# C1 W3 Excercise 2 AssertionError

Hello, I’m getting this error: AssertionError: Wrong output. Expected: 0.4529660647 got: 2.7396222491003064. Did you inizialized z_wb = b?

In my code I have z_wb = 0

I then changed to z_wb = b and got the following error: AssertionError: Wrong output. Expected: 0.4529660647 got: 4.231748181538849. Did you inizialized z_wb = b?

Hi @Manuel_Trujillo, Welcome back to the community!!

Please refer to the formula provided in the lab notebook to compute z_wb. The formula for computing z_wb is a combination of the parameters w and b, as well as the input x, rather than simply assigning b to it.

Regards,
Mujassim

Thanks Mujassim,
My comment above was for the initialization so I used z_wb=0
then I used the following formula
{moderator edit: code removed}

But still I’m getting this error: AssertionError: Wrong output. Expected: 0.4529660647 got: 2.7396222491003064. Did you inizialized z_wb = b?

Not sure because of this error, I’m getting an error in excercise 3:

My test result were:
dj_db at test w and b: [-0.02390816 -0.01790596]
dj_dw at test w and b: [-2.390815988969881, -1.7905962579026553]

vs expected:
Expected Output:

dj_db at test w and b (non-zeros) -0.5999999999991071
dj_dw at test w and b (non-zeros): [-44.8313536178737957, -44.37384124953978]

ValueError: The truth value of an array with more than one element is ambiguous. Use a.any() or a.all()

Please check if you are adding the bias term ‘b’ to ‘z_wb’ outside the for loop of this computation. I think you may be simply assigning ‘b’ rather than adding it.

Please send me a screenshot of your implementation of excercise 3 via direct message.

After reviewing your code, there are a couple of corrections that need to be made in your implementation. Please make the modifications that I have provided via inbox and let me know if you have any queries.

Regards,
Mujassim

that was my problem. thanks!