Week 2 - Programming Assignment - Exercise 8 - Model Error

I got an error when I test my model when I run the exercise 8.

I checked and checked my code many times, but I didn’t discovery the problem. I need some help, please.


ValueError Traceback (most recent call last)
in
1 from public_tests import *
2
----> 3 model_test(model)

~/work/release/W2A2/public_tests.py in model_test(target)
113 y_test = np.array([0, 1, 0])
114
→ 115 d = target(X, Y, x_test, y_test, num_iterations=50, learning_rate=0.01)
116
117 assert type(d[‘costs’]) == list, f"Wrong type for d[‘costs’]. {type(d[‘costs’])} != list"

in model(X_train, Y_train, X_test, Y_test, num_iterations, learning_rate, print_cost)
37 w, b = initialize_with_zeros(X_train.shape[1])
38
—> 39 params, grads, costs = optimize(w, b, X, Y, num_iterations, learning_rate, print_cost)
40
41 w = params[“w”]

in optimize(w, b, X, Y, num_iterations, learning_rate, print_cost)
35 # grads, cost = …
36 # YOUR CODE STARTS HERE
—> 37 grads, cost = propagate(w, b, X, Y)
38
39 # YOUR CODE ENDS HERE

in propagate(w, b, X, Y)
33 print(“w.T shape:”,w.T.shape)
34 print(“X shape:”,X.shape)
—> 35 A = sigmoid(np.dot(w.T, X) + b)
36 cost = -1./m * np.sum( (Y * np.log(A)) + ((1 - Y) * np.log(1 - A)))
37 # YOUR CODE ENDS HERE

<array_function internals> in dot(*args, **kwargs)

ValueError: shapes (1,7) and (2,3) not aligned: 7 (dim 1) != 2 (dim 0)

I’ve discovered the problem… The call to optimize function was using the X and Y (global variables) instead of X_train and Y_train (parameters).

That’s it!!

1 Like

@John_Jaraceski, good to know that you have solved it on your own!