from sklearn.naive_bayes import BernoulliNB,MultinomialNB from sklearn.feature_extraction.text import CountVectorizer from sklearn.model_selection import train_test_split import pandas as pd path = 'E:/Python_file/zuoye/SMSSpamCollection.txt' Cnames=['labels','messages'] data = pd.read_csv(path,sep='\t', header=None, names=Cnames) #读取数据集，分隔符是\t data=data.replace({'ham':0,'spam':1}) #替换标签值 print('数据集展示：') print(data) print('\n----------------------------------\n') X=data['messages'] y=data['labels'] x_train,x_test,y_train,y_test=train_test_split(X,y,train_size=0.8,random_state=123) vector_nomial=CountVectorizer() #实现词袋模型 vector_bernou=CountVectorizer() #多项式模型分类垃圾短信 train_matrix=vector_nomial.fit_transform(x_train) test_matrix=vector_nomial.transform(x_test) polynomial=MultinomialNB() clm_nomial=polynomial.fit(train_matrix,y_train) result_nomial=clm_nomial.predict(test_matrix) #伯努利模型分类垃圾短信 train_matrix=vector_bernou.fit_transform(x_train) test_matrix=vector_bernou.transform(x_test) Bernoulli=BernoulliNB() clm_bernoulli=Bernoulli.fit(train_matrix,y_train) result_bernou=clm_bernoulli.predict(test_matrix) print('多项式模型的预测结果,类型，长度：') print(result_nomial,type(result_nomial),result_nomial.shape) print('多项式模型的前一百个预测结果：') print(result_nomial[0:100]) print('多项式模型模型R²评分：'+ str(clm_nomial.score(test_matrix,y_test))) print('\n----------------------------------\n') print('伯努利模型的预测结果,类型，长度：') print(result_bernou,type(result_bernou),result_bernou.shape) print('伯努利模型的前一百个预测结果：') print(result_bernou[0:100]) print('伯努利模型R²评分：'+ str(clm_bernoulli.score(test_matrix,y_test)))

时间: 2024-02-17 07:04:20 浏览: 50
这段代码是一个简单的垃圾短信分类器的实现。具体来说，它使用了朴素贝叶斯算法中的多项式模型和伯努利模型来分类短信为垃圾短信或非垃圾短信。以下是代码的详细解释： 1. 导入必要的库和模块： ```python from sklearn.naive_bayes import BernoulliNB, MultinomialNB from sklearn.feature_extraction.text import CountVectorizer from sklearn.model_selection import train_test_split import pandas as pd ``` 2. 读取数据集，并将标签值替换为0或1： ```python path = 'E:/Python_file/zuoye/SMSSpamCollection.txt' Cnames=['labels','messages'] data = pd.read_csv(path, sep='\t', header=None, names=Cnames) data = data.replace({'ham':0, 'spam':1}) ``` 3. 划分训练集和测试集： ```python X = data['messages'] y = data['labels'] x_train, x_test, y_train, y_test = train_test_split(X, y, train_size=0.8, random_state=123) ``` 4. 实现词袋模型和多项式模型： ```python vector_nomial = CountVectorizer() # 实现词袋模型 vector_bernou = CountVectorizer() # 多项式模型 ``` 5. 使用多项式模型分类垃圾短信： ```python train_matrix = vector_nomial.fit_transform(x_train) test_matrix = vector_nomial.transform(x_test) polynomial = MultinomialNB() clm_nomial = polynomial.fit(train_matrix, y_train) result_nomial = clm_nomial.predict(test_matrix) ``` 6. 使用伯努利模型分类垃圾短信： ```python train_matrix = vector_bernou.fit_transform(x_train) test_matrix = vector_bernou.transform(x_test) Bernoulli = BernoulliNB() clm_bernoulli = Bernoulli.fit(train_matrix, y_train) result_bernou = clm_bernoulli.predict(test_matrix) ``` 7. 输出结果： ```python print('多项式模型的预测结果,类型，长度：') print(result_nomial, type(result_nomial), result_nomial.shape) print('多项式模型的前一百个预测结果：') print(result_nomial[0:100]) print('多项式模型模型R²评分：'+ str(clm_nomial.score(test_matrix, y_test))) print('\n----------------------------------\n') print('伯努利模型的预测结果,类型，长度：') print(result_bernou, type(result_bernou), result_bernou.shape) print('伯努利模型的前一百个预测结果：') print(result_bernou[0:100]) print('伯努利模型R²评分：'+ str(clm_bernoulli.score(test_matrix, y_test))) ``` 其中，输出结果包括模型的预测结果、类型、长度、前一百个预测结果以及模型的R²评分。

