def naiveBayes(features, sc, output_n):
''' calling NaiveBayes with and training using our data set '''
features_and_label = features.collect()
training_features_labels = features_and_label[0:70]
testing_features_labels = features_and_label[70:116]
labeled_training = []
for x in training_features_labels:
labeled_training.append(LabeledPoint(x[0], x[1]))
naivebayes_model = NaiveBayes.train(sc.parallelize(labeled_training), 1.0)
predictions = []
for efeature in testing_features_labels:
testing_data = LabeledPoint(efeature[0], efeature[1])
prediction = naivebayes_model.predict(testing_data.features)
predictions.append([testing_data.label, float(prediction)])
labeled_training.append(testing_data)
naivebayes_model = NaiveBayes.train(sc.parallelize(labeled_training),
1.0)
return naivebayes_model, predictions
def SA_training(input_filename):
# Import full dataset of newsgroup posts as text file
rdd = SC.textFile(input_filename)
rdd = rdd.map(lambda line: line.split(","))
HEADER = rdd.take(1)[0]
# Remove the header from the rdd
rdd = rdd.filter(lambda line: line != HEADER and len(line) >= 4)
# Fix tweet if it contained "," and removed while splitting
rdd = rdd.map(lambda line: line_fixer(line, len(HEADER)))
# Return only the label and the tweet and ignore other columns.
# now rddd example [[1,"This is the first positive tweet"], [0, "This is the first negative tweet"]]
rdd = rdd.map(remove_unwanted_col)
rdd = pre_process(rdd)
get_word_ratio(rdd, word="happy")
data_hashed = rdd.map(lambda (sentiment, tweet): LabeledPoint(sentiment, HTF.transform(tweet)))
train_hashed, test_hashed = data_hashed.randomSplit([0.7, 0.3])
model = NaiveBayes.train(train_hashed, lambda_=7.0)
prediction_and_labels = test_hashed.map(lambda point: (model.predict(point.features), point.label))
correct = prediction_and_labels.filter(lambda (predicted, actual): predicted == actual)
accuracy = correct.count() / float(test_hashed.count())
logger.info("Naive Bayes correctly classified the tweets with an accuracy of " + str(accuracy * 100) + "%.")
return model
def nBayes(resultsDict, Lambda=1.0):
start = time()
nbModel = NaiveBayes.train(trainSetLP[j], Lambda)
ET = time() - start
# Classify all sets (validation, training and test) using the model, and pass results
# to the rMetrics function so they are added to results summary dict
startClassify = time()
start = time()
validPredict = validSet[j].map(lambda (lbl, vec):
((lbl, nbModel.predict(vec)), 1))
validResults = validPredict.reduceByKey(add).collectAsMap()
EC = time() - start
rMetrics("NBay", Lambda, "Validation", validResults, resultsDict, ET, EC)
start = time()
trainPredict = trainSet[j].map(lambda (lbl, vec):
((lbl, nbModel.predict(vec)), 1))
trainResults = trainPredict.reduceByKey(add).collectAsMap()
EC = time() - start
rMetrics("NBay", Lambda, "Training", trainResults, resultsDict, ET, EC)
start = time()
testPredict = testSet.map(lambda (lbl, vec):
((lbl, nbModel.predict(vec)), 1))
testResults = testPredict.reduceByKey(add).collectAsMap()
EC = time() - start
rMetrics("NBay", Lambda, "Test", testResults, resultsDict, ET, EC)
print "; Training:", '{:.2f}s'.format(ET), "; Classification:", \
'{:.2f}s'.format(time() - startClassify)
def calc_naive_bayes_using_pyspark(training_data, num_partitions=20):
"""
Determine the predicted rating of every user-item combination using MLlib's Naive Bayes algorithm.
Args:
training_data: the data used to train the RecSys algorithm in the format of a RDD of [ (userId, itemId, actualRating) ]
Returns:
predictions: predicted ratings of every user-item combination in the format of a RDD of [(userId, itemId, predictedRating)].
