Week 4 - Exercise 5 - Pool backward

Course Q&A Deep Learning Specialization Convolutional Neural Networks
1

Hi,
In exercise 8 (pool backwards), I get an error as shown in the following image:

1
12559×877 136 KB

Would you please give me a hint to find out the issue? I have been tried debugging line by line, however, I couldn’t find out in which line I made a mistake.

Thanks

2

a_prev_slice should be taken for a particular channel, c and not for all channels. See how you’re slicing dA_prev for the hint. Please remove your code references.

3

I revised the a_prev_slice to

                    a_prev_slice = a_prev[vert_start:vert_end, horiz_start:horiz_end,c]

However, I get another error:

1
12270×868 122 KB

4

Please click my name and message your notebook as an attachment.

5

The issue was with the shape of dA_prev it should be of shape A_prev.