void clear()

It clears all the attributes of AlgoPrefixSpan class