diff --git a/function.py b/function.py
index 51c9ddc..bcf192b 100644
--- a/function.py
+++ b/function.py
@@ -55,7 +55,7 @@ def train_logreg(X, y, other_params=None):
         z = np.dot(X, weights)
         predictions = sigmoid(z)
         # 计算梯度
-        gradient = np.dot(X.T, (predictions - y)) / m
+        gradient = np.dot(X.T, (predictions.astype(float) - y.astype(float))) / m
         # 更新权重
         weights -= learning_rate * gradient