"""
# to use MLlib's Naive Bayes model, it requires the input to be in a format of a LabeledPoint
# therefore, convert dataset so that it will in the format [(rating, (user, item))]
r_ui_train = training_data.map(lambda (u, i, r): LabeledPoint(r, (u, i)))
# train Naive Bayes model
naiveBayesModel = NaiveBayes.train(r_ui_train, lambda_=1.0)
# predict on all user-item pairs
user_ids = training_data.map(lambda (u, i, r): u).distinct()
item_ids = training_data.map(lambda (u, i, r): i).distinct()
ui_combo = user_ids.cartesian(item_ids).coalesce(num_partitions)
r_ui_combo = ui_combo.map(lambda (u, i, r): LabeledPoint(1, (u, i)))
# make prediction
predictions = r_ui_combo.map(lambda p: (p.features[0], p.features[
1], naiveBayesModel.predict(p.features)))
return predictions
def do_nb():
sc = SparkContext("local[*]", "NB")
fi = LineFile("./data.txt")
rawdata = []
for line in fi:
item = map(lambda x: str(x), line.split(","))
rawdata.append((int(item[0]), map(float, item[2:])))
def make_labeled(record):
return LabeledPoint(record[0], Vectors.dense(record[1]))
dataset = sc.parallelize(rawdata).map(make_labeled)
[trset, vlset, tsset] = split_dataset(dataset)
model = NaiveBayes.train(trset, 1.0)
predictionAndLabel = tsset.map(lambda p:
(model.predict(p.features), p.label))
accuracy = 1.0 * predictionAndLabel.filter(
lambda (x, v): x == v).count() / tsset.count()
print accuracy
for x in predictionAndLabel.collect():
print x
def test_classification(self):
from pyspark.mllib.classification import LogisticRegressionWithSGD, SVMWithSGD, NaiveBayes
data = [
LabeledPoint(0.0, self.scipy_matrix(2, {0: 1.0})),
LabeledPoint(1.0, self.scipy_matrix(2, {1: 1.0})),
LabeledPoint(0.0, self.scipy_matrix(2, {0: 2.0})),
LabeledPoint(1.0, self.scipy_matrix(2, {1: 2.0}))
]
rdd = self.sc.parallelize(data)
features = [p.features for p in data]
lr_model = LogisticRegressionWithSGD.train(rdd)
self.assertTrue(lr_model.predict(features[0]) <= 0)
self.assertTrue(lr_model.predict(features[1]) > 0)
self.assertTrue(lr_model.predict(features[2]) <= 0)
self.assertTrue(lr_model.predict(features[3]) > 0)
svm_model = SVMWithSGD.train(rdd)
self.assertTrue(svm_model.predict(features[0]) <= 0)
self.assertTrue(svm_model.predict(features[1]) > 0)
self.assertTrue(svm_model.predict(features[2]) <= 0)
self.assertTrue(svm_model.predict(features[3]) > 0)
nb_model = NaiveBayes.train(rdd)
self.assertTrue(nb_model.predict(features[0]) <= 0)
self.assertTrue(nb_model.predict(features[1]) > 0)
self.assertTrue(nb_model.predict(features[2]) <= 0)
self.assertTrue(nb_model.predict(features[3]) > 0)
def trainAndTestNB(train_lbl_vec, test_lbl_vec, lastTime):
# create LabeledPoints for training
lblPnt = train_lbl_vec.map(lambda (x, l): LabeledPoint(x, l))
#print lblPnt.collect()
# train the model
model = NaiveBayes.train(lblPnt, 1.0)
# evaluate training
resultsTrain = train_lbl_vec.map(lambda lp:
(lp.label, model.predict(lp.features)))
resultMap = resultsTrain.countByValue()
# print 'TRAIN '
trainAccuracy = accuracy(resultMap)
# test the model
data = test_lbl_vec.map(lambda (x, l): LabeledPoint(x, l))
resultsTest = data.map(lambda lp: (lp.label, model.predict(lp.features)))
resultMapTest = resultsTest.countByValue()
#print 'TEST '
testAccuracy = accuracy(resultMapTest)
thisTime = time()
elapsedTime = thisTime - lastTime
return [elapsedTime, trainAccuracy, testAccuracy]
def create_model_text(self, data, params):
lambda_ = float(params.get('lambda', 1.0))
points = self.parseTextRDDToIndex(data)
return NaiveBayes.train(points, lambda_)
def model_run_NaiveBayes(sc, HashSize, Subject, trainingData, testingData):
print "TRAINING NAIVE BAYES"
start_time = time()
fileNum = trainingData.count()
# create the LabeledPoint
trainingLP = trainingData.map(lambda (x, l): LabeledPoint(x, l))
# Train the model
nbModel = NaiveBayes.train(trainingLP, 1.0)
resultsTrain = trainingData.map(lambda (l, v):
((l, nbModel.predict(v)), 1))
resultsTrain = resultsTrain.reduceByKey(add)
resultMap = resultsTrain.collectAsMap()
printMetrics("Training", HashSize, Subject, resultMap, fileNum,
time() - start_time, 'True')
print ""
print 'TEST RESULTS'
start_time = time()
fileNum = testingData.count()
resultsTest = testingData.map(
lambda (l, v): ((l, nbModel.predict(v)), 1)).reduceByKey(add)
resultMapTest = resultsTest.collectAsMap()
printMetrics("Testing", HashSize, Subject, resultMapTest, fileNum,
time() - start_time, 'True')
def do_training(para=1.0):
with open('H2_15300180012_output.txt', 'a') as f:
f.write('Naive Bayes parameter: {} \n'.format(para))
