import numpy as np from sklearn.model_selection import train_test_split, cross_val_score from sklearn.ensemble import RandomForestClassifier from sklearn.preprocessing import PolynomialFeatures, StandardScaler id = "202210423104" name = "张钦诚" def load_data(filepath): data = [] with open(filepath, 'r') as file: for line in file: line_data = line.strip().split() if line_data: try: data.append([float(x) if x != '?' else np.nan for x in line_data]) except ValueError as e: print(f"Error processing line: {line}. Error: {e}") data = np.array(data) data = np.nan_to_num(data, nan=np.nanmean(data, axis=0)) return data def preprocess_data(X): # 标准化特征 scaler = StandardScaler() X_standardized = scaler.fit_transform(X) # 增加多项式特征 poly = PolynomialFeatures(degree=2, include_bias=False) X_poly = poly.fit_transform(X_standardized) return X_poly def train_random_forest(X, y): model = RandomForestClassifier(n_estimators=113, max_depth=10, random_state=42) model.fit(X, y) return model def predict(model, X): return model.predict(X) if __name__ == "__main__": data = load_data("./data/horse-colic.data") X = data[:, :-1] y = data[:, -1] # 数据集划分 X_train, X_test, y_train, y_test = train_test_split(X, y, test_size=0.2, random_state=42) # 数据预处理 X_train_processed = preprocess_data(X_train) X_test_processed = preprocess_data(X_test) # 训练模型 model = train_random_forest(X_train_processed, y_train) # 交叉验证 cv_scores = cross_val_score(model, X_train_processed, y_train, cv=5) print(f"交叉验证准确率: {np.mean(cv_scores) * 100:.2f}%") # 预测 y_pred = predict(model, X_test_processed) # 计算正确率 accuracy = np.mean(y_pred == y_test) print(f"测试出的正确率: {accuracy * 100:.2f}%")