From 89f3ea43515977e0c7cdebcf3fd4875c68f7abc0 Mon Sep 17 00:00:00 2001 From: zhangchenghong <1598349064@qq.com> Date: Thu, 7 Nov 2024 16:42:29 +0800 Subject: [PATCH] =?UTF-8?q?=E6=9B=B4=E6=96=B0=20function.py?= MIME-Version: 1.0 Content-Type: text/plain; charset=UTF-8 Content-Transfer-Encoding: 8bit --- function.py | 150 ++++++++++++++++++++++------------------------------ 1 file changed, 63 insertions(+), 87 deletions(-) diff --git a/function.py b/function.py index 1982a05..c8f2c5f 100644 --- a/function.py +++ b/function.py @@ -27,110 +27,86 @@ name = "章程鸿" # 这里写自己的代码实现 import numpy as np -from sklearn.preprocessing import MinMaxScaler -from sklearn.model_selection import train_test_split def sigmoid(z): - return 1.0 / (1 + np.exp(-z)) + return 1 / (1 + np.exp(-z)) -def compute_gradient(X_batch, y_batch, weights, lambda_reg): - z = np.dot(X_batch, weights) - h = sigmoid(z) - gradient = np.dot(X_batch.T, (h - y_batch)) / len(y_batch) - gradient += (lambda_reg / len(y_batch)) * weights # L2正则化 - return gradient +def train_logreg(X, y, learning_rate=0.01, iterations=1000): + """ + 对率回归训练函数。 -def train_logreg(X, y, learning_rate=0.001, iterations=10000, batch_size=64, lambda_reg=0.1): + Args: + - X (numpy array): 特征数据。 + - y (numpy array): 标签数据。 + - other_params (str): 其它参数,可选设置。若需设置其它参数,必须设置其默认值,否则将**无法通过**自动评测,**成绩为零**。 + + Returns: + - numpy array: 训练得到的权重。 + """ m, n = X.shape - weights = np.random.randn(n) * np.sqrt(2. / n) # He初始化 - best_weights = weights.copy() - best_accuracy = 0 - + weights = np.zeros(n) + bias = 0 for _ in range(iterations): - indices = np.random.permutation(m) - X_shuffled = X[indices] - y_shuffled = y[indices] + z = np.dot(X, weights) + bias + h = sigmoid(z) + dw = (1/m) * np.dot(X.T, (h - y)) + db = (1/m) * np.sum(h - y) + weights -= learning_rate * dw + bias -= learning_rate * db + return weights - for j in range(0, m, batch_size): - X_batch = X_shuffled[j:j + batch_size] - y_batch = y_shuffled[j:j + batch_size] - gradient = compute_gradient(X_batch, y_batch, weights, lambda_reg) - weights -= learning_rate * gradient +def predict_logreg(inX, weights): + """ + 对率回归预测函数。 - # 计算训练集准确率 - train_accuracy = accuracy(X, y, weights) - if train_accuracy > best_accuracy: - best_accuracy = train_accuracy - best_weights = weights.copy() + Args: + - inX (numpy array): 输入待分类的样本。 + - weights (numpy array): 训练得到的权重。 - # 动态调整学习率 - if _ % 100 == 0 and train_accuracy > 0.95: # 达到高准确率时减小学习率 - learning_rate *= 0.9 - - return best_weights - -def predict_logreg(X, weights): - z = np.dot(X, weights) + Returns: + - int: 预测的分类标签。 + """ + z = np.dot(inX, weights) h = sigmoid(z) - return np.where(h >= 0.5, 1, 0) + return 1 if h >= 0.5 else 0 def load_data(filepath): - data, labels = [], [] - with open(filepath, 'r') as f: - for line in f: - line = line.strip().split() - if len(line) >= 1 and line[-1].isdigit(): - line_data = [0 if x == '?' else float(x) for x in line[:-1]] - data.append(line_data) - labels.append(int(line[-1])) + """ + 从文件中加载数据,若不自行正确实现,则无法通过评测,**不记录成绩**。 + Args: + - directory (str): 数据文件路径。 + + Returns: + - np.array: 特征数据。 + - np.array: 标签数据。 + """ + data = [] + with open(filepath, 'r') as file: + for line in file: + # 清理无效数据 + cleaned_line = line.strip().replace('?', '0') + values = [float(x) for x in cleaned_line.split()] + # 处理目标变量 + if values[22] in [2, 3]: + values[22] = 0 + new_values = values[:2] + values[3:23] + data.append(new_values) data = np.array(data) - labels = np.array(labels) + X = data[:, :-1] + y = data[:, -1] + return X, y - # 检查特征数量 - num_features = data.shape[1] - - # 特征选择:去掉特征3(索引2)和特征24~28(索引23~26),确保索引有效 - indices_to_delete = [2] # 特征3 - if num_features > 24: # 确保特征数量足够 - indices_to_delete += list(range(24, 27)) # 特征24到27(索引23到26) - - # 删除特征 - data = np.delete(data, indices_to_delete, axis=1) - - # 将标签二分类化,特征23(索引22)取值2和3合并为0,其余为1 - target_variable = np.where((labels == 2) | (labels == 3), 0, 1) - - return data, target_variable - -def accuracy(X, y, weights): - predictions = predict_logreg(X, weights) - return np.mean(predictions == y) - -# 其余代码保持不变 if __name__ == "__main__": - # 加载数据 - X, y = load_data("./data/horse-colic.data") - - # 拆分训练集和验证集 - X_train, X_val, y_train, y_val = train_test_split(X, y, test_size=0.2, random_state=42) - - # 数据归一化 - scaler = MinMaxScaler() - X_train = scaler.fit_transform(X_train) - X_val = scaler.transform(X_val) - - # 训练模型 - final_weights = train_logreg(X_train, y_train, learning_rate=0.01, iterations=5000, batch_size=64, lambda_reg=0.1) - - # 验证模型 - val_accuracy = accuracy(X_val, y_val, final_weights) - print(f"验证集的准确率: {val_accuracy:.4f}") + # 加载训练集 + X_train, y_train = load_data("./data/horse-colic.data") # 加载测试集 X_test, y_test = load_data("./data/horse-colic.test") - X_test = scaler.transform(X_test) - # 测试模型 - final_test_accuracy = accuracy(X_test, y_test, final_weights) - print(f"最终测试集的准确率: {final_test_accuracy:.4f}") \ No newline at end of file + # 训练对率回归模型 + weights = train_logreg(X_train, y_train, learning_rate=0.01, iterations=1000) + + # 测试单个数据 + y_pred = predict_logreg(X_test[11], weights) + print(f"预测结果: {y_pred}, 实际结果: {y_test[11]}") \ No newline at end of file