Python实现的IDA算法及应用实例

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资源摘要信息:"在本节中,我们将深入探讨标题中提到的IDA算法以及Python实现的相关知识点。标题中包含了一系列的关键词:'lda.zip'、'ida python'、'ida算法'、'python_lda'、'pda_lda算法python',这些关键词揭示了文档中可能包含的内容。描述部分简单明了地指出文档将讲述如何使用Python来实现IDA算法,并强调了该实现的实用性。标签部分列出了与文档相关的关键词,帮助我们更精确地定位到文档所涉及的主题。最后,文件列表中仅包含一个文件名'lda.py',很可能是实现IDA算法的Python脚本文件。 1. IDA算法:Iterated Dichotomiser 3(IDA算法),是一种在决策树学习中使用的算法,它是C4.5算法的一个改进版本。ID3算法使用信息增益作为选择属性的标准,而C4.5则使用信息增益比。IDA算法的基本思想是在决策树构建的每一步中,选择最优的分裂属性,使得在该属性的条件下,数据集的熵最小。该算法适用于处理含有缺失值的数据集,并且可以有效防止过拟合。 2. Python实现:Python是一种广泛使用的高级编程语言,以其易读性和简洁的语法而著称。Python具有强大的库生态系统,可以用来实现各种复杂的算法,包括数据挖掘、机器学习等。在本资源中,我们将会了解到如何用Python编程语言来编写实现IDA算法的代码,重点是理解算法背后的逻辑和Python代码的结构。 3. Python中的LDA:在描述中提到了Python和LDA,可能指的是线性判别分析(Linear Discriminant Analysis),这是一种在机器学习和模式识别中常用的降维技术。LDA旨在找到一个特征空间,使得样本在这个空间中按类别尽可能分开,同时保持类别内部的紧凑性。线性判别分析常用于多分类问题,并且在处理文本数据或图像识别中十分常见。 4. PDA与LDA算法:PDA可能指的是概率判别分析(Probabilistic Discriminant Analysis),它是线性判别分析的一种概率扩展形式。PDA不仅考虑了类别的均值,还考虑了类别的协方差结构,通过概率模型对数据进行建模,使得算法更加健壮,能更好地处理具有复杂分布的数据集。 总结以上内容,本资源文件将介绍如何使用Python编程语言来实现IDA算法,并且可能会涉及到LDA和PDA等其他相关算法的讨论。文件的核心是'lda.py',这表明学习者可以期待一个可以直接运行的Python脚本实例,以及可能的使用说明或代码注释来帮助理解算法的实现细节。掌握IDA算法将有助于学习者在决策树学习、数据分析以及机器学习领域更深层次地应用Python进行实践。"

import pandas as pd from openpyxl import Workbook # 获取主题下词语的概率分布 def get_topic_word_distribution(lda, tf_feature_names): arr = lda.transform(tf_vectorizer.transform([' '.join(tf_feature_names)])) return arr[0] # 打印主题下词语的概率分布 def print_topic_word_distribution(lda, tf_feature_names, n_top_words): dist = get_topic_word_distribution(lda, tf_feature_names) for i in range(lda.n_components): print("Topic {}: {}".format(i, ', '.join("{:.4f}".format(x) for x in dist[i]))) # 输出每个主题下词语的概率分布至Excel表格 def output_topic_word_distribution_to_excel(lda, tf_feature_names, n_top_words,filename): # 创建Excel工作簿和工作表 wb = Workbook() ws = wb.active ws.title = "Topic Word Distribution" # 添加表头 ws.cell(row=1, column=1).value = "Topic" for j in range(n_top_words): ws.cell(row=1, column=j+2).value = tf_feature_names[j] # 添加每个主题下词语的概率分布 dist = get_topic_word_distribution(lda, tf_feature_names) for i in range(lda.n_components): ws.cell(row=i+2, column=1).value = i for j in range(n_top_words): ws.cell(row=i+2, column=j+2).value = dist[i][j] # 保存Excel文件 wb.save(filename) n_top_words = 30 tf_feature_names = tf_vectorizer.get_feature_names() topic_word = print_topic_word_distribution(lda, tf_feature_names, n_top_words)报错Traceback (most recent call last): File "D:\python\lda3\data_1.py", line 157, in <module> topic_word = print_topic_word_distribution(lda, tf_feature_names, n_top_words) File "D:\python\lda3\data_1.py", line 130, in print_topic_word_distribution print("Topic {}: {}".format(i, ', '.join("{:.4f}".format(x) for x in dist[i]))) TypeError: 'numpy.float64' object is not iterable