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import pandas as pd from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.naive_bayes import GaussianNB from sklearn.model_selection import train_test_split from sklearn.feature_extraction.text import TfidfVectorizer # df1是经过预处理后的数据集，包含content_clean和category两列 X = df1['content_clean'] y = df1['category'] # 将数据集划分为训练集和测试集 train_X, test_X, train_y, test_y = train_test_split(X, y, test_size=0.2,) # 向量化文本 vectorizer = TfidfVectorizer() train_vectors = vectorizer.fit_transform(train_X) test_vectors = vectorizer.transform(test_X) # X_dense = X.toarray() classifier=GaussianNB().fit(train_vectors, train_labels)

from sklearn.model_selection import train_test_split # df1是经过预处理后的数据集，包含content_clean和category两列 X = df1['content_clean'] y = df1['category'] # 将数据集划分为训练集和测试集 ...

能否优化以下程序，使用test.csv和train.csv,程序如下:import pandas as pd from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.model_selection import train_test_split from sklearn.naive_bayes import MultinomialNB # 加载 CSV 文件 df = pd.read_csv('news.csv', encoding='utf-8', error_bad_lines=False) # 删除无效行 df.dropna(inplace=True) # 划分训练集和测试集 X_train, X_test, y_train, y_test = train_test_split(df['content'], df['category'], test_size=0.2) # 特征提取 vectorizer = TfidfVectorizer() X_train = vectorizer.fit_transform(X_train) X_test = vectorizer.transform(X_test) # 训练模型 model = MultinomialNB() model.fit(X_train, y_train) # 测试模型 score = model.score(X_test, y_test) print('Accuracy:', score)

from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.model_selection import train_test_split from sklearn.naive_bayes import MultinomialNB # 加载 CSV 文件 train_df = pd.read_csv('...

能否优化以下程序import pandas as pd from sklearn.model_selection import train_test_split from sklearn.feature_extraction.text import CountVectorizer from sklearn.naive_bayes import MultinomialNB # 读取数据集 df = pd.read_csv('news_dataset.csv', error_bad_lines=False) # 划分数据集 X_train, X_test, y_train, y_test = train_test_split(df['text'], df['label'], test_size=0.2) # 将文本转换为数字向量 vectorizer = CountVectorizer() X_train_vec = vectorizer.fit_transform(X_train) X_test_vec = vectorizer.transform(X_test) # 训练朴素贝叶斯分类器 classifier = MultinomialNB() classifier.fit(X_train_vec, y_train) # 预测测试集 y_pred = classifier.predict(X_test_vec) # 计算准确率 accuracy = (y_pred == y_test).sum() / y_test.shape[0] print(f'Accuracy: {accuracy}')

from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.naive_bayes import MultinomialNB # 读取数据集，指定数据类型 df = pd.read_csv('news_dataset.csv', error_bad_lines=False, dtype...

