import pandas as pd import os from sklearn.model_selection import train_test_split from sklearn.ensemble import RandomForestClassifier from sklearn.metrics import accuracy_score # 计算准确性 import numpy as np from sklearn.tree import plot_tree import matplotlib.pyplot as plt # 画图 from sklearn.metrics import confusion_matrix # 绘制混淆矩阵时使用 from sklearn.metrics import roc_curve, auc # 绘制ROC曲线时使用 from sklearn.preprocessing import label_binarize # 使用sklearn中的LabelBinarizer可以将多分类标签转化为二分类标签 from sklearn.preprocessing import LabelEncoder from sklearn.preprocessing import LabelBinarizer
时间: 2023-10-26 13:04:45 浏览: 179
您的代码看起来像是在使用Python中的一些流行的机器学习库,如Pandas、Scikit-learn和Numpy。通过这些库,您可以进行数据处理、训练和评估机器学习模型。
具体来说,您的代码中使用了以下功能:
- 导入了pandas、os、sklearn等库;
- 使用sklearn中的train_test_split函数将数据集分为训练集和测试集;
- 使用RandomForestClassifier(随机森林分类器)进行分类任务;
- 使用accuracy_score函数计算模型的准确度;
- 导入numpy库;
- 使用plot_tree函数绘制决策树;
- 使用confusion_matrix函数绘制混淆矩阵;
- 使用roc_curve和auc函数绘制ROC曲线;
- 使用LabelEncoder和LabelBinarizer函数将标签进行编码。
总的来说,这些功能可以帮助您构建和评估机器学习模型。
相关问题
import pandas as pd from sklearn.datasets import load_wine from sklearn.model_selection import train_test_split from sklearn.linear_model import LogisticRegression from sklearn.feature_selection import SelectKBest, f_classif from sklearn.decomposition import PCA from sklearn.metrics import accuracy_score, classification_report from sklearn.tree import DecisionTreeClassifier from sklearn.metrics import accuracy_score from sklearn.ensemble import RandomForestClassifier from sklearn.neighbors import KNeighborsClassifier from sklearn.naive_bayes import GaussianNB from sklearn.linear_model import LogisticRegression from sklearn.svm import SVC data = load_wine() # 导入数据集 X = pd.DataFrame(data.data, columns=data.feature_names) y = pd.Series(data.target) # 划分训练集和测试集 X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.2, random_state=0) # 构建分类模型 model = LogisticRegression() model.fit(X_train, y_train) # 预测测试集结果 y_pred = model.predict(X_test) #评估模型性能 accuracy = accuracy_score(y_test, y_pred) report = classification_report(y_test, y_pred) print('准确率:', accuracy) # 特征选择 selector = SelectKBest(f_classif, k=6) X_new = selector.fit_transform(X, y) print('所选特征:', selector.get_support()) # 模型降维 pca = PCA(n_components=2) X_new = pca.fit_transform(X_new) # 划分训练集和测试集 X_train, X_test, y_train, y_test = train_test_split(X_new, y, test_size=0.2, random_state=0) def Sf(model,X_train, X_test, y_train, y_test,modelname): mode = model() mode.fit(X_train, y_train) y_pred = mode.predict(X_test) accuracy = accuracy_score(y_test, y_pred) print(modelname, accuracy) importance = mode.feature_importances_ print(importance) def Sf1(model,X_train, X_test, y_train, y_test,modelname): mode = model() mode.fit(X_train, y_train) y_pred = mode.predict(X_test) accuracy = accuracy_score(y_test, y_pred) print(modelname, accuracy) modelname='支持向量机' Sf1(SVC,X_train, X_test, y_train, y_test,modelname) modelname='逻辑回归' Sf1(LogisticRegression,X_train, X_test, y_train, y_test,modelname) modelname='高斯朴素贝叶斯算法训练分类器' Sf1(GaussianNB,X_train, X_test, y_train, y_test,modelname) modelname='K近邻分类' Sf1(KNeighborsClassifier,X_train, X_test, y_train, y_test,modelname) modelname='决策树分类' Sf(DecisionTreeClassifier,X_train, X_test, y_train, y_test,modelname) modelname='随机森林分类' Sf(RandomForestClassifier,X_train, X_test, y_train, y_test,modelname)加一个画图展示
抱歉,由于我是一个纯文本AI,无法进行画图展示。但是,你可以使用Python中的matplotlib库进行数据可视化。例如,你可以使用以下代码绘制特征重要性条形图:
import matplotlib.pyplot as plt
importance = mode.feature_importances_
features = list(X.columns)
plt.barh(features, importance)
plt.title('Feature Importance')
plt.xlabel('Importance')
plt.show()
这段代码可以在Sf函数中的print(importance)下方添加,并在运行时展示特征重要性条形图。
import numpy as np import pandas as pd from sklearn.model_selection import train_test_split, GridSearchCV from sklearn.metrics import accuracy_score, precision_score, recall_score, f1_score from sklearn.metrics import confusion_matrix import matplotlib.pyplot as plt from termcolor import colored as cl import itertools from sklearn.preprocessing import StandardScaler from sklearn.tree import DecisionTreeClassifier from sklearn.neighbors import KNeighborsClassifier from sklearn.linear_model import LogisticRegression from sklearn.svm import SVC from sklearn.ensemble import RandomForestClassifier from xgboost import XGBClassifier from sklearn.neural_network import MLPClassifier from sklearn.ensemble import VotingClassifier # 定义模型评估函数 def evaluate_model(y_true, y_pred): accuracy = accuracy_score(y_true, y_pred) precision = precision_score(y_true, y_pred, pos_label='Good') recall = recall_score(y_true, y_pred, pos_label='Good') f1 = f1_score(y_true, y_pred, pos_label='Good') print("准确率:", accuracy) print("精确率:", precision) print("召回率:", recall) print("F1 分数:", f1) # 读取数据集 data = pd.read_csv('F:\数据\大学\专业课\模式识别\大作业\数据集1\data clean Terklasifikasi baru 22 juli 2015 all.csv', skiprows=16, header=None) # 检查数据集 print(data.head()) # 划分特征向量和标签 X = data.iloc[:, :-1] y = data.iloc[:, -1] # 划分训练集和测试集 X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.2, random_state=42) # 6. XGBoost xgb = XGBClassifier(max_depth=4) y_test = np.array(y_test, dtype=int) xgb.fit(X_train, y_train) xgb_pred = xgb.predict(X_test) print("\nXGBoost评估结果:") evaluate_model(y_test, xgb_pred)
这段代码实现了一个使用XGBoost算法进行分类的机器学习模型,并对该模型进行评估。具体步骤如下:
1. 导入需要的库:numpy、pandas、sklearn等。
2. 定义模型评估函数:evaluate_model(y_true, y_pred),该函数用于计算模型预测结果的准确率、精确率、召回率和F1分数。
3. 读取数据集:使用pandas库的read_csv()函数读取数据集。
4. 划分特征向量和标签:将数据集划分为特征向量X和标签y。
5. 划分训练集和测试集:使用sklearn库的train_test_split()函数将数据集划分为训练集和测试集。
6. 使用XGBoost算法进行分类:使用XGBClassifier类构建XGBoost分类器,并使用fit()函数将训练集拟合到该分类器中。然后,使用predict()函数对测试集进行预测,并将预测结果存储在xgb_pred中。
7. 对模型进行评估:使用evaluate_model()函数对模型进行评估,并输出准确率、精确率、召回率和F1分数等评估结果。
需要注意的是:该代码中的数据集路径可能需要修改为本地数据集路径。
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