text = '"Go until jurong point, crazy.. Available only in bugis n great world la e buffet... Cine there got amore wat..."'
import nltk
from nltk.corpus import stopwords
from nltk.stem import WordNetLemmatizer
nltk.download()
#预处理
def preprocessing(text):
#text = text.decode("utf-8)
tokens = [word for sent in nltk.sent_tokenize(text) for word in nltk.word_tokenize(sent)]
stops = stopwords.words('english')
tokens = [token for token in tokens if token not in stops]
tokens = [token.lower() for token in tokens if len(token)>=3]
lmtzr = WordNetLemmatizer()
tokens = [lmtzr.lenmatize(token) for token in tokens]
preprocessed_text = ' '.join(tokens)
return preprocessed_text
preprocessing(text)
import csv #用csv读取邮件数据,分解出邮件类别及邮件内容
file_path = r'C:UsersAdministratorDesktopSMSSpamCollectionjsn.txt'
sms = open(file_path,'r',encoding = 'utf-8')
sms_data = []
sms_label = []
csv_reader = csv.reader(sms,delimiter=' ')
for line in csv_reader:
sms_label.append(line[0])
sms_data.append(processing[1])
sms.close()
sms_label
sms_data
from sklearn.model_selection import train_test_split
x_train,x_test,y_train,y_test = train_test_split(sms_data,sms_label,test_size=0.3,random_state=0,stratify=sms_label) #训练集,测试集
#将其向量化
from sklearn.feature_extraction.text import TfidfVectorizer
vectorizer = TfidfVectorizer(min_df = 2,ngram_range=(1,2),stop_words='english',strip_accents='unicode',norm='l2')
x_train = vectorizer.fit_transform(x_train)
x_test = vectorizer.transform(x_test)
#朴素贝叶斯分类器
from sklearn.naive_bayes import MultinomialNB
clf = MultinomialNB().fit(x_train,y_train)
y_nb_pred = clf.predict(x_test)
#分类结果显示
from sklearn.metrics import confusion_matrix
from sklearn.metrics import classification_report
print(y_nb_pred.shape,y_nb_pred) #x_text预测结果
print('nb_confusion_matrix:')
cm = confusion.matrix(y_test,y_nb_pred) #混淆矩阵
print(cm)
print('nb_classification_report')
cr = classification_report(y_test,y_nb_pred) #主要分类指标的文本报告
print(cr)
feature_name = vectorizer.get_feature_name() #出现过的单词列表
coefs = clf.coef_ #先验证概率
intercept = clf.intercept_
coef_with_fns = sorted(zip(coefs[0],feature_names)) #对数概率p(x_i)y与单词x_i映射
n=10
top = zip(coefs_with_fns[:n],coefs_with_fns[:(n+1):-1])
for(coef_1,fn_1),(coef_2,fn_2) in top:
print('')
text='"As per your request Melle Melle Oru Minnaminunginte Nurungu Vettam has been set as your callertune for all Callers. Press *9 to copy your friends Callertune"'
import nltk #nltk进行分词
for sent in nltk.sent_tokenize(text): #对文本按照句子进行分割
for word in nltk.word_tokenize(sent): #对句子进行分词
print(word)
tokens = [word for sent in nltk.sent_tokenize(text) for word in nltk.word_tokenize(sent)]
from nltk.corpus import stopwords #去掉停用词
stops = stopwords.words('english')
stops
tokens = [token for token in tokens if token not in stops]
s = set(tokens)-set(stops)
print(len(tokens),len(set(tokens)),len(s))
# nltk.download('wordnet')
from nltk.stem import WordNetLemmatizer #词性还原
lemmatizer = WordNetLemmatizer()
lemmatizer.lemmatize('leavers')
import csv # 读数据 file_path = r'EmailData.txt' EmailData = open(file_path,'r',encoding='utf-8') Email_data = [] Email_target = [] csv_reader = csv.reader(EmailData,delimiter=' ') # 将数据分别存入数据列表和目标分类列表 for line in csv_reader: Email_data.append(line[1]) Email_target.append(line[0]) EmailData.close() # 把无意义的符号都替换成空格 Email_data_clear = [] for line in Email_data: # line :'Go until jurong point, crazy.. Available only in bugis n great world la e buffet...' # 每一行都去掉无意义符号并按空格分词 for char in line: if char.isalpha() is False: # 不是字母,发生替换操作: newString = line.replace(char," ") tempList = newString.split(" ") # 将处理好后的一行数据追加到存放干净数据的列表 Email_data_clear.append(tempList) # 去掉长度不大于3的词和没有语义的词 Email_data_clear2 = [] for line in Email_data_clear: tempList = [] for word in line: if word != '' and len(word) > 3 and word.isalpha(): tempList.append(word) tempString = ' '.join(tempList) Email_data_clear2.append(tempString) Email_data_clear = Email_data_clear2 # 将数据分为训练集和测试集 from sklearn.model_selection import train_test_split x_train,x_test,y_train,y_test = train_test_split(Email_data_clear2,Email_target,test_size=0.3,random_state=0,stratify=Email_target) # 建立数据的特征向量 from sklearn.feature_extraction.text import TfidfVectorizer tfidf = TfidfVectorizer() X_train = tfidf.fit_transform(x_train) X_test = tfidf.transform(x_test) # 观察向量 import numpy as np X_train = X_train.toarray() X_test = X_test.toarray() X_train.shape # 输出不为0的列 for i in range(X_train.shape[0]): for j in range(X_train.shape[1]): if X_train[i][j] != 0: print(i,j,X_train[i][j]) # 建立模型 from sklearn.naive_bayes import GaussianNB gnb = GaussianNB() module = gnb.fit(X_train,y_train) y_predict = module.predict(X_test) # 输出模型分类的各个指标 from sklearn.metrics import classification_report cr = classification_report(y_predict,y_test) print(cr)