Exemple #1
0
def naivebayes_mllib():
    AWS_ACCESS_KEY_ID = "XXXXXXXXXXXXXXXXXX"
    AWS_SECRET_ACCESS_KEY = "XXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXXX"

    sc._jsc.hadoopConfiguration().set("fs.s3n.awsAccessKeyId", AWS_ACCESS_KEY_ID)
    sc._jsc.hadoopConfiguration().set("fs.s3n.awsSecretAccessKey", AWS_SECRET_ACCESS_KEY)

    tr_folder = "s3n://usf-ml2/hwspark/train/"
    tr_neg_path = tr_folder+ "neg/*.txt"
    neg_files = sc.textFile(tr_neg_path)
    neg = neg_files.map(lambda x: parsedoc(x))
    neg = neg.map(lambda x: x.replace(',',' ').replace('.', ' ').replace('-',' ').lower())
    neg1= neg.flatMap(lambda x:x.split())
    neg1 = neg1.map(lambda x: removeStopWords(x))
    tf = HashingTF().transform(neg1.map(lambda x: x, preservesPartitioning=True))
    neg_tr = tf.map(lambda x: LabeledPoint(0.0, x))

    tr_pos_path = tr_folder+ "pos/*.txt"
    pos_files = sc.textFile(tr_pos_path)
    pos = pos_files.map(lambda x: x.replace(',',' ').replace('.', ' ').replace('-',' ').lower())
    pos = pos.map(lambda x: parsedoc(x))
    pos1= pos.flatMap(lambda x:x.split())
    pos1 = pos1.map(lambda x: removeStopWords(x))
    tf_pos = HashingTF().transform(pos1.map(lambda x: x, preservesPartitioning=True))
    pos_tr = tf_pos.map(lambda x: LabeledPoint(1.0, x))

    training = neg_tr.union(pos_tr)
    model = NaiveBayes.train(training)
    te_folder = "s3n://usf-ml2/hw_spark/test/"
    test_Npath = te_folder+"neg/*.txt"
    test_Ppath = te_folder+ "pos/*.txt"
    test = sc.textFile(test_Npath)
    test_p = sc.textFile(test_Ppath)

    test = test.map(lambda x: parsedoc(x))
    test2= test.flatMap(lambda x:x.split())
    test1 = test2.map(lambda x: x.replace(',',' ').replace('.', ' ').replace('-',' ').lower())
    test2 = test1.map(lambda x: removeStopWords(x))
    tf1 = HashingTF().transform(test2.map(lambda x: x, preservesPartitioning=True))

    test5 = tf1.map(lambda x: LabeledPoint(0.0, x))

    test_p = test_p.map(lambda x: parsedoc(x))
    test_p1 = test_p.map(lambda x: x.replace(',',' ').replace('.', ' ').replace('-',' ').lower())
    test_p2= test_p1.flatMap(lambda x:x.split())
    test_p2 = test_p2.map(lambda x: removeStopWords(x))
    tf_p1 = HashingTF().transform(test_p2.map(lambda x: x, preservesPartitioning=True))

    test_p5 = tf_p1.map(lambda x: LabeledPoint(1.0, x))
    testpn = test5.union(test_p5)
    predictionAndLabel = testpn.map(lambda p: (model.predict(p.features), p.label))
    accuracy = predictionAndLabel.filter(lambda (x, v): x == v).count()*1.0 /float(test2.count()+test_p2.count())
    print "Accuracy is {}".format(round(accuracy,5))
def create_labelPoints(rawdata, label):
    tf = HashingTF().transform(
        rawdata.map(lambda doc: doc[1].lower().split(" "), preservesPartitioning=True))
    return(tf.map(lambda x: LabeledPoint(label, x)))