修改代码，使用其他方式跳过错误行，import pandas as pd from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.model_selection import train_test_split from sklearn.naive_bayes import MultinomialNB #加载 CSV 文件并忽略错误行 train_df = pd.read_csv('train.csv', encoding='utf-8', error_bad_lines=False) test_df = pd.read_csv('test.csv', encoding='utf-8', error_bad_lines=False) #删除无效行 train_df.dropna(inplace=True) test_df.dropna(inplace=True) #划分训练集和测试集 X_train = train_df['content'] y_train = train_df['category'] X_test = test_df['content'] y_test = test_df #特征提取 vectorizer = TfidfVectorizer() X_train = vectorizer.fit_transform(X_train) X_test = vectorizer.transform(X_test) #训练模型 model = MultinomialNB() model.fit(X_train, y_train) #测试模型 score = model.score(X_test, y_test) print('Accuracy:', score)

from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.model_selection import train_test_split from sklearn.naive_bayes import MultinomialNB #加载 CSV 文件并忽略错误行 try: ...

import pandas as pd from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.model_selection import train_test_split from sklearn.naive_bayes import MultinomialNB # 加载 CSV 文件 train_df = pd.read_csv('train.csv', encoding='utf-8', error_bad_lines=False) test_df = pd.read_csv('test.csv', encoding='utf-8', error_bad_lines=False) # 删除无效行 train_df.dropna(inplace=True) test_df.dropna(inplace=True) # 划分训练集和测试集 X_train = train_df['content'] y_train = train_df['category'] X_test = test_df['content'] y_test = test_df['category'] # 特征提取 vectorizer = TfidfVectorizer() X_train = vectorizer.fit_transform(X_train) X_test = vectorizer.transform(X_test) # 训练模型 model = MultinomialNB() model.fit(X_train, y_train) # 测试模型 score = model.score(X_test, y_test) print('Accuracy:', score)修改以上代码，使其使用error_bad_lines=False

from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.model_selection import train_test_split from sklearn.naive_bayes import MultinomialNB # 加载 CSV 文件并忽略错误行 train_df ...

修改下列代码，替换参数 error_bad_lines，代码为：import pandas as pd from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.model_selection import train_test_split from sklearn.naive_bayes import MultinomialNB # 加载 CSV 文件 train_df = pd.read_csv('train.csv', encoding='utf-8', error_bad_lines=False) test_df = pd.read_csv('test.csv', encoding='utf-8', error_bad_lines=False) # 删除无效行 train_df.dropna(inplace=True) test_df.dropna(inplace=True) # 划分训练集和测试集 X_train = train_df['content'] y_train = train_df['category'] X_test = test_df['content'] y_test = test_df['category'] # 特征提取 vectorizer = TfidfVectorizer() X_train = vectorizer.fit_transform(X_train) X_test = vectorizer.transform(X_test) # 训练模型 model = MultinomialNB() model.fit(X_train, y_train) # 测试模型 score = model.score(X_test, y_test) print('Accuracy:', score)

from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.model_selection import train_test_split from sklearn.naive_bayes import MultinomialNB # 加载 CSV 文件 train_df = pd.read_...

优化import pandas as pd from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.model_selection import train_test_split from sklearn.naive_bayes import MultinomialNB #加载 CSV 文件并忽略错误行 try: train_df = pd.read_csv('train.csv', encoding='utf-8') except: pass try: test_df = pd.read_csv('test.csv', encoding='utf-8') except: pass #删除无效行 train_df.dropna(inplace=True) test_df.dropna(inplace=True) #划分训练集和测试集 X_train = train_df['content'] y_train = train_df['category'] X_test = test_df['content'] y_test = test_df #特征提取 vectorizer = TfidfVectorizer() X_train = vectorizer.fit_transform(X_train) X_test = vectorizer.transform(X_test) #训练模型 model = MultinomialNB() model.fit(X_train, y_train) #测试模型 score = model.score(X_test, y_test) print('Accuracy:', score)

from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.model_selection import train_test_split from sklearn.naive_bayes import MultinomialNB # 加载 CSV 文件并忽略错误行 with ...

