C2_W3_Assignment error forward_propagation Z1 give me error

Course Q&A Math for Machine Learning Calculus for Machine Learning and Data Science
1

Retrieve each parameter from the dictionary “parameters”.

### START CODE HERE ### (~ 4 lines of code)
W1 = 'W1'
b1 = 'b1'
W2 = 'W2'
b2 = 'b2'
### END CODE HERE ###

# Implement forward propagation to calculate A2.
### START CODE HERE ### (~ 4 lines of code)
Z1 = np.matmul(W1, X) + b1
A1 = sigmoid(Z1)
Z2 = np.matmul(W2, X) + b2
A2 = sigmoid(Z2)
### END CODE HERE ###

assert(A2.shape == (n_y, X.shape[1]))

cache = {"Z1": Z1,
         "A1": A1,
         "Z2": Z2,
         "A2": A2}

return A2, cache

Input operand 0 does not have enough dimensions (has 0, gufunc core with signature (n?,k),(k,m?)->(n?,m?) requires 1)

2

Your first block of code only assigns some text strings to the W1, W2, b1, and b2 variables.
That’s not correct.

In your second block of code, you created an A1 variable, but you didn’t use it after that.

Please don’t post your code on the forum, that’s not allowed by the Code of Conduct.