Course 4 week 1 Assignment 1

All the tests in the graded part have been passed but still the grader gives me 50/100 are there any hidden tests I should check?

The tests in the notebook don’t catch one really important error in the case of conv_forward and pool_forward: they don’t fail if you forget to include the stride in your calculations. In the case of pool_forward, there is a stride = 2 test case and you actually do get values that don’t all match with the shown “expected values”, but you have to look really carefully to notice. But neither of the cases throws an error if you get it wrong. I suggest you carefully check all the values in the pool_forward stride = 2 test case. 50/100 is exactly what you’d get if you got everything right but that one key mistake.

A bug has been outstanding with the course staff for > 1 month at this point about this limitation of the notebook test cases, but no fix is available yet.

Thanks for the help, actually I had accounted for stride but I directly included it as a step in range function range(0,n_H,stride) so when it was 2 my h and w values changed.

Yes, that’s a common mistake. Glad to hear you figured it out! The way to think of it is that the stride happens in the input space, not the output space. The loops are over the output space, so you can’t skip any positions.

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