详细分析代码”import re from sklearn.feature_extraction.text import CountVectorizer from sklearn.model_selection import train_test_split from sklearn.naive_bayes import MultinomialNB class TextClassifier(): def __init__(self, classifier=MultinomialNB()): self.classifier = classifier self.vectorizer = CountVectorizer(analyzer='word' ,ngram_range=(1,4) ,max_features=20000) def features(self, X): return self.vectorizer.transform(X) def fit(self, X, y): self.vectorizer.fit(X) self.classifier.fit(self.features(X), y) def predict(self, x): return self.classifier.predict(self.features([x])) def score(self, X, y): return self.classifier.score(self.features(X), y)“并添加注释，每段代码的作用及蚕食代表什么

from sklearn.feature_extraction.text import CountVectorizer from sklearn.model_selection import train_test_split from sklearn.naive_bayes import MultinomialNB # 定义文本分类器类 class ...

修改代码，使用skiprows参数，跳过包含错误行的行：import pandas as pdfrom sklearn.feature_extraction.text import TfidfVectorizerfrom sklearn.model_selection import train_test_splitfrom sklearn.naive_bayes import MultinomialNB# 加载 CSV 文件train_df = pd.read_csv('train.csv', encoding='utf-8', error_bad_lines=False)test_df = pd.read_csv('test.csv', encoding='utf-8', error_bad_lines=False)# 删除无效行train_df.dropna(inplace=True)test_df.dropna(inplace=True)# 划分训练集和测试集X_train = train_df['content']y_train = train_df['category']X_test = test_df['content']y_test = test_df['category']# 特征提取vectorizer = TfidfVectorizer()X_train = vectorizer.fit_transform(X_train)X_test = vectorizer.transform(X_test)# 训练模型model = MultinomialNB()model.fit(X_train, y_train)# 测试模型score = model.score(X_test, y_test)print('Accuracy:', score)

from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.model_selection import train_test_split from sklearn.naive_bayes import MultinomialNB # 加载 CSV 文件，跳过错误行 train_df = ...

详细分析代码“from sklearn.cross_validation import StratifiedKFold from sklearn.naive_bayes import MultinomialNB from sklearn.metrics import accuracy_score,precision_score #from sklearn.model_selection import train_test_split x,y=zip(*sentences) from sklearn.feature_extraction.text import CountVectorizer vec = CountVectorizer( analyzer='word', # tokenise by character ngrams ngram_range=(1,4), # use ngrams of size 1 and 2 max_features=20000, # keep the most common 1000 ngrams ) vec.fit(x) def stratifiedkfold_cv(x,y,clf_class,shuffle=True,n_folds=5,**kwargs): stratifiedk_fold = StratifiedKFold(y, n_folds=n_folds, shuffle=shuffle) y_pred = y[:] for train_index, test_index in stratifiedk_fold: X_train, X_test = x[train_index], x[test_index] y_train = y[train_index] clf = clf_class(**kwargs) clf.fit(X_train,y_train) y_pred[test_index] = clf.predict(X_test) return y_pred NB = MultinomialNB print(precision_score(y ,stratifiedkfold_cv(vec.transform(x) ,np.array(y),NB) , average='macro'))”并添加注释，每段代码的作用，参数代表什么

from sklearn.feature_extraction.text import CountVectorizer vec = CountVectorizer( analyzer='word', # 按照单词进行分割 ngram_range=(1,4), # 使用1~4个单词的组合方式 max_features=20000, # 保留最...

帮我优化下面程序import pandas as pd from sklearn.feature_extraction.text import CountVectorizer from sklearn.naive_bayes import MultinomialNB # 读取训练数据集 train_df = pd.read_csv('train.csv') # 读取测试数据集 test_df = pd.read_csv('test.csv') # 将文本数据转换成向量形式 vectorizer = CountVectorizer() train_vectors = vectorizer.fit_transform(train_df['text']) test_vectors = vectorizer.transform(test_df['text']) # 使用朴素贝叶斯分类器进行分类 classifier = MultinomialNB() classifier.fit(train_vectors, train_df['label']) # 对测试数据集进行预测 predictions = classifier.predict(test_vectors) # 输出预测结果 for i, prediction in enumerate(predictions): print(f"Prediction for news {i+1}: {prediction}")，让它复杂点

from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.naive_bayes import MultinomialNB from sklearn.ensemble import VotingClassifier from sklearn.pipeline import Pipeline from ...