# Train a naive Bayes model.
model = NaiveBayes.train(train, para)
# train accuracy.
predictionAndLabel = train.map(lambda p:
(model.predict(p.features), p.label))
accuracy = 1.0 * predictionAndLabel.filter(
lambda pl: pl[0] == pl[1]).count() / train.count()
with open('H2_15300180012_output.txt', 'a') as f:
f.write('training accuracy: {} \n'.format(accuracy))
# print 'model accuracy {}'.format(accuracy)
# validation accuracy.
predictionAndLabel = val.map(lambda p:
(model.predict(p.features), p.label))
accuracy = 1.0 * predictionAndLabel.filter(
lambda pl: pl[0] == pl[1]).count() / val.count()
with open('H2_15300180012_output.txt', 'a') as f:
f.write('validation accuracy: {} \n'.format(accuracy))
# print 'model accuracy {}'.format(accuracy)
# test accuracy.
predictionAndLabel = test.map(lambda p:
(model.predict(p.features), p.label))
accuracy = 1.0 * predictionAndLabel.filter(
lambda pl: pl[0] == pl[1]).count() / test.count()
with open('H2_15300180012_output.txt', 'a') as f:
f.write('test accuracy: {} \n'.format(accuracy))
def trainModel(self, vectSpace, path):
try:
if self.type == 'NaiveBayes':
model = NaiveBayes.train(vectSpace)
elif self.type == 'DecisionTree':
model = DecisionTree.trainClassifier(
vectSpace,
numClasses=len(self.category),
categoricalFeaturesInfo={},
impurity='gini',
maxDepth=5,
maxBins=5)
if not os.path.exists(path):
os.makedirs(path)
else:
shutil.rmtree(path)
os.makedirs(path)
model.save(self.sc, path)
except:
print "Unexpected error:", sys.exc_info()[0]
raise
return model
def test_classification(self):
from pyspark.mllib.classification import LogisticRegressionWithSGD, SVMWithSGD, NaiveBayes
data = [
LabeledPoint(0.0, [1, 0, 0]),
LabeledPoint(1.0, [0, 1, 1]),
LabeledPoint(0.0, [2, 0, 0]),
LabeledPoint(1.0, [0, 2, 1])
]
rdd = self.sc.parallelize(data)
features = [p.features.tolist() for p in data]
lr_model = LogisticRegressionWithSGD.train(rdd)
self.assertTrue(lr_model.predict(features[0]) <= 0)
self.assertTrue(lr_model.predict(features[1]) > 0)
self.assertTrue(lr_model.predict(features[2]) <= 0)
self.assertTrue(lr_model.predict(features[3]) > 0)
svm_model = SVMWithSGD.train(rdd)
self.assertTrue(svm_model.predict(features[0]) <= 0)
self.assertTrue(svm_model.predict(features[1]) > 0)
self.assertTrue(svm_model.predict(features[2]) <= 0)
self.assertTrue(svm_model.predict(features[3]) > 0)
nb_model = NaiveBayes.train(rdd)
self.assertTrue(nb_model.predict(features[0]) <= 0)
self.assertTrue(nb_model.predict(features[1]) > 0)
self.assertTrue(nb_model.predict(features[2]) <= 0)
self.assertTrue(nb_model.predict(features[3]) > 0)
def modelWithNaiveBayes(trainingData, validationData):
##Train the model using Naive Bayes with different values for the regularization parameter lambda.
