[Solved] Updating dictionary in python, during gradient descent

Question

Accessing values in a dictionary requires brackets [], not parentheses () (see this answer. From the code you’ve given us, it looks like grads("db" + str(l+1)) needs to be changed to grads["db" + str(l+1)] to fix your error.

A few notes on style:

The character lowercase ‘l‘ shouldn’t be used as a variable name in order to avoid confusion with capital I or the number 1.
The a = a - b pattern can be replaced with a -= b.
Since str(l+1) is called so frequently, you might consider saving that string as a variable.

Accepted Answer

Accessing values in a dictionary requires brackets [], not parentheses () (see this answer. From the code you’ve given us, it looks like grads("db" + str(l+1)) needs to be changed to grads["db" + str(l+1)] to fix your error.

A few notes on style:

The character lowercase ‘l‘ shouldn’t be used as a variable name in order to avoid confusion with capital I or the number 1.
The a = a - b pattern can be replaced with a -= b.
Since str(l+1) is called so frequently, you might consider saving that string as a variable.