import pandas as pd import numpy as np from csv import reader from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.naive_bayes import MultinomialNB from sklearn.metrics import accuracy_score from sklearn.model_selection import train_test_split filename = 'D:/111/20news-18828.tar/20newsgroups.srv' with open(filename, 'rt', encoding='UTF-8') as file: A = file.readlines() data = np.array(A) df = pd.DataFrame(data, columns=['text']) # 分割数据集为训练集和测试集 X_train, X_test, y_train, y_test = train_test_split(df['text'], df['category'], random_state=42) # 对文本进行特征提取 tfidf = TfidfVectorizer(stop_words='english') X_train_tfidf = tfidf.fit_transform(X_train.astype(str)) X_test_tfidf = tfidf.transform(X_test.astype(str)) # 使用多项式朴素贝叶斯模型进行训练和预测 clf = MultinomialNB() clf.fit(X_train_tfidf, y_train) y_pred = clf.predict(X_test_tfidf.toarray()) # 输出模型的准确率 print('Accuracy:', accuracy_score(y_test, y_pred))是否有错误

from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.naive_bayes import MultinomialNB from sklearn.metrics import accuracy_score from sklearn.model_selection import train_test_...

import pandas as pdimport numpy as npfrom csv import readerfrom sklearn.feature_extraction.text import TfidfVectorizerfrom sklearn.naive_bayes import MultinomialNBfrom sklearn.metrics import accuracy_scorefrom sklearn.model_selection import train_test_splitfilename = input("请输入文件名：")with open(filename, 'rt', encoding='UTF-8') as file: A = file.readlines()data = np.array(A)df = pd.DataFrame(data, columns=['text'])# 分割数据集为训练集和测试集X_train, X_test, y_train, y_test = train_test_split(df['text'], df['category'], random_state=42)# 对文本进行特征提取tfidf = TfidfVectorizer(stop_words='english')X_train_tfidf = tfidf.fit_transform(X_train.astype(str))X_test_tfidf = tfidf.transform(X_test.astype(str))# 使用多项式朴素贝叶斯模型进行训练和预测clf = MultinomialNB()clf.fit(X_train_tfidf, y_train)y_pred = clf.predict(X_test_tfidf.toarray())# 输出模型的准确率print('Accuracy:', accuracy_score(y_test, y_pred))如何修改能导入我计算机上的文件

from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.naive_bayes import MultinomialNB from sklearn.metrics import accuracy_score from sklearn.model_selection import train_test_...

给出这段用于电影评论分类代码的详细思路“from sklearn.cross_validation import StratifiedKFold from sklearn.naive_bayes import MultinomialNB from sklearn.metrics import accuracy_score,precision_score #from sklearn.model_selection import train_test_split x,y=zip(*sentences) from sklearn.feature_extraction.text import CountVectorizer vec = CountVectorizer( analyzer='word', # tokenise by character ngrams ngram_range=(1,4), # use ngrams of size 1 and 2 max_features=20000, # keep the most common 1000 ngrams ) vec.fit(x) def stratifiedkfold_cv(x,y,clf_class,shuffle=True,n_folds=5,**kwargs): stratifiedk_fold = StratifiedKFold(y, n_folds=n_folds, shuffle=shuffle) y_pred = y[:] for train_index, test_index in stratifiedk_fold: X_train, X_test = x[train_index], x[test_index] y_train = y[train_index] clf = clf_class(**kwargs) clf.fit(X_train,y_train) y_pred[test_index] = clf.predict(X_test) return y_pred NB = MultinomialNB print(precision_score(y ,stratifiedkfold_cv(vec.transform(x) ,np.array(y),NB) , average='macro'))”分析每一部分代码的作用，给出整体思路框架

这段代码是用于电影评论分类的，主要使用了sklearn库中的StratifiedKFold、MultinomialNB和CountVectorizer等模块。具体思路如下： 1. 从sklearn中导入需要的模块，包括StratifiedKFold、MultinomialNB和...