2023-05-26 上传

把这段代码的PCA换成LDA:LR_grid = LogisticRegression(max_iter=1000, random_state=42) LR_grid_search = GridSearchCV(LR_grid, param_grid=param_grid, cv=cvx ,scoring=scoring,n_jobs=10,verbose=0) LR_grid_search.fit(pca_X_train, train_y) estimators = [ ('lr', LR_grid_search.best_estimator_), ('svc', svc_grid_search.best_estimator_), ] clf = StackingClassifier(estimators=estimators, final_estimator=LinearSVC(C=5, random_state=42),n_jobs=10,verbose=1) clf.fit(pca_X_train, train_y) estimators = [ ('lr', LR_grid_search.best_estimator_), ('svc', svc_grid_search.best_estimator_), ] param_grid = {'final_estimator':[LogisticRegression(C=0.00001),LogisticRegression(C=0.0001), LogisticRegression(C=0.001),LogisticRegression(C=0.01), LogisticRegression(C=0.1),LogisticRegression(C=1), LogisticRegression(C=10),LogisticRegression(C=100), LogisticRegression(C=1000)]} Stacking_grid =StackingClassifier(estimators=estimators,) Stacking_grid_search = GridSearchCV(Stacking_grid, param_grid=param_grid, cv=cvx, scoring=scoring,n_jobs=10,verbose=0) Stacking_grid_search.fit(pca_X_train, train_y) Stacking_grid_search.best_estimator_ train_pre_y = cross_val_predict(Stacking_grid_search.best_estimator_, pca_X_train,train_y, cv=cvx) train_res1=get_measures_gridloo(train_y,train_pre_y) test_pre_y = Stacking_grid_search.predict(pca_X_test) test_res1=get_measures_gridloo(test_y,test_pre_y) best_pca_train_aucs.append(train_res1.loc[:,"AUC"]) best_pca_test_aucs.append(test_res1.loc[:,"AUC"]) best_pca_train_scores.append(train_res1) best_pca_test_scores.append(test_res1) train_aucs.append(np.max(best_pca_train_aucs)) test_aucs.append(best_pca_test_aucs[np.argmax(best_pca_train_aucs)].item()) train_scores.append(best_pca_train_scores[np.argmax(best_pca_train_aucs)]) test_scores.append(best_pca_test_scores[np.argmax(best_pca_train_aucs)]) pca_comp.append(n_components[np.argmax(best_pca_train_aucs)]) print("n_components:") print(n_components[np.argmax(best_pca_train_aucs)])

2023-07-22 上传

n_topics = 10 lda = LatentDirichletAllocation(n_components=n_topics, max_iter=50, learning_method='batch', learning_offset=50, #doc_topic_prior=0.1, #topic_word_prior=0.01, random_state=0) lda.fit(tf) ###########每个主题对应词语 import pandas as pd from openpyxl import Workbook # 获取主题下词语的概率分布 def get_topic_word_distribution(lda, tf_feature_names): arr = lda.transform(tf_vectorizer.transform([' '.join(tf_feature_names)])) return arr[0] # 打印主题下词语的概率分布 def print_topic_word_distribution(lda, tf_feature_names, n_top_words): dist = get_topic_word_distribution(lda, tf_feature_names) for i in range(lda.n_topics): print("Topic {}: {}".format(i, ', '.join("{:.4f}".format(x) for x in dist[i]))) # 输出每个主题下词语的概率分布至Excel表格 def output_topic_word_distribution_to_excel(lda, tf_feature_names, n_top_words, filename): # 创建Excel工作簿和工作表 wb = Workbook() ws = wb.active ws.title = "Topic Word Distribution" # 添加表头 ws.cell(row=1, column=1).value = "Topic" for j in range(n_top_words): ws.cell(row=1, column=j+2).value = tf_feature_names[j] # 添加每个主题下词语的概率分布 dist = get_topic_word_distribution(lda, tf_feature_names) for i in range(lda.n_topics): ws.cell(row=i+2, column=1).value = i for j in range(n_top_words): ws.cell(row=i+2, column=j+2).value = dist[i][j] # 保存Excel文件 wb.save(filename) n_top_words = 30 tf_feature_names = tf_vectorizer.get_feature_names() topic_word = print_topic_word_distribution(lda, tf_feature_names, n_top_words) #print_topic_word_distribution(lda, tf_feature_names, n_top_words) output_topic_word_distribution_to_excel(lda, tf_feature_names, n_top_words, "topic_word_distribution.xlsx")报错Traceback (most recent call last): File "D:\python\lda3\data_1.py", line 157, in <module> topic_word = print_topic_word_distribution(lda, tf_feature_names, n_top_words) File "D:\python\lda3\data_1.py", line 129, in print_topic_word_distribution for i in range(lda.n_topics): AttributeError: 'LatentDirichletAllocation' object has no attribute 'n_topics'

2023-05-25 上传