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<p>我在函数nm\u模型中得到了一个值错误,但是在前向传播函数中的值对于A2是正确的,我不明白为什么会得到这个错误。你知道吗</p>
<pre><code>import numpy as np
for i in range(0, num_iterations):
# Forward propagation. Inputs: "X, parameters". Outputs: "A2, cache".
A2, cache = forward_propagation(X, parameters)
</code></pre>
<p>我这里有个错误
这是我的错误</p>
<pre><code>ValueError Traceback (most recent call last)
<ipython-input-132-7a346e8aefff> in <module>()
1 X_assess, Y_assess = nn_model_test_case()
----> 2 parameters = nn_model(X_assess, Y_assess, 4, num_iterations=10000, print_cost=True)
3 print("W1 = " + str(parameters["W1"]))
4 print("b1 = " + str(parameters["b1"]))
5 print("W2 = " + str(parameters["W2"]))
<ipython-input-131-e266bdc33aa9> in nn_model(X, Y, n_h, num_iterations, print_cost)
33 ### START CODE HERE ### (≈ 4 lines of code)
34 # Forward propagation. Inputs: "X, parameters". Outputs: "A2, cache".
---> 35 A2, cache = forward_propagation(X, parameters)
36
37 # Cost function. Inputs: "A2, Y, parameters". Outputs: "cost".
<ipython-input-129-32057a9db96b> in forward_propagation(X, parameters)
21 # Implement Forward Propagation to calculate A2 (probabilities)
22 ### START CODE HERE ### (≈ 4 lines of code)
---> 23 Z1 = np.dot(W1, X) + b1
24 A1 = np.tanh(Z1)
25 Z2 = np.dot(W2, A1) + b2
ValueError: shapes (4,6) and (2,3) not aligned: 6 (dim 1) != 2 (dim 0)
</code></pre>