Week 3_Exercise 7 : gettting error in output from "update_parameter" functions

My guess is that the problem is that you are using the “in place” style operators for your update. That means:

W -= <... update formula ...>

As opposed to:

W = W - <... update formula ...>

The in place form only works if you first break the connection to the global variables that are the test inputs. Here’s a thread which goes into the details of why this is required.