##Return the Naive Bayes model with best accuracy rate
regularizationParamater = [.000000001, .0005, 1., 100000., 2000000.]
bestNaiveBayesModel = None
bestAccuracy = 0
visualizationData = []
for regularizer in regularizationParamater:
model = NaiveBayes.train(trainingData, regularizer)
predict = validationData.map(lambda ad:
(ad.label, model.predict(ad.features)))
totalValidationAds = validationData.count()
correctlyPredicted = predict.filter(lambda x: x[0] == x[1]).count()
accuracy = float(correctlyPredicted) / totalValidationAds
##Record the accuracy of this model for different values of lambda (the regularization parameter)
visualizationData += [(regularizer, accuracy)]
if accuracy > bestAccuracy:
bestAccuracy = accuracy
bestNaiveBayesModel = model
return bestNaiveBayesModel, visualizationData
def naive_bayes_module(training):
"""This function returns a naive bayes model from your training data.
Parameter:
training (REQUIRED) - the training data
"""
# Train a Naive Bayes model
return NaiveBayes.train(training)
def trainEvaluateModel(trainData, validationData, lambdaParam):
startTime = time()
model = NaiveBayes.train(trainData, lambdaParam)
AUC = evaluateModel(model, validationData)
duration = time() - startTime
print("训练评估：lambdaParam->", lambdaParam)
print("==> 所需时间:", duration, "s ,AUC=", AUC)
return (AUC, duration, lambdaParam, model)
def train(cls, data, s_lambda=1.0):
"""
@data, LabeledPoint组成RDD
@s_lambda, 平均指数,默认拉普拉斯平滑(s_lambda=1.0)
"""
first = data.first()
assert isinstance(first, LabeledPoint), "data, LabeledPoint组成RDD"
return NaiveBayes.train(data, s_lambda)
def create_bayes(self):
""" 创建贝叶斯训练模型 """
if self._check_traning_exists():
return
# 获取积极文本构造rdd
positive_file = os.path.join(settings.DATA_DIR, '分类词库/positive.txt')
positive_data = self.sc.textFile(positive_file)
# 数据去重
positive_data = positive_data.distinct()
positive_data = positive_data.map(
lambda line: line.split('###')).filter(lambda line: len(line) == 2)
# 获取消极文本构造rdd
negative_file = os.path.join(settings.DATA_DIR, '分类词库/negative.txt')
negative_data = self.sc.textFile(negative_file)
negative_data = negative_data.distinct()
negative_data = negative_data.map(
lambda line: line.split('###')).filter(lambda line: len(line) == 2)
# 合并训练集
all_data = negative_data.union(positive_data)
all_data.repartition(1)
# 评分已经提前进行处理只有-1与1
rate = all_data.map(lambda s: s[0])
document = all_data.map(lambda s: s[1])
words = document.map(lambda w:"/".\
join(jieba.cut_for_search(w))).\
map(lambda line: line.split("/"))
# 训练词频矩阵
hashingTF = HashingTF()
tf = hashingTF.transform(words)
# 计算TF-IDF矩阵
idfModel = IDF().fit(tf)
tfidf = idfModel.transform(tf)
tf.cache()
# 生成训练集和测试集
zipped = rate.zip(tfidf)
data = zipped.map(lambda line: LabeledPoint(line[0], line[1]))
training, test = data.randomSplit([0.6, 0.4], seed=0)
# 训练贝叶斯分类模型
NBmodel = NaiveBayes.train(training, 1.0)
predictionAndLabel = test.map(lambda p:
(NBmodel.predict(p.features), p.label))
accuracy = 1.0 * predictionAndLabel.filter(lambda x: 1.0 \
if x[0] == x[1] else 0.0).count() / test.count()
# 存储rdd
words.repartition(1).saveAsTextFile(self.training_words_dir)
# 贝叶斯分类模型以pickle存储
with open(self.NBmodel, 'w') as f:
pickle.dump(NBmodel, f)
def loadClassifierModel(self):
train_list = list()
# 0,评分
scoreQuestions = self.loadFile("./chatBot/question/【0】评分.txt")
sentences = scoreQuestions.split("`")
for sentence in sentences:
array = self.sentenceToVector(sentence)
