CHARM

class PAMI.frequentPattern.closed.CHARM.CHARM(iFile, minSup, sep='\t')

Bases: _frequentPatterns

Description:

CHARM is an algorithm to discover closed frequent patterns in a transactional database. Closed frequent patterns are patterns if there exists no superset that has the same support count as this original itemset. This algorithm employs depth-first search technique to find the complete set of closed frequent patterns in a

Reference:

Mohammed J. Zaki and Ching-Jui Hsiao, CHARM: An Efficient Algorithm for Closed Itemset Mining, Proceedings of the 2002 SIAM, SDM. 2002, 457-473, https://doi.org/10.1137/1.9781611972726.27

Parameters:

• iFile – str : Name of the Input file to mine complete set of frequent patterns

• oFile – str : Name of the output file to store complete set of frequent patterns

• minSup – int or float or str : The user can specify minSup either in count or proportion of database size. If the program detects the data type of minSup is integer, then it treats minSup is expressed in count.

• sep – str : This variable is used to distinguish items from one another in a transaction. The default seperator is tab space. However, the users can override their default separator.

Attributes:

startTimefloat

To record the start time of the mining process

endTimefloat

To record the completion time of the mining process

finalPatternsdict

Storing the complete set of patterns in a dictionary variable

memoryUSSfloat

To store the total amount of USS memory consumed by the program

memoryRSSfloat

To store the total amount of RSS memory consumed by the program

Databaselist

To store the transactions of a database in list

mapSupportDictionary

To maintain the information of item and their frequency

lnoint

it represents the total no of transactions

treeclass

it represents the Tree class

itemSetCountint

it represents the total no of patterns

finalPatternsdict

it represents to store the patterns

tidListdict

stores the timestamps of an item

hashingdict

stores the patterns with their support to check for the closed property

Methods to execute code on terminal

Format:

(.venv) $ python3 CHARM.py <inputFile> <outputFile> <minSup>

Example Usage:

(.venv) $ python3 CHARM.py sampleDB.txt patterns.txt 10.0

Note

minSup will be considered in percentage of database transactions

Importing this algorithm into a python program

from PAMI.frequentPattern.closed import CHARM as alg

obj = alg.CHARM(iFile, minSup)

obj.mine()

frequentPatterns = obj.getPatterns()

print("Total number of Closed Frequent Patterns:", len(frequentPatterns))

obj.savePatterns(oFile)

Df = obj.getPatternsAsDataFrame()

memUSS = obj.getMemoryUSS()

print("Total Memory in USS:", memUSS)

memRSS = obj.getMemoryRSS()

print("Total Memory in RSS", memRSS)

run = obj.getRuntime()

print("Total ExecutionTime in seconds:", run)

Credits:

The complete program was written by P.Likhitha under the supervision of Professor Rage Uday Kiran.

getMemoryRSS()

Total amount of RSS memory consumed by the mining process will be retrieved from this function :return: returning RSS memory consumed by the mining process :rtype: float

getMemoryUSS()

Total amount of USS memory consumed by the mining process will be retrieved from this function :return: returning USS memory consumed by the mining process :rtype: float

getPatterns()

Function to send the set of frequent patterns after completion of the mining process :return: returning frequent patterns :rtype: dict

getPatternsAsDataFrame()

Storing final frequent patterns in a dataframe :return: returning frequent patterns in a dataframe :rtype: pd.DataFrame

getRuntime()

Calculating the total amount of runtime taken by the mining process :return: returning total amount of runtime taken by the mining process :rtype: float

mine()

Mining process will start from here by extracting the frequent patterns from the database. It performs prefix equivalence to generate the combinations and closed frequent patterns.

printResults()

This function is used to print the results

save(outFile)

Complete set of frequent patterns will be loaded in to an output file :param outFile: name of the output file :type outFile: csvfile

startMine()

Mining process will start from here by extracting the frequent patterns from the database. It performs prefix equivalence to generate the combinations and closed frequent patterns.