Function sigmoid

NeuralNetwok/NeuralNetwork.py:179–183

(z)

# S型函数    
def sigmoid(z):
    h = np.zeros((len(z),1))    # 初始化，与z的长度一致
    
    h = 1.0/(1.0+np.exp(-z))
    return h

# S型函数导数
def sigmoidGradient(z):