train_one = LabeledPoint('0.0', Vectors.dense(array))
train_list.append(train_one)
# 1,类型
scoreQuestions = self.loadFile("./chatBot/question/【1】类型.txt")
sentences = scoreQuestions.split("`")
for sentence in sentences:
array = self.sentenceToVector(sentence)
train_one = LabeledPoint('1.0', Vectors.dense(array))
train_list.append(train_one)
# 2,信息
scoreQuestions = self.loadFile("./chatBot/question/【2】菜品信息.txt")
sentences = scoreQuestions.split("`")
for sentence in sentences:
array = self.sentenceToVector(sentence)
train_one = LabeledPoint('2.0', Vectors.dense(array))
train_list.append(train_one)
# 3,价格
scoreQuestions = self.loadFile("./chatBot/question/【3】菜的价格.txt")
sentences = scoreQuestions.split("`")
for sentence in sentences:
array = self.sentenceToVector(sentence)
train_one = LabeledPoint('3.0', Vectors.dense(array))
train_list.append(train_one)
# 4,加入点餐列表
scoreQuestions = self.loadFile("./chatBot/question/【4】加入菜单.txt")
sentences = scoreQuestions.split("`")
for sentence in sentences:
array = self.sentenceToVector(sentence)
train_one = LabeledPoint('4.0', Vectors.dense(array))
train_list.append(train_one)
# 5,移除菜单
scoreQuestions = self.loadFile("./chatBot/question/【5】移除菜单.txt")
sentences = scoreQuestions.split("`")
for sentence in sentences:
array = self.sentenceToVector(sentence)
train_one = LabeledPoint('5.0', Vectors.dense(array))
train_list.append(train_one)
conf = SparkConf().setAppName('NaiveBayesTest').setMaster('local[*]')
sc = SparkContext(conf=conf)
distData = sc.parallelize(train_list, numSlices=10)
nb_model = NaiveBayes.train(distData)
return nb_model
def train_evaluate_model(train_data, valid_data, lambda_):
start_time = time()
# 训练
model = NaiveBayes.train(train_data, lambda_)
# 评估
# y_pred y_true
AUC = evaluate_model(model, valid_data)
duration = time() - start_time
print(f"训练评估：使用参数 lambda_={lambda_} ==>所需时间={duration} 结果AUC = {AUC}")
return AUC, duration, lambda_, model
def trainEvaluateModel(trainData,validationData,lambdaParam):
startTime = time()
model = NaiveBayes.train(trainData, lambdaParam)
AUC = evaluateModel(model, validationData)
duration = time() - startTime
print "训练评估：使用参数" + \
" lambda="+str( lambdaParam) +\
" 所需时间="+str(duration) + \
" 结果AUC = " + str(AUC)
return (AUC,duration, lambdaParam,model)
def trainEvaluationModel(trainData, validationData, lambdaParam):
startTime = time()
# lambda 设置lambda参数，默认值为1.0
model = NaiveBayes.train(trainData, lambdaParam)
AUC = evaluateModel(model, validationData)
duration = time() - startTime
print("训练评估：使用参数 " + \
" lambda = " + str(lambdaParam) + \
" ==> 所需时间 = " + str(duration) + " 秒"\
" 结果 AUC = " + str(AUC))
return AUC, duration, lambdaParam, model
def main(sc, argv):
#read the filter tweets from file
tweets_rdd = sc.textFile(INPUT_LABEL_TWEETS_DATA_PATH)
# Create an RDD of LabeledPoints using category labels as labels and tokenized, hashed text as feature vectors
features_hashed = tweets_rdd.map(generatedHashedFeatures)
# persist the RDD so it won't have to be re-created later
features_hashed.persist()
#randomly split the data into test and training data
training_data, testing_data = features_hashed.randomSplit([0.7, 0.3])
#finally train a naive bayes model
naivebayes_model = NaiveBayes.train(training_data)
def test_classification(self):
from pyspark.mllib.classification import LogisticRegressionWithSGD, SVMWithSGD, NaiveBayes
from pyspark.mllib.tree import DecisionTree, RandomForest, GradientBoostedTrees
