我正在尝试使用Tensorflow实现一个神经网络。我使用tf.train.GradientDescentOptimizer来最小化熵。然而，它显示了错误ValueError: No variables to optimize

以下是代码

我得到了类似这样的错误

Traceback (most recent call last):  File "NeuralNetwork.py", line 15, in <module>    train_step = tf.train.GradientDescentOptimizer(0.5).minimize(cross_entropy)  File "/usr/local/lib/python3.4/dist-packages/tensorflow/python/training/optimizer.py", line 193, in minimize    grad_loss=grad_loss)  File "/usr/local/lib/python3.4/dist-packages/tensorflow/python/training/optimizer.py", line 244, in compute_gradients    raise ValueError("No variables to optimize")ValueError: No variables to optimize

回答：

您的图中没有任何可优化的变量。

w = tf.zeros([748,10])b = tf.zeros([10])

应更改为

w = tf.Variable(tf.zeros([748,10]))b = tf.Variable(tf.zeros([10]))