每个文本文件包含相对应类的数据(0:喜悦1:愤怒2:厌恶3:低落对应不同类别的感情)
- 文本读取
- 用均值的方差,在高斯分布里面计算某个词的概率。
- 对文本特征进行提取,提取词频。
- 通过词频在各种词频目录里面进行匹配。
- 对模型的准确率的预测。
main.py
1 # -*- coding: utf-8 -*- 2 import os 3 import pandas as pd 4 import nltk 5 from tools import proc_text, split_train_test, get_word_list_from_data, \ 6 extract_feat_from_data, cal_acc 7 from nltk.text import TextCollection 8 from sklearn.naive_bayes import GaussianNB 9 10 dataset_path = './dataset' 11 text_filenames = ['0_simplifyweibo.txt', '1_simplifyweibo.txt', 12 '2_simplifyweibo.txt', '3_simplifyweibo.txt'] 13 14 # 原始数据的csv文件 15 output_text_filename = 'raw_weibo_text.csv' 16 17 # 清洗好的文本数据文件 18 output_cln_text_filename = 'clean_weibo_text.csv' 19 20 # 处理和清洗文本数据的时间较长,通过设置is_first_run进行配置 21 # 如果是第一次运行需要对原始文本数据进行处理和清洗,需要设为True 22 # 如果之前已经处理了文本数据,并已经保存了清洗好的文本数据,设为False即可 23 is_first_run = True 24 25 26 def read_and_save_to_csv(): 27 """ 28 读取原始文本数据,将标签和文本数据保存成csv 29 """ 30 31 text_w_label_df_lst = [] 32 for text_filename in text_filenames: 33 text_file = os.path.join(dataset_path, text_filename) 34 35 # 获取标签,即0, 1, 2, 3 36 label = int(text_filename[0]) 37 38 # 读取文本文件 39 with open(text_file, 'r', encoding='utf-8') as f: 40 lines = f.read().splitlines() 41 42 labels = [label] * len(lines) 43 44 text_series = pd.Series(lines) 45 label_series = pd.Series(labels) 46 47 # 构造dataframe 48 text_w_label_df = pd.concat([label_series, text_series], axis=1) 49 text_w_label_df_lst.append(text_w_label_df) 50 51 result_df = pd.concat(text_w_label_df_lst, axis=0) 52 53 # 保存成csv文件 54 result_df.columns = ['label', 'text'] 55 result_df.to_csv(os.path.join(dataset_path, output_text_filename), 56 index=None, encoding='utf-8') 57 58 59 def run_main(): 60 """ 61 主函数 62 """ 63 # 1. 数据读取,处理,清洗,准备 64 if is_first_run: 65 print('处理清洗文本数据中...', end=' ') 66 # 如果是第一次运行需要对原始文本数据进行处理和清洗 67 68 # 读取原始文本数据,将标签和文本数据保存成csv 69 read_and_save_to_csv() 70 71 # 读取处理好的csv文件,构造数据集 72 text_df = pd.read_csv(os.path.join(dataset_path, output_text_filename), 73 encoding='utf-8') 74 75 # 处理文本数据 76 text_df['text'] = text_df['text'].apply(proc_text) 77 78 # 过滤空字符串 79 text_df = text_df[text_df['text'] != ''] 80 81 # 保存处理好的文本数据 82 text_df.to_csv(os.path.join(dataset_path, output_cln_text_filename), 83 index=None, encoding='utf-8') 84 print('完成,并保存结果。') 85 86 # 2. 分割训练集、测试集 87 print('加载处理好的文本数据') 88 clean_text_df = pd.read_csv(os.path.join(dataset_path, output_cln_text_filename), 89 encoding='utf-8') 90 # 分割训练集和测试集 91 train_text_df, test_text_df = split_train_test(clean_text_df) 92 # 查看训练集测试集基本信息 93 print('训练集中各类的数据个数:', train_text_df.groupby('label').size()) 94 print('测试集中各类的数据个数:', test_text_df.groupby('label').size()) 95 96 # 3. 特征提取 97 # 计算词频 98 n_common_words = 200 99 100 # 将训练集中的单词拿出来统计词频101 print('统计词频...')102 all_words_in_train = get_word_list_from_data(train_text_df)103 fdisk = nltk.FreqDist(all_words_in_train)104 common_words_freqs = fdisk.most_common(n_common_words)105 print('出现最多的{}个词是:'.format(n_common_words))106 for word, count in common_words_freqs:107 print('{}: {}次'.format(word, count))108 print()109 110 # 在训练集上提取特征111 text_collection = TextCollection(train_text_df['text'].values.tolist())112 print('训练样本提取特征...', end=' ')113 train_X, train_y = extract_feat_from_data(train_text_df, text_collection, common_words_freqs)114 print('完成')115 print()116 117 print('测试样本提取特征...', end=' ')118 test_X, test_y = extract_feat_from_data(test_text_df, text_collection, common_words_freqs)119 print('完成')120 121 # 4. 训练模型Naive Bayes122 print('训练模型...', end=' ')123 gnb = GaussianNB()124 gnb.fit(train_X, train_y)125 print('完成')126 print()127 128 # 5. 预测129 print('测试模型...', end=' ')130 test_pred = gnb.predict(test_X)131 print('完成')132 133 # 输出准确率134 print('准确率:', cal_acc(test_y, test_pred))135 136 if __name__ == '__main__':137 run_main()
