使用python写一段RBF神经网络代码
时间: 2023-05-19 14:02:14 浏览: 354
以下是使用Python编写的RBF神经网络代码:
```python
import numpy as np
class RBF:
def __init__(self, k, lr=0.1, epochs=100):
self.k = k
self.lr = lr
self.epochs = epochs
self.centers = None
self.weights = None
def fit(self, X, y):
# 初始化中心点
self.centers = X[np.random.choice(X.shape[0], self.k, replace=False)]
# 计算每个样本到中心点的距离
distances = np.zeros((X.shape[0], self.k))
for i in range(X.shape[0]):
for j in range(self.k):
distances[i][j] = np.linalg.norm(X[i] - self.centers[j])
# 计算每个样本的输出
phi = np.exp(-distances ** 2)
# 使用最小二乘法计算权重
self.weights = np.linalg.inv(phi.T @ phi) @ phi.T @ y
def predict(self, X):
distances = np.zeros((X.shape[0], self.k))
for i in range(X.shape[0]):
for j in range(self.k):
distances[i][j] = np.linalg.norm(X[i] - self.centers[j])
phi = np.exp(-distances ** 2)
return phi @ self.weights
```
这是一个简单的RBF神经网络实现,其中k是中心点的数量,lr是学习率,epochs是训练轮数。fit方法用于训练模型,predict方法用于预测。
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