data = [
LabeledPoint(0.0, [1, 0, 0]),
LabeledPoint(1.0, [0, 1, 1]),
LabeledPoint(0.0, [2, 0, 0]),
LabeledPoint(1.0, [0, 2, 1])
]
rdd = self.sc.parallelize(data)
features = [p.features.tolist() for p in data]
lr_model = LogisticRegressionWithSGD.train(rdd)
self.assertTrue(lr_model.predict(features[0]) <= 0)
self.assertTrue(lr_model.predict(features[1]) > 0)
self.assertTrue(lr_model.predict(features[2]) <= 0)
self.assertTrue(lr_model.predict(features[3]) > 0)
svm_model = SVMWithSGD.train(rdd)
self.assertTrue(svm_model.predict(features[0]) <= 0)
self.assertTrue(svm_model.predict(features[1]) > 0)
self.assertTrue(svm_model.predict(features[2]) <= 0)
self.assertTrue(svm_model.predict(features[3]) > 0)
nb_model = NaiveBayes.train(rdd)
self.assertTrue(nb_model.predict(features[0]) <= 0)
self.assertTrue(nb_model.predict(features[1]) > 0)
self.assertTrue(nb_model.predict(features[2]) <= 0)
self.assertTrue(nb_model.predict(features[3]) > 0)
categoricalFeaturesInfo = {0: 3} # feature 0 has 3 categories
dt_model = DecisionTree.trainClassifier(
rdd, numClasses=2, categoricalFeaturesInfo=categoricalFeaturesInfo)
self.assertTrue(dt_model.predict(features[0]) <= 0)
self.assertTrue(dt_model.predict(features[1]) > 0)
self.assertTrue(dt_model.predict(features[2]) <= 0)
self.assertTrue(dt_model.predict(features[3]) > 0)
rf_model = RandomForest.trainClassifier(
rdd,
numClasses=2,
categoricalFeaturesInfo=categoricalFeaturesInfo,
numTrees=100)
self.assertTrue(rf_model.predict(features[0]) <= 0)
self.assertTrue(rf_model.predict(features[1]) > 0)
self.assertTrue(rf_model.predict(features[2]) <= 0)
self.assertTrue(rf_model.predict(features[3]) > 0)
gbt_model = GradientBoostedTrees.trainClassifier(
rdd, categoricalFeaturesInfo=categoricalFeaturesInfo)
self.assertTrue(gbt_model.predict(features[0]) <= 0)
self.assertTrue(gbt_model.predict(features[1]) > 0)
self.assertTrue(gbt_model.predict(features[2]) <= 0)
self.assertTrue(gbt_model.predict(features[3]) > 0)
def ml_features_normal(self, features):
from pyspark.ml.linalg import Vectors
from pyspark.ml.feature import Normalizer
from pyspark.ml.classification import NaiveBayes
from tools import f
features.foreach(print)
fea_df = features.map(lambda i: Row(**f(i))).toDF()
# fea_df.show()
normalizer = Normalizer().setInputCol('features').setOutputCol(
'norfeatures').setP(1.0)
norfea_df = normalizer.transform(fea_df)
# norfea_df.show()
train_dt, test_dt = norfea_df.randomSplit([0.8, 0.2])
nvby = NaiveBayes(modelType="multinomial", smoothing=0.1)
nvby_mod = nvby.fit(dataset=train_dt)
predictRDD = nvby_mod.transform(test_dt).rdd
count = predictRDD.count()
print(
predictRDD.map(lambda i: (i.label, i.prediction)).filter(
lambda i: i[0] == i[1]).count() / count)
def process(reviews):
if (reviews.isEmpty()):
pass
else:
start = time.time()
#get reviews with overall rating > 3 and overall rating < 3
pos_reviews = reviews.filter(lambda x: x[0] > 3.0)
neg_reviews = reviews.filter(lambda x: x[0] < 3.0)
#set label for each class. 0.0 is positive - 1.0 is negative
review_labels = reviews.map(lambda x: 0.0 if x[0] > 3.0 else 1.0)
Words = Row('label', 'words')
words = reviews.map(lambda r: Words(*r))
words_df = spark.createDataFrame(words)
#reviews tokenization
token = RegexTokenizer(minTokenLength=2,
pattern="[^A-Za-z]+",
inputCol="words",
outputCol="token",
toLowercase=True)
token_filtered = token.transform(words_df)
#stopwords elimination
remover = StopWordsRemover(inputCol="token",