tools.py
1 # -*- coding: utf-8 -*- 2 import re 3 import jieba.posseg as pseg 4 import pandas as pd 5 import math 6 import numpy as np 7 8 # 加载常用停用词 9 stopwords1 = [line.rstrip() for line in open('./中文停用词库.txt', 'r', encoding='utf-8')] 10 # stopwords2 = [line.rstrip() for line in open('./哈工大停用词表.txt', 'r', encoding='utf-8')] 11 # stopwords3 = [line.rstrip() for line in open('./四川大学机器智能实验室停用词库.txt', 'r', encoding='utf-8')] 12 # stopwords = stopwords1 + stopwords2 + stopwords3 13 stopwords = stopwords1 14 15 16 def proc_text(raw_line): 17 """ 18 处理每行的文本数据 19 返回分词结果 20 """ 21 # 1. 使用正则表达式去除非中文字符 22 filter_pattern = re.compile('[^\u4E00-\u9FD5]+') 23 chinese_only = filter_pattern.sub('', raw_line) 24 25 # 2. 结巴分词+词性标注 26 words_lst = pseg.cut(chinese_only) 27 28 # 3. 去除停用词 29 meaninful_words = [] 30 for word, flag in words_lst: 31 # if (word not in stopwords) and (flag == 'v'): 32 # 也可根据词性去除非动词等 33 if word not in stopwords: 34 meaninful_words.append(word) 35 36 return ' '.join(meaninful_words) 37 38 39 def split_train_test(text_df, size=0.8): 40 """ 41 分割训练集和测试集 42 """ 43 # 为保证每个类中的数据能在训练集中和测试集中的比例相同,所以需要依次对每个类进行处理 44 train_text_df = pd.DataFrame() 45 test_text_df = pd.DataFrame() 46 47 labels = [0, 1, 2, 3] 48 for label in labels: 49 # 找出label的记录 50 text_df_w_label = text_df[text_df['label'] == label] 51 # 重新设置索引,保证每个类的记录是从0开始索引,方便之后的拆分 52 text_df_w_label = text_df_w_label.reset_index() 53 54 # 默认按80%训练集,20%测试集分割 55 # 这里为了简化操作,取前80%放到训练集中,后20%放到测试集中 56 # 当然也可以随机拆分80%,20%(尝试实现下DataFrame中的随机拆分) 57 58 # 该类数据的行数 59 n_lines = text_df_w_label.shape[0] 60 split_line_no = math.floor(n_lines * size) 61 text_df_w_label_train = text_df_w_label.iloc[:split_line_no, :] 62 text_df_w_label_test = text_df_w_label.iloc[split_line_no:, :] 63 64 # 放入整体训练集,测试集中 65 train_text_df = train_text_df.append(text_df_w_label_train) 66 test_text_df = test_text_df.append(text_df_w_label_test) 67 68 train_text_df = train_text_df.reset_index() 69 test_text_df = test_text_df.reset_index() 70 return train_text_df, test_text_df 71 72 73 def get_word_list_from_data(text_df): 74 """ 75 将数据集中的单词放入到一个列表中 76 """ 77 word_list = [] 78 for _, r_data in text_df.iterrows(): 79 word_list += r_data['text'].split(' ') 80 return word_list 81 82 83 def extract_feat_from_data(text_df, text_collection, common_words_freqs): 84 """ 85 特征提取 86 """ 87 # 这里只选择TF-IDF特征作为例子 88 # 可考虑使用词频或其他文本特征作为额外的特征 89 90 n_sample = text_df.shape[0] 91 n_feat = len(common_words_freqs) 92 common_words = [word for word, _ in common_words_freqs] 93 94 # 初始化 95 X = np.zeros([n_sample, n_feat]) 96 y = np.zeros(n_sample) 97 98 print('提取特征...') 99 for i, r_data in text_df.iterrows():100 if (i + 1) % 5000 == 0:101 print('已完成{}个样本的特征提取'.format(i + 1))102 103 text = r_data['text']104 105 feat_vec = []106 for word in common_words:107 if word in text:108 # 如果在高频词中,计算TF-IDF值109 tf_idf_val = text_collection.tf_idf(word, text)110 else:111 tf_idf_val = 0112 113 feat_vec.append(tf_idf_val)114 115 # 赋值116 X[i, :] = np.array(feat_vec)117 y[i] = int(r_data['label'])118 119 return X, y120 121 122 def cal_acc(true_labels, pred_labels):123 """124 计算准确率125 """126 n_total = len(true_labels)127 correct_list = [true_labels[i] == pred_labels[i] for i in range(n_total)]128 129 acc = sum(correct_list) / n_total130 return acc