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Ich habe Titel für jede Spalte in der CSV-Datei gespeichert und möchte Assoziationsregeln zwischen den Titeln und diesem Code für apriori algo returns itemsets und ihre Assoziationsregeln wie kann ich ändern sie gehört den Titel (Name der Kategorie Artikel zu erhalten, anstatt Gegenstände selbstWie man den Titel des Tupels anstelle des Tupelwerts erhält
"""
Description : Simple Python implementation of the Apriori Algorithm
Usage:
$python apriori.py -f DATASET.csv -s minSupport -c minConfidence
$python apriori.py -f DATASET.csv -s 0.15 -c 0.6
"""
import sys
from itertools import chain, combinations
from collections import defaultdict
from optparse import OptionParser
def subsets(arr):
""" Returns non empty subsets of arr"""
return chain(*[combinations(arr, i + 1) for i, a in enumerate(arr)])
def returnItemsWithMinSupport(itemSet, transactionList, minSupport, freqSet):
"""calculates the support for items in the itemSet and returns a subset
of the itemSet each of whose elements satisfies the minimum support"""
_itemSet = set()
localSet = defaultdict(int)
for item in itemSet:
for transaction in transactionList:
if item.issubset(transaction):
freqSet[item] += 1
localSet[item] += 1
for item, count in localSet.items():
support = float(count)/len(transactionList)
if support >= minSupport:
_itemSet.add(item)
return _itemSet
def joinSet(itemSet, length):
"""Join a set with itself and returns the n-element itemsets"""
return set([i.union(j) for i in itemSet for j in itemSet if len(i.union(j)) == length])
def getItemSetTransactionList(data_iterator):
transactionList = list()
itemSet = set()
for record in data_iterator:
transaction = frozenset(record)
transactionList.append(transaction)
for item in transaction:
itemSet.add(frozenset([item])) # Generate 1-itemSets
return itemSet, transactionList
def runApriori(data_iter, minSupport, minConfidence):
"""
run the apriori algorithm. data_iter is a record iterator
Return both:
- items (tuple, support)
- rules ((pretuple, posttuple), confidence)
"""
itemSet, transactionList = getItemSetTransactionList(data_iter)
freqSet = defaultdict(int)
largeSet = dict()
# Global dictionary which stores (key=n-itemSets,value=support)
# which satisfy minSupport
assocRules = dict()
# Dictionary which stores Association Rules
oneCSet = returnItemsWithMinSupport(itemSet,
transactionList,
minSupport,
freqSet)
currentLSet = oneCSet
k = 2
while(currentLSet != set([])):
largeSet[k-1] = currentLSet
currentLSet = joinSet(currentLSet, k)
currentCSet = returnItemsWithMinSupport(currentLSet,
transactionList,
minSupport,
freqSet)
currentLSet = currentCSet
k = k + 1
def getSupport(item):
"""local function which Returns the support of an item"""
return float(freqSet[item])/len(transactionList)
toRetItems = []
for key, value in largeSet.items():
toRetItems.extend([(tuple(item), getSupport(item))
for item in value])
toRetRules = []
for key, value in largeSet.items()[1:]:
for item in value:
_subsets = map(frozenset, [x for x in subsets(item)])
for element in _subsets:
remain = item.difference(element)
if len(remain) > 0:
confidence = getSupport(item)/getSupport(element)
if confidence >= minConfidence:
toRetRules.append(((tuple(element), tuple(remain)),
confidence))
return toRetItems, toRetRules
def printResults(items, rules):
"""prints the generated itemsets sorted by support and the confidence rules sorted by confidence"""
for item, support in sorted(items, key=lambda (item, support): support):
print "item: %s , %.3f" % (str(item), support)
print "\n------------------------ RULES:"
for rule, confidence in sorted(rules, key=lambda (rule, confidence): confidence):
pre, post = rule
print "Rule: %s ==> %s , %.3f" % (str(pre), str(post), confidence)
def dataFromFile(fname):
"""Function which reads from the file and yields a generator"""
file_iter = open(fname, 'rU')
for line in file_iter:
line = line.strip().rstrip(',') # Remove trailing comma
record = frozenset(line.split(','))
yield record
if __name__ == "__main__":
optparser = OptionParser()
optparser.add_option('-f', '--inputFile',
dest='input',
help='filename containing csv',
default=None)
optparser.add_option('-s', '--minSupport',
dest='minS',
help='minimum support value',
default=0.15,
type='float')
optparser.add_option('-c', '--minConfidence',
dest='minC',
help='minimum confidence value',
default=0.6,
type='float')
(options, args) = optparser.parse_args()
inFile = None
if options.input is None:
inFile = sys.stdin
elif options.input is not None:
inFile = dataFromFile(options.input)
else:
print 'No dataset filename specified, system with exit\n'
sys.exit('System will exit')
minSupport = options.minS
minConfidence = options.minC
items, rules = runApriori(inFile, minSupport, minConfidence)
printResults(items, rules)
Was ist der "Titel des Tupels"? Ein Tupel ist das: '(1,2)' - wie lautet der Titel? –
Angenommen, ich habe eine Tabelle in cvs die erste Zeile enthält die Attributnamen. Ich möchte diese Attributnamen extrahieren.Pardon mein schlechtes Englisch –