outputCol="stopwords",
caseSensitive=False)
stopwords_filtered = remover.transform(token_filtered)
prep_filtered = (
stopwords_filtered.select('stopwords').rdd).map(lambda x: x[0])
#tf-idf calculation
tf = HashingTF(numFeatures=numFeatures).transform(
prep_filtered.map(porter_stem, preservesPartitioning=True))
idf = IDF().fit(tf)
train_tfidf = idf.transform(tf)
#set training dataset with label
training = review_labels.zip(train_tfidf).map(
lambda x: LabeledPoint(x[0], x[1]))
#train the model classifier
model = NaiveBayes.train(training)
#save model classifier to HDFS
output_dir = "hdfs://VM10-1-0-14:9000/classifier/" + model_name
model.save(sc, output_dir)
end = time.time()
print("Total Reviews : ", reviews.count(), "Processing Time : ",
(end - start))
ssc.stop()
def NB_train(data):
data_train = split_data(data)
# data_train,data_cv = data.randomSplit([0.8,0.2],0)
key_FT = data_train.map(lambda x: LabeledPoint(x[1], x[-1]))
training, test = key_FT.randomSplit([0.8, 0.2], 0)
model_NB = NaiveBayes.train(training, 0.1)
predictionAndlabel = test.map(
lambda x: (float(model_NB.predict(x.features)), x.label))
accuracy = 1.0 * predictionAndlabel.filter(
lambda (x, v): x == v).count() / test.count()
print("accuracy of model_NB:%f" % accuracy)
return model_NB, accuracy
def predict_NaiveBayes(lamb):
"""
NaiveBayes.train(data, lambda=1.0)
data: the training data of RDD of LabeledPoint
lambda: the smoothing parameter, default 1.0
"""
naiveBayesModel = NaiveBayes.train(scaledData, lamb)
naiveBayesMetrics = scaledData.map(
lambda p: (p.label, naiveBayesModel.predict(p.features)))
naiveBayesAccuracy = naiveBayesMetrics.filter(
lambda (actual, pred): actual == pred).count() * 1.0 / data.count()
return naiveBayesAccuracy
def train():
sc = SparkContext(appName= 'nb_test')
data = sc.textFile('../dat/^HSI-^DJI_^FCHI_^FVX_^FTSE_VNQ_QQQ_GOOG_BAC-').map(parseLine)
# Split data aproximately into training (60%) and test (40%)
training, test = data.randomSplit([0.7, 0.3], seed=0)
print training.collect()
# Train a naive Bayes model.
model = NaiveBayes.train(training, 1.0) #, "bernoulli")
predictionAndLabel = test.map(lambda p: (model.predict(p.features), p.label))
accuracy = 1.0 * predictionAndLabel.filter(lambda (x, v): x == v).count() / test.count()
print '**** ACCURACY', accuracy
def RunNaiveBayes(tf): rdd = tf.map(parseAsNonNegativeLabeledPoint) train, test = rdd.randomSplit([.8, .2]) model = NaiveBayes.train(train, 1.0) predictionAndLabel = test.map(lambda p: (model.predict(p.features), p.label)) accuracy = 1.0 * predictionAndLabel.filter(lambda (x, v): x == v).count() / test.count() # Save and load model #model.save(sc, "target/tmp/myNaiveBayesModel") #sameModel = NaiveBayesModel.load(sc, "target/tmp/myNaiveBayesModel") print 'Accuracy of Logit = ', accuracy * 100 print "Test Error = ", (1.0 - accuracy) * 100
def NaiveBayes_classification(training, test):
print "\n\n-----------------------------------------------------------------------------"
print " Naive Bayes"
print "-----------------------------------------------------------------------------\n\n"
# Train a naive Bayes model.
model = NaiveBayes.train(training, 1.0)
# Make prediction and test accuracy.
predictionAndLabel = test.map(lambda p:
(model.predict(p.features), p.label))
accuracy = 1.0 * predictionAndLabel.filter(
lambda pl: pl[0] == pl[1]).count() / test.count()
print('model accuracy {}'.format(accuracy))