Visual Studio Code能否import pandas as pdimport numpy as npfrom sklearn.feature_extraction.text import TfidfVectorizerfrom sklearn.naive_bayes import MultinomialNBfrom sklearn.metrics import accuracy_scorefrom sklearn.model_selection import train_test_splitfilename = 'D:/111/20news-18828.tar/20newsgroups.srv'with open(filename, 'r', encoding='UTF-8') as file: A = file.readlines()data = []for line in A: category, text = line.split('\t') data.append((category, text))df = pd.DataFrame(data, columns=['category', 'text'])# 分割数据集为训练集和测试集X_train, X_test, y_train, y_test = train_test_split(df['text'], df['category'], random_state=42)# 对文本进行特征提取tfidf = TfidfVectorizer(stop_words='english')X_train_tfidf = tfidf.fit_transform(X_train.astype(str))X_test_tfidf = tfidf.transform(X_test.astype(str))# 使用多项式朴素贝叶斯模型进行训练和预测clf = MultinomialNB()clf.fit(X_train_tfidf, y_train)y_pred = clf.predict(X_test_tfidf)# 输出模型的准确率print('Accuracy:', accuracy_score(y_test, y_pred))显示结果

Visual Studio Code可以import pandas as pd、import numpy as np、from sklearn.feature_extraction.text import TfidfVectorizer、from sklearn.naive_bayes import MultinomialNB、from sklearn.metrics import ...

from sklearn.datasets import fetch_20news18828 from sklearn.model_selection import train_test_split from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.naive_bayes import MultinomialNB def bayesian_demo(): ''' 朴素贝叶斯-文本分类 :return: ''' # 1. 获取数据 news = fetch_20news18828(subset='all') # 2. 划分数据集 x_train, x_test, y_train, y_test = train_test_split(news.data, news.target, test_size=0.2) # 3. 特征工程 transfer = TfidfVectorizer() x_train = transfer.fit_transform(x_train) x_test = transfer.transform(x_test) # 4. 朴素贝叶斯算法预估器流程 estimator = MultinomialNB() estimator.fit(x_train, y_train) # 5. 模型评估 # 5.1 直接对比真实值、预测值 y_predict = estimator.predict(x_test) print('y_predic:\n', y_predict) print('直接对比真实值与预测值：\n', y_test == y_predict) # 5.2 计算准确率 score = estimator.score(x_test,y_test) print('准确率为：\n', score) if __name__ == '__main__': bayesian_demo()

2. 使用train_test_split函数将数据集划分为训练集和测试集。 3. 使用TfidfVectorizer类将文本转换为TF-IDF特征向量。 4. 创建MultinomialNB类的实例，用fit函数对训练集进行拟合。 5. 对测试集进行预测，使用score...

import pandas as pd df = pd.read_csv(filename, header=None, names=['category', 'text']) from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.naive_bayes import MultinomialNB from sklearn.metrics import accuracy_score # 读取新闻文本数据 from csv import readerimport numpy as np filename = input("请输入文件名：") with open(filename,'rt',encoding = 'UTF-8') as file: readers = reader(raw_data,delimiter=',') A = list(file) data = np.array(A)print(data) df = pd.read_csv('20news-18828') # 分割数据集为训练集和测试集 X_train, X_test, y_train, y_test = train_test_split(df['text'], df['category'], random_state=42) # 对文本进行特征提取 tfidf = TfidfVectorizer(stop_words='english') X_train = X_train.astype(str) X_test = X_test.astype(str) # 使用多项式朴素贝叶斯模型进行训练和预测 clf = MultinomialNB() clf.fit(X_train_tfidf, y_train) y_pred = clf.predict(X_test_tfidf.toarray()) # 输出模型的准确率 print('Accuracy:', accuracy_score(y_test, y_pred))是否有问题

from sklearn.feature_extraction.text import TfidfVectorizer from sklearn.naive_bayes import MultinomialNB from sklearn.metrics import accuracy_score from sklearn.model_selection import train_test_...

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