Week 2 Exercise 3 Wrong values . Check you formulas for parameters['W1']

Good day. In update_parameters_with_adam I got the result:

W1 =
[[ 1.63980554 -0.62720906 -0.5436752 ]
[-1.088665    0.84990399 -2.28595842]]
W2 =
[[ 0.33513168 -0.26504361  1.47768455]
[-2.04432584 -0.30683853 -0.36853489]
[ 1.14935566 -1.27961162 -0.15697095]]
b1 =
[[ 1.76200086]
[-0.74571222]]
b2 =
[[-0.8940762 ]
[ 0.02681914]
[ 0.56726001]]
---------------------------------------------------------------------------
AssertionError                            Traceback (most recent call last)
<ipython-input-50-99ca62433443> in <module>
7 print(f"b2 = \n{parameters['b2']}")
8

261         assert type(parameters[key]) == np.ndarray, f"Wrong type for parameters['{key}']. Expected np.ndarray"
262         assert parameters[key].shape == parametersi[key].shape, f"Wrong shape for  parameters['{key}']. The update must keep the dimensions of parameters inputs"
--> 263         assert np.allclose(parameters[key][0], expected_parameters[key]), f"Wrong values. Check you formulas for parameters['{key}']"
264         #print(f"{key}: \n {str(parameters[key])}")
265

AssertionError: Wrong values. Check you formulas for parameters['W1']


This result differs by thousandths from the result of the test task. What could be wrong?

Hey @plohih_love,
It would be a little difficult for us to figure out the exact issue from this error stack. Can you please DM me your implementation for the update_parameters_with_adam function?

Cheers,
Elemento

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Please note that a difference in the 3rd decimal place is not a rounding error: itâ€™s a real mistake. Weâ€™re dealing with 64 bit floating point values here, so rounding errors are of the order of 10^{-16}.

The most common problems here have to do with â€śorder of operationsâ€ť. Please check your code and note that the \epsilon value in the formula is in the denominator, but not under the square root, right?

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Thanks everyone. I subtracted Ďµ, not added

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